EPA/625/R-06/012 I August 2007 I www.epa.gov/ord
United States
Environmental Protection
                   Risk Communication in Action
Office of Research and Development
National Risk Management Research Laboratory

                                                                 August 2007
The             of

Ivy Lin, M.S., ASPH/EPA Fellow and Dan D. Petersen, Ph.D., DABT, USEPA
           National Risk Management Research Laboratory
               Office of Research and Development
           United States Environmental Protection Agency
                      Cincinnati, OH 45268


This document has been reviewed in accordance with the USEPA's peer and administrative review policies
and approved for publication. Mention of trade names or commercial products does not constitute endorse-
ment or recommendation for use. Contents of the message maps in this report are representative in nature and
may not be appropriate guidance for actual message maps.


The U.S. Environmental Protection Agency (EPA) is charged by Congress with protecting the Nation's land,
air, and water resources. Under a mandate of national environmental laws, the Agency strives to formulate
and implement actions leading to a compatible balance between human activities and the ability of natural
systems to support and nurture life. To meet this mandate, EPA's research program is providing data and tech-
nical support for solving environmental problems today and building a science knowledge base necessary to
manage our ecological resources wisely, understand how pollutants affect our health, and prevent or reduce
environmental risks in the future.

The National Risk Management Research Laboratory (NRMRL) is the Agency's center for investigation of
technological and management approaches for preventing and reducing risks from pollution that threaten
human health and the environment. The focus of the Laboratory's research program is on methods and their
cost-effectiveness for prevention and control of pollution to air, land, water, and subsurface resources; protec-
tion of water quality in public water systems; remediation of contaminated sites, sediments and ground water;
prevention and control of indoor air pollution; and restoration of ecosystems. NRMRL collaborates with
both, public and private sector partners to foster technologies that reduce the cost of compliance and to an-
ticipate emerging problems. NRMRL's research provides solutions to environmental problems by: developing
and promoting technologies that protect and improve the environment; advancing scientific and engineering
information to support regulatory and policy decisions; and providing the technical support and information
transfer to ensure implementation of environmental regulations and strategies at the national, state, and com-
munity levels.

This publication has been produced as part of the Laboratory's strategic long-term research plan. It is pub-
lished and made available by EPA's Office of Research and Development to assist the user community and to
link researchers with their clients.
                                                Sally Gutierrez, Director
                                                National Risk Management Research Laboratory


Section 1.0 introduces the topics of risk communication and message mapping.

Section 2.0 provides a background on risk communication. Since a message map is a tool used in risk com-
munication, this chapter will discuss the history of risk communication and outline some general principles
of effective risk communication.

Section 3.0 provides information for preparing risk communication messages. Risk perception, risk com-
munication theories and guidelines will be discussed. The role of the media in risk communication will also
be discussed.

Section 4.0 discusses the structure of a message map, and includes a blank message map template as well as
an example of a working message map.

Section 5.0 will provide step-by-step directions about how to create a message map.

Section 6.0 provides examples of how to create a message map in the event of a public health crisis. Examples
chosen are: the West Nile virus epidemic of 2002 in the United States,  the anthrax  scare of 2001 and the
Cryptosporidiosis drinking water outbreak in Milwaukee,  Wisconsin, 1993.

Section 7.0 is a short conclusion.

Section 8.0 is a glossary of important terms.

Section 9.0 is a list of the most frequently asked questions during a crisis.

Section 10.0 is a template for risk communication.

Section 11.0 is a list of references that were cited throughout the paper.



Foreword	iii

How to Use this Workbook	iv

Table of Contents	v

1.0    Introduction [[[ 1
       1.1     What Is a Message Map?	2
       1.2     What Are the Benefits of Using a Message Map[[[ 2

2.0    Background of Risk Communication[[[ 3
       2.1     Introduction to Risk Communication	3
       2.2     Goals of Risk Communication	3
       2.3     History of Risk Communication	4
       2.4     Cardinal Rules of Risk Communication	4

3.0    Risk Perception and the Preparation of Messages	7
       3.1     Risk  Perception[[[ 7
       3.2     Preparing Messages in Advance	9
       3.3     Risk  Communication Theories[[[ 9
       3.4     Other Guidelines for Risk Communication[[[ 11
       3.5     Risk  Communication to the Media and General Public[[[ 12

4.0    Message Mapping - Design and Structure	15
       4.1     Purpose and Structure of a Message Map	15
       4.2     The Overarching Message Map	16

5.0    Creating a Message Map	17


                                               1.   Introduction
In 1976, a 19-year old U.S. Army private named David Lewis
came down with flu-like symptoms, and died within 24 hours.
Two weeks after the private's death, health officials disclosed
to the American public that something called "swine flu" had
killed Lewis and hospitalized four of his fellow soldiers at the
Army base in Burlington County, New Jersey. Healthcare of-
ficials feared a repeat of the 1918 flu epidemic, which killed 20
million people around the world. The Centers for Disease Con-
trol and Prevention (CDC)'s recommendation was to vaccinate
all Americans. The National  Influenza Immunization Program
(NIIP) officially started in October of 1976. The number of vac-
cinations given each week increased rapidly from less than one
million in early October to more than four million in the later
weeks of the month, and reached a peak of more than  six mil-
lion doses a week by the middle of November 1976.' Overall 40
million people were vaccinated, although it was later discovered
that the vaccines were technically flawed and contained only
one of the antigens necessary for an effective inoculation.

Moreover, on December 16, 1976 the NIIP was suspended fol-
lowing reports from more than ten states of a rare degenerative
disease, Guillain-Barre syndrome (GBS), in vaccinated people.
By January of 1977, more than 500 cases of GBS had been
reported,  with 25 deaths. Based on the weekly numbers of vac-
cinations, a comparison of observed cases with expected cases
showed that the relative risk of acquiring GBS  during the six
weeks after vaccination was  about ten times the endemic  ex-
pectation.2 Meanwhile,  the expected mass epidemic of swine
flu never  occurred. However, the regular seasonal flu did break
out, and the only flu vaccines available were mixed with swine
flu vaccine.3

The swine flu incident illustrates the difficulties of risk com-
munication. The fear of a swine flu epidemic was so great that
a mass inoculation program  was implemented without proper
thought and planning. In this case,  the vaccine caused more
harm than good. Currently, there is much concern in the news
about the avian flu, which to date has killed 70 people in Asian
countries.4 But how can organizations prepare for a threat that
is so unpredictable? Communicating risk is a task with unique
difficulties. Law enforcement officials, public health officials,
and government agencies all face the same challenge: in a high-
stress,  high-concern, or emotionally charged situation;  how
does the organization quantify and convey risk in an appropri-
ate, effective and factual manner? What are the proper actions
to recommend (or discourage)? How will the public react? Will
the message change behavior?

hi spite of the challenges, risk communicators have many re-
sources that can help them create informative, balanced, and
well-considered risk messages. Risk Communication is a fairly
new science developed mainly by Vincent Covello and Peter
Sandman. This workbook, Risk Communication in Action: The
Tools of Message Mapping will describe one robust and effec-
tive tool of risk communication, message mapping.
Figure 1-1. The swine flu incident was an example of a risk communi-
cation disaster. Massive stockpiles of swine flu vaccine were prepared
and administered for an epidemic that never became widespread. The
vaccine itself, however, did cause 500 cases of Guillain-Barre syndrome
and 25 deaths.

1.1     What Is a Message Map?

A message map is a  detailed description of hierarchically or-
ganized answers to anticipated questions and concerns from
stakeholders (e.g., the public, the media,  and special interest
groups) in the event of a disaster, crisis, or alarming situation. A
well-constructed message map should bring focus and clarity to
a potentially high-stress, high-concern, or emotionally charged

The three key goals of a message map are:
  •  to educate and inform the public (stakeholders)
  •  to build and maintain trust and credibility between the gen-
    eral public and decision makers during a crisis
  •  to create informed dialogue and decision making among
    the public and figures of authority.

A message map is a template, containing three tiers of informa-
tion. The first tier identifies the audience for the message map
(called the stakeholder) as well as the questions or concerns
that the message map is intended to address. The second tier of
the message map contains three key messages pertaining to the
situation. These key messages can serve as themes for a pub-
lic presentation and sound-bites for the mass media. The third
tier of the message map contains supporting information for the
three key messages. The supporting information is blocked in
groups of three under the key messages. Supporting informa-
tion amplifies the key messages and provides additional facts
and details.
1.2    What Are the Benefits of Using a
        Message Map?

A message map is a useful organizational tool by providing
guidance and clarity to both the authorities and the stakeholders
in a high-stress situation. A well-designed message map helps
multiple partners (e.g., the firemen, the police, the health-care
workers and other authorities) speak with one voice, in a clear,
concise manner. It minimizes the chances of speaker's regret
at an inappropriate comment, omission of pertinent following
information, or disinformation that can confuse stakeholders.
The three key messages  and hierarchically organized support-
ing information provide talking points that a speaker can check
off in order of importance.

hi addition to providing guidance during a crisis, message maps
are useful planning tools in anticipation of potential threats and
crises. Organizations can develop these messages and test them
through focus groups and surveys.

A message  map as a  public health tool was developed by risk
communication expert Vincent Covello in the early 1990s and
was first widely adopted  in the aftermath of the anthrax attacks
of the fall of 2001.

                             2.  Background of Risk Communication
2.1     Introduction to Risk Communication

The National Research Council of the United States gave the
following definition of risk communication: "Risk communica-
tion is an  interactive process of exchange of information and
opinions among individuals, groups, and institutions. It often
involves multiple messages about the nature of the risk or ex-
pressing concerns, opinions, or reactions to risk messages or
to the legal and institutional arrangements for risk manage-

Thus, risk communication involves messages about the  nature
of the risk as well as messages that express concerns, opinions,
and/or reactions to risk messages. An ideal risk communication
tool would put a risk in context, make comparisons with other
risks, and encourage a dialogue between the sender and the re-
ceiver of the message.

Complexities are inherent in any risk situation. Although it is
tempting and sometimes advantageous to use basic, unspecific
terms, risk communicators must also explain the complexity of
the situation. There may be 20 appointed experts with many dif-
ferent assessments whereby opinions and risk regulators must
understand multiple conflicting objectives.  For instance, even
though data overwhelmingly prove that smoking is a carcino-
gen, risk communicators must acknowledge the rights  of the
tobacco industry, as well as those of smokers.

There are also degrees of risk. Risk communication expert Peter
Sandman also makes the distinction between hazard and out-
rage; hazard is the experts' assessment of risk and outrage is the
public perception of risk.6 Some situations may have a very low
hazard factor but a great outrage factor,  while other situations
will have very high hazard but very low outrage. One example
is malaria and tuberculosis,  two diseases that are still top kill-
ers in the developing countries and are increasingly resistant to
treatment but still receive little coverage in the press. It is also
possible to have a situation with both great hazard and great
outrage - i.e. the Chernobyl nuclear reactor incident. The swine
flu incident was an example of a situation that aroused great
outrage but had very little actual hazard. Instead, the real hazard
became the treatment of the swine flu, which caused 500 Guil-
lain-Barre cases and 25 deaths.
2.2    Goals of Risk Communication

Risk analysis experts Ralph  Keeney and Detlof von Winter-
feldt, of the Institute of Safety and Systems Management at the
University of Southern California7, conducted extensive discus-
sions with regulatory officials, after which they listed the objec-
tives of risk communication7:

  • To educate the public about risks, risk analysis, and risk
    Risks should be put in perspective. The public should grasp
    the complexity of the problem and also understand the ra-
    tionale of risk assessment and risk management. The public
    should understand that there is no "zero risk" solution. In
    any risk situation, tradeoffs are necessary, and uncertainty
    cannot be avoided.
  • To inform the public about specific risks and actions
    taken to alleviate them
    Risk managers should speak in user-friendly words as op-
    posed to technical jargon. Accessible graphics/visual aids
    are helpful in achieving this goal.
  • To encourage personal risk reduction measures
    This  is perhaps the most important goal. Ideally, risk com-
    munication should also change individual behavior.  If the
    presentation is about the  dangers of carbon monoxide poi-
    soning, one goal would be to persuade some of the audi-
    ence  to indicate that they  plan to install a carbon monoxide
    detector in their homes.
  • To improve  understanding of public values and con-
    To do this, risk communicators must consider the differ-
    ence  (if any) between hazard and outrage about a risk, and
    the factors that influence  risk perception (see Section 3.0).
    This  understanding will  allow the risk communicators to
    address the issue in an appropriate manner.
  • To increase mutual trust and credibility between the au-
    thorities and the public
    For organizations to exude credibility and engender public
    trust, the manner of communicating risk is critical.  Some
    general guidelines: communication must be honest, must
    not evade or exaggerate, and must not second-guess the au-
    dience. This will engender the audience's trust and build up
    your  credibility.

  • To resolve conflicts and controversies
    Many risk problems become a matter of heated debate and
    controversy because they affect people directly, because
    the authorities and decision makers disagree, and because
    of lost trust and credibility. Risk communicators should at-
    tempt to resolve these conflicts. Their tone should be caring
    and empathetic.

2.3    History of Risk Communication

Risk communication is a relatively new science. Vincent Cov-
ello and Peter Sandman have traced the evolution of risk com-
munication from the 1980s to the present. They specify four
distinct stages8:

Stage 1: Ignore the public
This was  the pre-risk  communication stage  prevalent in the
United States until about 1985. The assumption was that there
was no point communicating risk to the general public, as they
would not heed the warnings or understand the risks. It was
thought that the public was largely content to let authorities
shape environmental policy.

Stage 2: Explain the risk data
From the mid-to-late 1980s, the public reasserted its  claim over
environmental policy.  Many organizations attempted to better
explain risk data.  Explaining risk data to the  public is still a
challenging task for many institutions, however. For instance, if
an EPA spokesperson said, "The maximum allowable arsenic in
drinking water is 10 parts per billion," only a small segment of
the population would understand what that actually means, and
how to follow those guidelines. This is exacerbated by the fact
that many times there is no easy remedy for a risk.

Stage 3: Dialogue with the community
For some  risk problems, such as radon, where the hazard is
large but the controversy is minimal, doing a better job explain-
ing risk data is important.  However, when the hazard is not
great  but public outrage is  very high, simply explaining data
does little to ameliorate a tense situation. An  example of this
occurred in the late 1980s. Medical waste began showing up on
the shore of the Atlantic coastline. In New Jersey, the Depart-
ment  of Environmental Protection reported that the  waste was
not dangerous, but this only increased public outrage. In Rhode
Island, the Commissioner of Health agreed with the public that
the waste was an outrage and unacceptable, and promised to use
any means possible to clean the waste up. This in turn diffused
public outrage and also forced the public to consider the costs
of a thorough cleanup.

Stage 4: Involve the public as a cooperating partner
This is a very difficult stage to achieve, mostly because it is
very difficult for individuals and organizations to adopt new
decision-making approaches. There  is also a mindset within
organizations that they are the experts and that the public is in
general not informed enough to be a fully cooperating partner.
2.4    Cardinal Rules of Risk

Before making a message map it is useful to consider Vincent
Covello and Frederick Allen's Seven Cardinal Rules of Risk

Rule 1: Accept and involve the public as a legitimate part-
Demonstrate respect by involving the community early, before
important decisions are made. People and communities have a
right to participate in decisions that affect their lives and liveli-
hoods. The goal of risk communication is not to diffuse public
concern, but to create an informed public. A scientific experi-
ment that tested public support for space exploration policies
showed that public participation during decision-making about
risks can lead to more acceptance of risk policies.10

Another example of a successful public involvement effort was
a public committee that debated and  resolved several highly
controversial water management issues involving a hydroelec-
tric facility in British Columbia. The body of water of concern
was the Alouette River, and the company, BC Hydro, was the
sponsor of the project. The  Alouette Stakeholder Committee
was made up of 17 official members drawn from a wide array of
organizations,  from various interest groups and local  citizens.
The goal of the committee and BC Hydro was to select the best
possible operating plan for the Alouette River. After 15 meet-
ings, the group reached complete consensus on all major issues
it was asked to address. This is an example of how the public
can be a part of a successful decision-making team.11

Rule 2: Listen to the audience
If people feel that they are not being heard, they cannot be ex-
pected to listen. Effective risk communication is a two-way ac-

Rule 3: Be honest, frank, and open
Organizations  should disclose risk information as soon as pos-
sible without minimizing or exaggerating the level of risk, to
create an atmosphere of trust and credibility. They should lean
towards sharing more information, not less.9

Rule  4:  Coordinate and collaborate with other credible
University scientists, physicians,  citizen  advisory  groups,
trusted local officials, and national or local opinion leaders are
among the credible sources available for collaboration.9

Rule 5: Meet the needs of the media
Print and  broadcast media are prime transmitters of informa-
tion on risks. Communication should be accessible to reporters
and should include digestible sound-bites. Sound-bites are brief
statements, often made  by organizations or reporters, intended
to explain information or defend a position in simple, memo-
rable, easily understandable terms. If organizations  don't sim-
plify, the press will simplify the message at the risk of adding

Rule 6: Speak clearly and with compassion                     Rule 7: Plan carefully and evaluate performance
Technical language and jargon are barriers to successful com-     Risk communication will be successful only if carefully planned
munication with the public. Clear, non-technical language and     and evaluated. Organizations should identify important stake-
sensitivity to cultural norms is essential. Personalizing risk data     holders,  pretest messages  to focus groups, and train staff in
along with graphics to clarify the message will enhance public     communication skills.9


                   3.  Risk Perception and the  Preparation of Messages
3.1     Risk Perception

Risk perception is one of the most complex and challenging
aspects of risk communication. Research on risk perception has
shown that misunderstanding of probability, biased media cov-
erage and misleading personal experiences often cause risks to
be misjudged, underestimated or overestimated.12 Strong initial
views are resistant to change. New evidence is considered "reli-
able and informative" only if it is consistent with initial beliefs.
Contrary evidence  tends to be dismissed as unreliable, wrong,
or unrepresentative.13

Risk communicators must make a distinction between objective
risk (actual risk) and subjective risk (perceived risk). Whereas
risk is objective, risk perception by nature is  subjective. It is
imperative for risk communicators to consider the factors that
influence risk perception before creating any message or state-
ment. Researchers  have studied the characteristics of risk that
influence risk  perception/outrage. A comparison of character-
istics of underestimated risks vs. overestimated risks is listed
in Table 3-1. The most important perception factors are listed

Certain risks  invoke more dread than others.  Cancer, for ex-
ample, causes  more dread than heart disease because cancer is
seen as a terrible way to die. When asked to estimate the aver-
age lifetime chance of developing breast cancer, the average
woman in a 2005 survey guessed that the risk was three times
higher than the actual risk.15

People are more afraid of events when they feel a lack of con-
trol. An example: per mile traveled, the risk that one will die in
a car accident is far greater than the chances of dying in a plane
crash, yet fear  of plane crashes is greater than fear of car crash-
es, because in an airplane there is very little sense of control.14

Natural vs. man-made risk
Man-made risks evoke more  fear than natural risks. Nuclear
energy sources are often a  greater cause of concern than the
radiation produced by the sun, even though the sun's radiation
leads to many skin cancer deaths each year. Likewise, a toxic
Superfund site causes more concern than radon, even though
radon exposure kills more Americans each year than all the Su-
perfund sites  combined.6 (For a definition and explanation of
radon, see the glossary.)
Figure 3-1. Natural vs. man-made risks: Radon in homes increases
risk of lung cancer, but since it is a natural threat there is less fear and
Figure 3-2. Natural vs. man-made risks, and unknown risks: A man-
made risk with unknown hazards such as the Superfund site shown
above (Bunker Hill, Washington, at the Couer d'Alene River Basin)
causes more fear and outrage.

Effects on children
If children are exposed to, say, asbestos or lead paint in schools,
this is perceived as a greater danger than when adults are ex-
posed to the same substances.14
Figure 3-3. Since lead paint affects the cognitive development of chil-
dren, there is great public concern about lead.
Scientifically unknown/new risks
Many risks, such as a toxic Superfund site, are unfamiliar, and
therefore produce a lot of alarm. Another example would be the
SARS epidemic of 2003, which caused great alarm, compared
to the  yearly influenza epidemic, even though the flu causes
more deaths each year.14

Wide coverage by media and public health officials will often
create more alarm in the public. An example is the West Nile Vi-
rus, which has received a lot of coverage in the media in recent
years. Meanwhile, air pollution is a risk that many Americans
are exposed to every day. Health effects include an increased
risk  for cancer, respiratory ailments (including asthma), and
developmental and reproductive problems. Yet, the press rarely
reports about the dangers of air pollution, so most laypeople are
not worried about it.16

Possibility of personal impact
People who are close to a risk, and who have a clear knowledge
of the consequences, will have a greater perception of risk.14

Public perception of risk is greater if the lines of communica-
tion  are from sources  that are perceived  to be untrustworthy.
For instance, studies or statistics about the relationship between
smoking and lung cancer from a tobacco company may be mis-
trusted by many.14
Table 3-1. A Summary of Risk Perception Factors14
Underestimate Risk
Not dreaded (i.e. heart disease)
Scientifically well understood
Controllable by the individual
In the hands of a reliable source
Managed in a responsible way
Immediate health effects
Children not as victims
Not memorable
Little media attention
Victims statistical
Risk to future generation
Overestimate Risk
Dreaded (cancer)
Coercive (involuntary)
Scientifically unknown
Controllable by others
Managed by an unreliable source
Managed in an irresponsible way
Delayed health effects
Children as victims
Much media attention
Personal impact
No risk to future generation
For a hypothetical situation, if the risks are primarily in the "overestimate risk" column of Table 3-1, the public will overestimate the risk and overreact
and/or panic. If the risks are primarily in the "underestimate" column, it will be difficult to persuade the public to adopt risk-decreasing behaviors.
The role of the risk communicator is to overcome these risk perception factors so a balanced assessment of risk can be produced.

Cost-benefit ratio
If there is a perceived benefit in a specific choice, the risk as-
sociated with that behavior or choice will seem smaller than
when no such benefit is perceived. In a study of residents living
near a Tacoma, Washington, copper smelter (which emitted ar-
senic), the respondents with more tolerance towards the smelter
believed that its benefits outweighed its dangers.17

A risk that humans  choose to take seems less hazardous than
one imposed by another person. This explains why many people
skydive or bungee jump, but fear a visit to the dentist.14

Memory of risks
A memorable incident makes a risk easier to evoke and imag-
ine, and therefore seem greater.  For  example, the September
11 attacks instantly made "terrorism" a huge fear among the
American public, although actual acts  of terrorism on American
soil are still exceedingly rare.14
                                   Wrote by Nelson
Figure 3-4. A memorable incident such as the September 11,2001 at-
tacks caused terrorism to become a huge fear for the American public,
although terrorist acts remain fairly rare, at least on American soil.
Spread over space and time
Unusual catastrophic events such as nuclear accidents (e.g., the
Chernobyl nuclear accident in 1986) are perceived as riskier
than commonplace events, such as a hurricane or blizzard. This
is perhaps why many people refuse to evacuate during hurri-
canes despite repeated warnings - they think it's "just another
storm." Along the same lines, people often drive in blinding
snowstorms that cause extremely icy roads and practically no

Effects on personal safety and personal property
An event is perceived as risky when it affects basic interests and
values such as shelter, finances and human life. Examples are
hurricanes and earthquakes.14

Risks perceived to have potentially irreversible adverse effects
are less readily accepted and perceived to be greater than risks
posing no permanent, personal threat.14

Ethical or moral nature
Risks perceived to be ethically or morally objectionable (e.g.,
rape, robbery) are less readily accepted and perceived to be
greater than risks perceived not to be ethically objectionable or
morally wrong, such as a skiing accident.14

Delayed effect
People fear hazards that have a  delayed effect (e.g., carcino-
gens) more than hazards with immediate health effects.14

High risk to future generations
Activities  that pose a threat to future generations  (e.g., radia-
tion from a nuclear accident) are judged to be a more risky than
those that threaten the current generations, such as  influenza.14

3.2     Preparing Messages in Advance

Preparing an appropriate,  concise, effective message prior to
an event actually occurring is probably the most crucial part of
risk communication. When preparing messages, it is important
to consider the several risk communication theories that are out-
lined below.

3.3     Risk Communication Theories

Risk Denial
Risk denial is a  common  reaction to a specified risk. Studies
have shown that individuals may  acknowledge the existence of
a risk, yet assume that they personally are  not vulnerable to it
and are more knowledgeable about hazards relative to others.
hi the Tacoma survey, those who lived the closest to the cop-
per smelter tended also to be  employees at the smelter. These
residents were most likely to deny any risk from the smelter's
arsenic emissions, even though they were most vulnerable to
the emissions. When a risk is counterbalanced with a perceived
benefit, very often the risk is  simply denied.17  Stigmatization,
fear, withdrawal, hopelessness and helplessness can also con-
tribute to risk denial.18 In the case of an infectious disease (such
as AIDS), Stigmatization or fear of Stigmatization may be so

great that ignorance is preferable to seeking help. Fear is also a
psychological consideration in a crisis - it is often debilitating
and prevents quick, decisive action. In other  cases people may
feel that the threat is real, but that there is nothing they can do
about it.  Thus they withdraw into hopelessness and helpless-

Very often people will recognize a risk but consider themselves
less personally in danger than other people. A survey that asked
participants about their personal  vulnerability  to eight risks
(contaminants in drinking water, smoking, radon, chemical
residues on food, AIDS, low-level radioactive waste, and high
blood cholesterol) found that respondents recognized potential
harm to others, but rated their own personal vulnerability to the
eight risks as lower.19

Trust Determination Theory
The trust determination theory proposes that when people are
upset they often doubt that others are listening,  caring, empa-
thetic,  competent, and/or committed. Thus the first and most
important goal of preparing a risk communication message is
building trust with the audience or stakeholders.

According to a survey conducted by the Center for Risk Com-
munication, factors that build trust and credibility are: caring
and empathy; competence and expertise; honesty and openness;
and dedication and commitment.20'21 Caring and empathy are the
most important factors in building trust and credibility. Studies
also show that people make their initial judgments about caring
and empathy within the first 30 seconds.22 It is also important to
build trust and credibility by using support from credible third
party sources. According to surveys, health professionals, sci-
entists, educators and advisory groups have high credibility and
promote trust on health, safety, and environmental issues. Me-
dia and activist groups have medium credibility, while industry
and paid consultants have low credibility.

An example of an industry that regained public trust was John-
son &  Johnson Co. during the Tylenol tampering incident  of
1982. The company aggressively removed all Tylenol from re-
tail shelves. The recall cost the company $100 million, but the
public perception was that Johnson & Johnson was concerned
about public health and safety.20

Mental Noise Theory
The  mental noise theory hypothesizes that  when people are
stressed or upset, they have difficulty hearing, understanding,
and remembering  information.22  Providing  messages to the
public  that are brief, concise,  and clear, while still providing
all necessary information is a way to overcome this challenge.
Ways to ameliorate mental noise include:
  • Provide a limited number of  clear messages: 3 key mes-
  • Keep messages brief: 9 seconds or 27 words
  • Repeat messages
  • Use simple language (6-8 grade level)
  • Use visual aids: graphics, slides, charts, diagrams, video,
  • Use personal stories, rather than impersonal  statistics
Negative Dominance Theory
The negative dominance theory hypothesizes that people tend
to focus more on the negative than on the positive in emotion-
ally charged situations.21 Solutions to the negative dominance
theory include:23-24
  • Balancing negative key messages with positive, construc-
    tive or solution-oriented key messages
  • Employing  a  ratio of at least  3:1 positive to  negative
  • Avoiding unnecessary, indefensible, or nonproductive use
    of absolutes and the words "no,"  "not," "never," "nothing,"

Body Language
Body language,  the  language of gestures  and postures, is an
important - and often decisive - factor in risk communication.22
Experts believe that it provides up to 75% of message impact,
is noticed intensely, and overrides verbal communication. There
are some  general rules  for appropriate body language in risk
communication.  The speaker should make  eye contact; not do-
ing so makes the audience feel that you are dishonest, uncon-
cerned, or nervous. Sit up straight; not doing so can convey lack
of interest or concern.  Do not cross arms; this can be seen as
defiant, defensive or uninterested. Frequent hand to face contact
can seem dishonest  or nervous.  Drumming  or tapping hands
or feet conveys nervousness, hostility or impatience. Resting a
hand on the head can give the impression of boredom or fatigue.
A raised voice can send a message of hostility, nervousness or
deceit. In other words, risk communicators should be trained
about proper body language when speaking to stakeholders.
Figure 3-5. Body language can affect viewer perception, irrespective
of the actual words spoken.

Presentation Format
When people lack strong prior opinions or understanding, they
can be easily manipulated by the way risk information is pre-
sented. In one study, participants were  asked to imagine they
had lung cancer and had to choose between two therapies, sur-
gery and radiation. Some subjects were then presented with the
cumulative probabilities for surviving after the treatment. Other
subjects received the same probabilities, except framed in terms
of dying rather than surviving. Framing the statistics in terms of
dying rather than surviving dropped the percentage of subjects
choosing radiation over surgery from 44% to  18%.25 In another
study, a hypothetical situation about the risk  of side effects of
an influenza vaccine  was presented in either  a probability for-
mat (i.e.  5%) or a frequency format (i.e.  1 out of 20). The 42
subjects given the probability format of 5% were more likely to
describe the risk as "uncommon" or "rare," as  opposed to the 43
people given the frequency format (1 out of 20).26

Pitfalls in Risk Communication22
The Association of State and Territorial Health  Officials lists
common pitfalls made by  organizations when communicating
risks. These  include over-reliance on jargon,  losing one's tem-
per, speaking in overly abstract terms, resorting to personal at-
tacks, giving unrealistic promises and guarantees, referring to
financial concerns, blaming other people/organizations, talking
"off the record," using improper risk comparisons, and talking
for too long.

3.4    Other Guidelines for Risk

1.  The  primacy/recency principle.  This principle states that
    the most important messages should occupy the  first and
    last position in a list26, since information  that is mentioned
    first  or last on a list is the most likely to be remembered.
    The primacy/recency effect has been confirmed in various
    psychological  tests. In one experiment, college  students
    viewed lists  of 15 commercials in a laboratory simulation
    and recalled the product brand names.  In an immediate
    test,  the first commercials in the  list were well recalled (a
    primacy effect), as were the last items (a recency effect), in
    comparison with the recall of middle items.27 The primacy/
    recency effect has also been replicated with  recall of non-
    words28  and affective word lists.29 Non-words in this case
    are letters of the  alphabet jumbled together; affective word
    lists  are words that are related in some way.  For instance,
    an affective  word list  would be:  sadness, grief and heart-

2.  Speak  with  compassion,  conviction,  and optimism.
    This guideline is modeled after the behavior and persona
    of Prime Minister Winston Churchill. In a  time  of great
    stress and turmoil, Churchill was an anchor who embod-
    ied Britain's indomitable spirit during World War II. There
    are many quotations which reflect Churchill's compassion,
    conviction, and optimism, such as:

    •   "Success is not final, failure is not fatal: it is the cour-
        age to continue that counts."
        "The pessimist sees difficulty in every opportunity.
        The optimist sees the opportunity in every difficulty."
        "We shall not fail or falter; we shall not weaken or
        tire...Give us the tools and we will finish the job."30
Figure 3-6. British Prime Minister Winston Churchill's oratory style
serves as a model for effective risk communication.
3.  Average Grade Level Minus Four: During stressful situ-
    ations people do not comprehend information at their nor-
    mal grade level. If a person's normal reading level is eighth
    grade,  during a crisis  his  reading/comprehension might
    drop to fourth-grade level. In a study that compared chil-
    dren who attended a school with high aircraft noise (from
    London Heathrow airport) versus schoolchildren who at-
    tended a school with no aircraft noise, the children chroni-
    cally exposed to aircraft noise were associated with high
    levels of stress, as well as poorer reading comprehension
    and sustained attention.31

4.  Stick to three main points. According to information the-
    ory, both short-term memory and attention span are limited
    by the  number of items the mind can consider simultane-
    ously.32 This is one of the oldest rules of risk communica-
    tion - Aristotle wrote about it in Art of Rhetoric. Famous
    examples  of the "Rule of Three" are  Julius Caesar's "I
    came, I saw, I conquered," or the Declaration of Indepen-
    dence's "Life, liberty, and the  pursuit of happiness." Infor-
    mation theory also states that generally, people organize
    their thinking in terms of only three or four items.33

5.   Use visual aids, such as pictures or graphs, analogies, ex-
    amples, and photographs that can enhance audience com-
    prehension. Experiments have shown that effective work-
    ing memory may be increased by presenting material in a
    mixed (auditory and visual) rather than a single mode.33

6.   For every negative statement, include three positive state-
    ments.  This is the 1N=3P rule. This rule is derived from
    the Negative Dominance Theory, which has also been rep-
    licated in psychological studies. In an experiment where
    subjects were asked to rate pleasant and unpleasant noun
    pairs, the unpleasant noun of a pair made a stronger im-
    pression in recall tests than the pleasant noun.34 If forced to
    make a negative statement, here is the template to follow:

        1.   Positive news
        2.   Acknowledge negative
        3.   Positive statement 1
        4.   Positive statement 2
        5.   Positive statement 3
        6.   Follow up

7.   In the event that the  speaker cannot answer a question that
    is asked, follow this template:

            Repeat the question
            Admit to not knowing the answers
            Give the reasons why
            Indicate follow-up with a deadline for getting the
        •   Bridge to a positive statement: "While I don't
            have  that specific information at the moment I
            want to remind everyone ..."
Below is a table that summarizes general rules for risk commu-
nication, taking into account risk perception, risk communica-
tion theories, and common pitfalls of risk communication.

3.5     Risk Communication to the Media
        and General Public

The mass media exerts an influence on people's perception of
risk, so it is important for risk communicators to understand the
media's strengths and limitations as a tool for risk communica-
tion.  Some risk communicators have charged the media with
exaggerating some risks and ignoring others,  and focusing on
rare, headline-grabbing hazards (terrorism, for example) while
ignoring more commonplace risks (heart attacks). However,
evidence suggests that it is not so much media bias that affects
risk perception, but the media's availability and the medium
with which the information is transmitted.  Television  news
may convey greater danger, resulting in increased levels of fear
among audience members than print media conveys. It is one
thing to read about hurricanes, but seeing destroyed homes and
downed trees on television  makes the risk much more vivid.
hi addition, television often conveys information in less depth
than written media.19

However, it is unclear how much impact the media actually has
on an audience's risk perception. Studies indicate that while the
media can  amplify general  societal risk perception, personal
risk perceptions are much harder to change. Personal risk judg-
ment is based more on personal experiences and direct informa-
Table 3-2. General Guidelines for Good Risk Communication
Good Communication
Clearly state and estimate the risk
Ex: "We have a serious and immediate problem requiring attention ..."
Use clear, non-technical language - write in an eighth-grade reading
level if talking to the general public
Use credible sources - government agencies, scientific experts, reliable
news sources (AP, Reuters, etc.)
Listen to the audience - assume that if one communicates in a clear,
appropriate manner, the audience will understand
Remain calm - do not get agitated or defensive
Keep messages brief - main message about 25-30 words (and 10 sec-
Balance a negative statement with 3 positive statements
Place most important messages first and last
Use visual aids and graphics - charts, videos, pictures, graphs
Repeat messages - three times, to make sure the most important points
are remembered
Speak with a serious tone - it will give the impression of taking the
audience seriously
Poor Communication
Exaggerate or minimize the risk
Ex: "No one has anything to worry about"; "It's time to panic"
Use technical language/jargon - for example, filling the speech with
acronyms ("For the RfD, go to EPA's IRIS")
Use non-credible sources - lobbying groups, industries
Ignore the audience's concerns - a "they won't understand anyway"
Get angry - "That's a stupid question ..."
Make messages long-winded - droning on and on with long lists
Use an overload of negative statements, and words like "no," "never,"
Hide most important message in the middle of the speech
Use impersonal statistics - "the chances of one having an exposure of
more than 50 ppb is about 1 in 1 00"
Mention an important message in passing - "Oh, by the way, the hur-
ricane warning is effective immediately ..."
Add humor - can often come off as flippant or be misunderstood as a
lack of concern

There is, however, evidence that the media's focus is related
to public attitudes. Thus, situations with "high outrage" factors
receive greater coverage. A study of seven British newspapers
found that threats with high  definition  (infectious diseases,
rabies, and food poisoning) were disproportionately reported
relative to their frequency of occurrence.36

Another issue between the media and risk communicators is the
fact that few journalists have the scientific background to sort
through and understand the complex and often contradictory
opinions of risk "experts."37 Therefore it  is important for risk
communicators to be well prepared  and well organized before
any interview with a journalist. There are many ways of getting
emergency information to the media: press releases, press con-
ference, satellite media tours, telephone news conference/web
casts, commercial press releases, email list-servs, web  sites,
and video streaming. There are plusses and minuses to  every
method of communication with the  media.18 The method ulti-
mately chosen will be based on the urgency of the situation, the
risk communicator's time constraints, need for consistency, the
media's time constraints, and financial considerations.

As a rule, the media are more interested in the following20:

  •  Human interest stories (as opposed to statistics)
  •  Bad news (as opposed to good news)
  •  Personal perspectives (i.e. "An eyewitness account of...")
  •  Yes or no (safe or unsafe) answers (as opposed to nuanced,
    ambiguous answers)
  •  Front-page headline news stories
  •  Quick, digestible sound-bites

During a press conference or  another form of communica-
tion with the media, it is important to remember some dos and

  •  Present a short, concise, and focused message
  •  Make the most important points immediately
  •  Give action steps in positives, not negatives
  •  Repeat the message
  •  Create action steps in threes
  •  Use personal pronouns for the organization

Don't Use:
  •  Technical jargon
  •  Filler information that is not pertinent to the main mes-
  •  Condescending or judgmental phrases (i.e. "Anyone with a
    bit of sense would realize ...")
  •  Attacks or judgmental language
  •  Promises/guarantees ("Read my lips, no new taxes" is a
    well-known example.)
  •  Speculation; stick to the facts
  •  Discussion of money or financial considerations; these are
    deemed to be less important in a tense situation than hu-
    man and safety issues
  •  Humor, as it gives an impression of flippancy
Also, remember to break up information into more digestible
pieces for the media. Many experts resent doing this, but if they
don't simplify the news for journalists, they will do it them-
selves, and much confusion and misinformation may result.
Table 3-2 lists some of the Do's and Don'ts of communicating
with the media.


Agency Tender Official
Contract Data Requirements List
Code of Federal Regulations
Contract Line Item Number
Contracting Officer
Competitive Sourcing Official
Federal Activities Inventory Reform
Federal Acquisition Regulation
Federal Insurance Contribution Act
Full-time Equivalent
Federal Wage System
General Accounting Office
Government-Furnished Property
General Schedule
Human Resource Advisor
Most Efficient Organization
Office of Management and Budget
Office of Personnel Management
Performance Work Statement
Service Contract Act
Standard Competition Form
Streamlined Competition Form
Source Selection Authority
Source Selection Evaluation Board
United States Code
Voluntary Early Retirement Authority
Voluntary Separation Incentive Pay
Figure 3-7. Filling a speech with acronyms like the ones listed above
often just confuses listeners.


                        4.  Message  Mapping - Design and Structure
4.1     Purpose and Structure of a Message

The principles of risk communication can be applied when cre-
ating a message map. The message map is an organized means
for displaying layers of information. It contains detailed, hier-
archically organized responses to anticipated questions or con-
cerns. It helps organizations meet several risk communication

  •  Identify stakeholders early on in the communication pro-
  •  Anticipate the questions and concerns of the stakeholders
    before they appear.
  •  Organize our thoughts and ideas and prepare messages in
    response to the concerns and questions of the stakehold-
  •  Develop key messages and supporting information in the
    context  of a clear, concise, transparent,  and accessible
  •  Promote an open dialogue about the messages both inside
    and outside the organization.
  •  Provide the spokesperson with a user-friendly guide.
  •  Make sure that the organization has consistent information
    and messages.
  •  Make  sure that the organization speaks with a  single
A message map template is a three-tiered grid containing mul-
tiple boxes (see Figure 4-1 below).

  •  The top tier of the template identifies the audience for the
    message map as well as the question or concern that the
    message map is intended to address.
  •  The second tier of the message map contains three key
    messages that answer the question or concern.
  •  The third tier contains supporting information, which is
    blocked in groups of 3's under each key message. Support-
    ing messages amplify the key messages, and provide ad-
    ditional facts or details. They can take the form of visuals,
    analogies, personal  stories, hotline numbers,  and/or cita-
    tions of credible sources of information.
Question or Concern:
Key Message 1

Supporting Information 1-1

Supporting Information 1-2

Supporting Information 1-3

Key Message 2

Supporting Information 2-1

Supporting Information 2-2

Supporting Information 2-3

Key Message 3

Supporting Information 3-1

Supporting Information 3-2

Supporting Information 3-3

Figure 4-1. Template of a message map.

4.2    The Overarching Message Map

The Overarching Message Map (see Figure 4-2 below) is the
most important message map. If a message map were a news-
paper article, the Overarching Message Map would be the
headline and the first paragraph. It contains and displays the
organization's key messages. At an EPA sponsored workshop
for Water Utilities and Water Security and Message Mapping in
March 2005, an Overarching Message Map38 was described as:
  •  What the speaker/organization most wants people to know
    about the issue or topic
  •  What the speaker/organization would put in the opening
    statement at a presentation or press conference relating to
    the issue and topic.

Suppose the situation is an ongoing influenza epidemic. The
Overarching Message Map would look something like what is
shown on Figure 4-3.
    How  you  can
    Vaccination 1$ not the only way to combat the flu.
 Use these simple lips lo prevent the flu before it happen*.
                  Avoid close contact.
           Avoid close contact with people who are sick.
            When you are sick, keep your distance from
           others to protect them from getting sick too.
                    Clean your hands.
                Washing your hands often will help
                    protect you from germs.

               Stay home when you are sick.
       iftf.f. If possible, stay home from work, school, and
           errands when you arc sick. You will help prevent
                others from catching your illness.

             Cover your mouth and nose.
          Cover your mouth and nose with a tissue when
           coughing or sneezing. It may prevent those
                around you from getting sick.

     Avoid touching your eyes, nose, or mouth.
     ^   Germs art often spread when a person (ouches
        something that is contaminated with germ and then
           touches his or her eyes, nose, or mouth.
                                                      Figure 4-3. A message map can serve as a guideline for a health
                                                      awareness poster like the one above.
Stakeholder: Public, health care workers
Question or Concern: What does the public most need to know about the influenza epidemic?
Key Message 1
Vaccination a top priority for:
Supporting Information 1-1
Supporting Information 1-2
Health care workers
Supporting Information 1-3
Immuno-compromised individuals
Key Message 2
Supporting Information 2-1
Supporting Information 2-2
Congestion (cough, sore throat)
Supporting Information 2-3
Muscle aches and pain
Key Message 3
Highly contagious
Supporting Information 3-1
Avoid direct contact with others
Supporting Information 3-2
Avoid sharing food, drinks
Supporting Information 3-3
Keep bedding (sheets, linens) clean
Figure 4-2. Example of an overarching message map.

                                    5.  Creating a Message Map
A message map can be one of the most useful of risk com-
munication tools. It is important, however, to create well-con-
structed message maps in order to effectively communicate
with the public by clearly explaining the situation, the risks, and
the remedies. Before getting started, remember these important

  • Be prepared. Know the subject and the audience.
  • Prepare your key messages. Remember, limit to three key
    messages and a maximum of three supporting statements
    for each key message.
  • Keep answers short and focused.
  • Speak and act with integrity. Tell the truth.

5.1     The Creation of a Message Map Can
        Be Separated into Eight Steps

Step 1: Identify stakeholders
The first step is to identify stakeholders. Stakeholders include
the public  at large as well as all interested, affected, or influen-
tial parties in a situation. Supposing the risk alert concerned
influenza, stakeholders would include the public at large, health
care workers, public health officials, as well as those most at
risk for influenza (the elderly, for example).

Identifying stakeholders is also a crucial step of the message
mapping process because risk communicators must adjust their
messages to fit the needs and capabilities of an audience. A situ-
ation where the stakeholders are children/laypeople would yield
a very different message map than a message map where the
stakeholders are doctors or health workers.

Step 2: Identify anticipated stakeholder questions and con-
Prepare  a complete list of specific questions and concerns  for
each major group of stakeholders. A list of the Most Commonly
Asked Questions by a Journalist is contained in Section 9.0. The
questions that are generated or anticipated are the first tier of the
message map grid. Questions and concerns typically fall into
three  categories, overarching questions,  informational  ques-
tions, and challenging questions. Overarching  questions are
broad in topic and are developed by the organization to analyze
the general status of a situation. Informational questions ask
about a  specific aspect  of the situation. Challenging questions
are often hostile/tense in tone. Examples are:

Overarching questions: "What do people need to know?"
Informational questions: "What is the budget for your re-
Challenging questions: "Why should we trust what you are
telling us? How many people have to die before you take
more aggressive action? Can you guarantee that people are
safe? What are you not telling us?"
Lists of specific stakeholder questions and concerns can be gen-
erated through34:

  • Focus groups
  • Surveys
  • Media content analysis
  • Reviews of complaint logs, hot line logs, toll free number
    logs, and media logs
  • Focused interviews with subject matter experts
  • Public meeting records, public hearing records, and legisla-
    tive transcripts

Step 3: Identify frequent concerns
Make an analysis of the list of specific concerns, and identify
common groups of underlying general concerns. Case studies
indicate that most high-concern issues are associated with no
more than 15-25 categories of concern. As part of this step, it is
useful to create a matrix or table matching the stakeholders (in
order of priority) with their concerns. Here is a list of common
sets of concerns:39 human health, trust, safety, environment,
information, ethics, economics,  responsibility, legal, process,
pets/livestock, religion,  fairness.

Step 4: Develop key messages
When preparing the messages, it is important to consider the
risk communication theories outlined in Section 3.3 (mental
noise, negative dominance theory, etc.). During  staff brain-
storming sessions, key words should emerge for each message.
Each issue should have no more than three key messages. These
key messages fill in the  second tier of the message map.

Step 5: Develop supporting information
The fifth step of constructing a message map is to develop sup-
porting facts, information, or proofs for each key message. Sup-
pose for a message map about influenza one key message was,
"All high-risk groups must be vaccinated." The supporting mes-
sages in this instance would be directed to the high risk groups:
the elderly, the immuno-compromised, or health care workers.

These supporting messages fill in the third tier of the message
map for this key message.

Step 6: Conduct testing
The sixth step of message mapping is to conduct systematic
pre-testing. The message testing should start by asking experts
on the topic at hand, who were not involved in the original mes-
sage-mapping process, to validate the accuracy of the informa-
tion. Subsequently, the message  map should be tested on fo-
cus groups that are representative of target stakeholders. (For
instance, supposing the message map was about influenza, a
focus group could be elderly citizens planning to get the flu

Step 7: Overarching Message Map39
An Overarching Message Map contains the organization's core
messages. The Overarching Message Map addresses:

  • What people most need to know about the issue or topic
  • What to put in the opening statement at a presentation or
    press conference relating to the issue or topic

One method for assuring that the message of the Overarching
Message Map is delivered to the audience is  bridging. Bridg-
ing is a tool used by risk communicators to connect statements
and responses in a smooth, straightforward manner. During an
influenza epidemic, an example of a bridging statement might
be: "I want to remind you again that the influenza vaccine is
easily available at all local  hospitals and clinics ...."

Step 8: Delivery
The key to successful delivery is anticipation, preparation, and
practice. Once the message map has been pre-tested, it should
be delivered through a trained spokesperson through suitable
media (i.e. a news conference or a recorded reply in emergency
telephone lines, etc.). The stakeholders must feel that their con-
cerns are treated seriously. Audiovisual aids are often very help-
ful in a presentation.
The presentation sequence should follow these guidelines:22

    1. Introduction
    Perceived empathy is a vital factor in establishing trust and
    building credibility,  and it is assessed by your audience in
    the first 9-30 seconds. Include a statement of concern, a
    statement of organizational intent, and a statement of pur-
    pose and plan for the meeting.

    2. Key messages and supporting data
    Stress the three key messages you want the public to have in
    mind after the meeting. Then mention the supporting data,
    which amplifies, clarifies, or bolsters the key messages.

    3. After the presentation
    After the speaker has given all the information contained in
    the message map, he must answer questions from the me-
    dia and stakeholders. The speaker should prepare before-
    hand answers to some common, anticipated questions and
    concerns from the press and stakeholders.

                      6.   Message  Mapping in Action: Three Examples
The  next three sections will  provide examples  of message
maps relating to real-life crises. These message maps provide
a guideline for commonly asked questions during a crisis. In
each case, real-life events provide some context and familiarity.
They include West Nile Virus of 2002, the anthrax bioterrorism
event of 2001, and the 1993 Cryptosporidium drinking water
contamination episode in Milwaukee.

6.1     The West Nile Virus: Crisis Summary
        and Message  Maps

Time and location of crisis:
The  West Nile Virus started to attract much attention in the
United States during the summer of 2002. Thirty-nine states
and the District of Columbia reported a total of 4,156 cases of
human West Nile Virus illness.40

West Nile Virus - a background:
West Nile Virus is indigenous in Africa, Asia, Europe, and Aus-
tralia. West Nile Virus was first isolated in 1937 from the blood
of a  febrile (feverish) female patient in the West  Nile district
of Uganda.41 The virus can cause severe human meningitis and
encephalitis, both of which are characterized by inflammation
of the spinal cord and brain.

The  main route of human infection from West Nile Virus is
through the bite of an infected mosquito belonging to the Culex
genus. Mosquitoes become infected when they feed on infected
birds. The virus eventually gets into the salivary glands of the
mosquito. During later blood meals (when mosquitoes bite), the
virus may be  injected into humans and animals, where it can
multiply and possibly cause illness. Although mosquito bites
are the most common method  of infection, blood  transfusions
and organ donations are also possible methods of infection. The
majority (80%) of West Nile viral infections are asymptomatic
- without any signs of disease.  The most common  (20%) clini-
cal symptom  is uncomplicated West Nile fever, which is not
life-threatening. The virus, however, can cause severe or fatal
neuroinvasive illness.

First indication of event:
The West Nile Virus's first introduction to North America was
in 1999, when an unusual cluster of cases of meningoencepha-
litis was documented in New York City. The initial symptom
was severe muscle weakness. At the same time, an epizootic
disease (i.e. affecting a large number of animals) was causing
the deaths of substantial numbers of birds in the New York City
area. The West Nile Virus was isolated from tissue specimens
obtained  from American crows in Westchester  County and a
Chilean flamingo in a nearby zoo. West Nile Virus was deter-
mined to be  the common cause of the encephalitis outbreaks
among both birds and humans.42

The ArboNET surveillance system was established by the Cen-
ters for Disease Control in 2000 to monitor the spread of West
Nile Virus in the United  States. In  2002, 4,156 human West
Nile virus illnesses were  reported to ArboNET from 39 states
and the District of Columbia. Of the 4,156 reported cases, 71%
were neuroinvasive, 28% were uncomplicated West Nile fever,
1% was unspecified. There were 284 fatalities (6.8%) out of the
4,156 reported cases.
Figure 6-1. An electron micrograph of the West Nile Virus, which can
infect mosquitoes, birds, humans, and other mammals.

Clinical features of West Nile Virus:
The symptoms of West Nile Virus closely resemble the symp-
toms of the St. Louis Virus, a flavivirus also transmitted by
mosquitoes of the Culex genus, and other worldwide outbreaks
of arboviral encephalitis.43 Arboviruses are any of a large group
of viruses transmitted by arthropods, such as mosquitoes and
ticks, that include the causative agents of encephalitis, yellow
fever, and dengue. A flavivirus  is one form of arbovirus. The
majority (80%) of West Nile viral infections are asymptomatic
- without any signs of disease.  For those infected who do get
sick, the incubation period is approximately 2-14 days.44 For
those who do show clinical symptoms of infection, the most
common (20%) clinical  symptom is uncomplicated West Nile
fever. Uncomplicated West Nile fever typically begins with an
onset of fever, headache, and myalgia (muscle pain) often ac-
companied by gastrointestinal symptoms. The acute illness usu-
ally lasts less than one week, but prolonged fatigue is common.
It is not life-threatening.

About  one out of 150 people that are infected will develop
neuroinvasive illnesses such as encephalitis  (inflammation of
the brain), meningoencephalitis  (inflammation of the brain and
surrounding membranes), and meningitis (inflammation of the
membranes  surrounding the brain). Encephalitis, meningitis,
and meningoencephalitis, can be fatal, especially in older vic-
tims. Most West Nile case  fatalities are due to encephalitis and
What can the public do to avoid West Nile Virus?
Since the primary  method of West Nile Virus  infection is
through mosquito bites, preventing bites is the best way to avoid
WNV There are simple steps the public can take to avoid being
bitten by mosquitoes:

  • Remove  standing water, including old  tires that serve as
    breeding grounds for mosquitoes.
  • Wear long-sleeved shirts and pants and avoid going  out
    during "bite hours" - dusk till dawn.
  • Use bug repellant that contains DEBT

What is being done to prevent future outbreaks?
The methods of prevention of future West Nile Virus outbreaks
fall into three categories:  surveillance, source reduction, and
chemical control.45'46 Surveillance identifies mosquito species,
location, ecologic locations, seasons, and breeding cycles. Ar-
boNET is a nation-wide electronic database for states sharing
information about WNV Source reduction attempts to reduce
mosquito opportunities by altering the habitat to make condi-
tions unfavorable for larval breeding. In  the case of West Nile
Virus the Culex pipiens mosquitoes tend to breed in standing
water. Chemical control involves the use of pesticides to reduce
mosquito populations.
                                              WEST NILE VIRUS
                                           TRANSMISSION CYCLE
                                   Some species of mosquitoes carry &
                                   amplify the virus. They Ir.msmil ihe virus
                                   when they bile to gel a protein bUxid me»l
                                   before laying eggs
             M0tl »p«tn are
                                   Infected mosquitoes bite birds tc. infer I
                                   them. Some infected birds lr.m-.mil llu-
                                   virus to other mosquitoes when Hlten
                                   4g4in. Birds of some species get ill;
                                   others do not show disease symptoms,
                                   although infected. Infected migrating
                                   birds carry the virus to new places.
           MAMMALS ARE
               DEAD END
            IlK Irvrl at vimnu
               in mAmnult it
            K«*TK rj|l> Sow low ID
           transmit Ito infection
            Figure 6-2. The West Nile transmission cycle, in which infected mosquitoes infect birds, humans, and other animals.

6,1.1   Message Maps about the West Nile Virus
Message Map 1: Overarching Message Map
This is an overarching message map, and it contains information the public most needs to know about the West Nile Virus: how one
gets infected with the virus, the health effects of West Nile Virus, and the simple methods one can employ to avoid infection.
Stakeholder. Public/Media
Question or Concern: What does the public most need to know?
Key Message 1
West Nile Virus transmitted by infected mos-
Supporting Information 1-1
Mosquitoes become infected from biting in-
fected birds
Supporting Information 1-2
Blood-blood transmission also possible
Supporting Information 1-3
Human-to-human contact not believed to be a
mode of transmission
Key Message 2
Health effects of West Nile Virus are:
Supporting Information 2-1
80% of all infections are asymptomatic
Supporting Information 2-2
Uncomplicated West Nile Virus fever: 20%
Supporting Information 2-3
Encephalitis, Meningitis, Meningoencephalitis:
1 out of 150 cases, usually in elderly (<1 %)
Key Message 3
There are simple steps people can take to
avoid infection
Supporting Information 3-1
Spray with DEBT
Supporting Information 3-2
Wear long-sleeved clothing
Supporting Information 3-3
Remove any standing water
Message Map 2: What happened? What should the public know?
This message map answers the "who, what, when, where, why?" questions. In this case, the message map documents the epidemic
in the United States during the summer of 2002, and how the West Nile Virus became a health risk via mosquitoes. The last key
messages are about avoiding infection.
Stakeholder: Public/Media
Question or Concern: What happened (Who, what, when, where, why?) What should the public know?
Key Message 1
A West Nile Virus epidemic in the U.S. in the
summer of 2002
Supporting Information 1-1
4,1 56 cases of West Nile Virus in 39 states and
the District of Columbia
Supporting Information 1-2
Of the cases, 71 % neuroinvasive, 28% uncom-
plicated, 1 % unspecified, 284 (< 7%) fatal
Supporting Information 1-3
First U.S. cases discovered in New York City,
Key Message 2
West Nile Virus transmitted by infected mos-
Supporting Information 2-1
Mosquitoes become infected from biting in-
fected birds
Supporting Information 2-2
A flavivirus - a virus transmitted by mosqui-
Supporting Information 2-3
Virus originally from Eastern hemisphere
Key Message 3
There are simple steps people can take to
avoid infection
Supporting Information 3-1
Spray with DEET
Supporting Information 3-2
Wear long-sleeved clothing
Supporting Information 3-3
Avoid exposure during "biting hours" - dusk to

Message Map 3: How did you find out about the West Nile virus?
This message map explains the discovery of West Nile Virus in the United States, and how the first human cases were diagnosed.
Stakeholder: Public/Media
Question or Concern; How did you find out about the West Nile Virus?
Key Message 1
First cases of meningoencephalitis in NYC,
Supporting Information 1-1
719 patients with reports of meningitis and en-
Supporting Information 1-2
62 of these 71 9 patients were confirmed West
Nile Virus cases
Supporting Information 1-3
Illness resembled St. Louis encephalitis, as
well as other outbreaks of encephalitis in Eu-
rope and Israel
Key Message 2
Deaths of birds occurring in NYC area
Supporting Information 2-1
West Nile infection among birds more geo-
graphically widespread than among humans
Supporting Information 2-2
Flavivirus isolated from birds
Supporting Information 2-3
Virus determined to be the common cause of
the bird/human illnesses
Key Message 3
Virus determined to be West Nile Virus
Supporting Information 3-1
Mosquito with WNV bite birds
Supporting Information 3-2
Mosquitoes with WNV also bite humans
Supporting Information 3-3
Although most cases of WNV are asymptom-
atic, some cases can be fatal; prevention from
mosquito bites is crucial
Message Map 4: What are the health effects associated with West Nile Virus?
There are three major health effects of West Nile Virus. The majority (80%) experience no health effects. About 20% have uncom-
plicated West Nile fever. One in 150 cases will develop potentially fatal neuroinvasive illnesses such as meningitis, encephalitis, and
Stakeholder: Public/Media
Question or Concern: What are the health effects associated with West Nile Virus?
Key Message 1
Older people are more at risk for serious ill-
Supporting Information 1-1
Incubation period is 2-14 days
Supporting Information 1-2
Eventual clinical symptom is a neuroinvasive
Supporting Information 1-3
About 20% or one-fifth of people over 70 died.
Deaths occurred in people averaging 77 years
Key Message 2
Mosf infections are not life-threatening
Supporting Information 2-1
80% of all infections are asymptomatic
Supporting Information 2-2
20% have mild illness, called West Nile Fever,
often accompanied by gastrointestinal symp-
Supporting Information 2-3
Acute illness typically lasts one week, but pa-
tients report prolonged fatigue
Key Message 3
About 1 in 150 infections develop meningitis,
encephalitis, or meningoencephalitis
Supporting Information 3-1
Muscle weakness often the first symptom
Supporting Information 3-2
Encephalitis and meningoencephalitis most
Supporting Information 3-3
In 2002 epidemic, of the 2,942 neuroinvasive
illnesses, 276 (9%) were fatal

Message Map 5: What can people do to prevent West Nile Virus?
The simple steps people can take to prevent West Nile Virus fall under three categories: remove standing water, wear protective
clothing, and use insect repellent.
Stakeholder; Public/Media
Question or Concern: What can people do to prevent West Nile Virus?
Key Message 1
Remove standing water
Supporting Information 1-1
Remove old tires which collect water and serve
as breeding grounds for mosquitoes
Supporting Information 1-2
Empty or clean flower pots and bird baths
Supporting Information 1-3
Empty and clean cat/dog water bowls daily
Key Message 2
Wear protective clothing
Supporting Information 2-1
Wear long sleeved shirts
Supporting Information 2-2
Wear long pants
Supporting Information 2-3
Especially at dawn and dusk
Key Message 3
Use insect repellent
Supporting Information 3-1
Repellents containing DEET are recommend-
Supporting Information 3-2
Use 23% DEET
Supporting Information 3-3
Do not use repellents that do not contain
Message Map 6: What is being done to prevent this in the future?
The large-scale prevention measures against West Nile Virus fall into three categories: surveillance (monitoring outbreaks), source
reduction (reduce breeding grounds), and chemical control (pesticides).
Stakeholder; Public/Media
Question or Concern: What is being done to prevent this in the future?
Key Message 1
Surveillance - monitor possible outbreaks
Supporting Information 1-1
Larval mosquito surveillance
Supporting Information 1-2
Adult mosquito surveillance
Supporting Information 1-3
Virus surveillance
Key Message 2
Source reduction - reduce opportunity
Supporting Information 2-1
Reduce breeding ground
Supporting Information 2-2
Water management
Supporting Information 2-3
Personal prevention measures
Key Message 3
Chemical control - use pesticides
Supporting Information 3-1
Larvaciding - killing larvae
Supporting Information 3-2
Adulticiding - killing adult mosquitoes
Supporting Information 3-3
These efforts are usually far from complete

Message Map 7: How did this happen?
This message map outlines the history of West Nile Virus, from the very first isolated patient (in 1937) to its introduction into the
United States.
Stakeholder: Public/Media
Question or Concern: How did this happen?
Key Message 1
Virus indigenous in Europe, Africa, Asia, and
Supporting Information 1-1
West Nile Virus first isolated in 1937
Supporting Information 1-2
Epidemics in Israel and South Africa
Supporting Information 1-3

Key Message 2
Detected in NYC in 1999
Supporting Information 2-1
Also detected in birds in North America
Supporting Information 2-2
Extended its range to much of the East Coast
of the United States
Supporting Information 2-3
Horses also infected
Key Message 3
Mode of introduction into United States un-
Supporting Information 3-1
Mosquito-borne transmission
Supporting Information 3-2
Blood-blood transmission also possible
Supporting Information 3-3
Human-to-human contact not believed to be a
mode of transmission
6.2    Bioterrorism (Anthrax): Crisis
        Summary and Message Maps

Time and location of event:
The anthrax scare occurred during the fall of 2001 in the United
States. Anthrax was deliberately spread through the postal sys-
tem by sending letters with powder containing anthrax. These
letters were all sent from Trenton, NJ, and mailed to Florida,
Washington D.C., and New York City. The letters seemed to
target government or media figures - one letter was sent to an-
chorman Tom Brokaw's office, another to Senator Tom Dasch-
le's office. This caused 22 cases of anthrax infection.47 To date
the culprits behind the anthrax attacks have not been found.

                CAN NOT  STOP  us.

           we  HAW  THIS
                 Dig   Now.

           ^*t  Vou  APA

           Dear*  TO
            AUAH   15
Figure 6-3. A photo of the letter sent to Senator Tom Daschle's office
that contained anthrax spores.
Anthrax - a background:
Anthrax is an acute infectious disease caused by the  spore-
forming bacterium Bacillus anthracis. It has a long reputation
as deadly bacteria - the fifth and sixth plagues of the Exodus
might have been outbreaks of anthrax  in cattle and humans,
respectively.46 Anthrax most commonly occurs in wild and do-
mestic animals, but it can also occur in humans when they are
exposed to infected animals or when anthrax spores are used as
a bioterrorism weapon. In the mid-1800s, it became known as
the wool sorters' disease in England and the rag pickers' disease
in Germany and Austria because of the  frequency of infection
in mill workers exposed to imported, contaminated animal fi-
bers. In the early 1900s, human cases of inhalational anthrax
also occurred in the United States  in conjunction with the tex-
tile and tanning industries.49 Research on anthrax as a biological
weapon began more than 80 years ago.50

First indicator of anthrax bioterrorism:
In September 2001, Bacillus anthracis spores were sent to sev-
eral locations via the U.S. Postal Service. It wasn't until October
2, 2001, that a physician recognized a possible case of inhala-
tion anthrax in a patient hospitalized in Palm Beach County,
Florida. The diagnosis of B. anthracis  was confirmed by the
Florida Department of Health and the CDC on October 4. Ev-
idence of B. anthracis was found at American Media Inc. in
Boca Raton, Florida, where this first victim worked as a photo
editor. This was the first known case of anthrax in the United
States.52 Eventually there were 22 confirmed or suspected cases
of anthrax infection, all believed to be from contaminated letters
delivered via the postal system. Eleven patients were inhalation
cases, of these, five  died; the other 11 were non-fatal cutaneous
(under the  skin) cases.52

Clinical features of anthrax:
Anthrax infection can occur in three forms: cutaneous, inhala-
tion,  or gastrointestinal. Most (95%)  cases occur cutaneously

when the bacterium enters the skin. This can occur during han-
dling of contaminated wool or leather, or touching of infected
animals. The first symptom is an infected area of the skin: a
raised itchy bump that resembles a bite, but within 1-2 days
develops into a vesicle and then a painless ulcer. About 20%
of untreated cases will result in death, so it is important to seek
antimicrobial therapy quickly after infection.
Figure 6-4. A microscopic photograph of Bacillum anthracis that has
had a long historical reputation as a deadly bacteria.
Inhalation anthrax is a biphasic illness - there are two distinct
phases. In the first phase, the symptoms are not alarming; they
may resemble a cold. After several days  the symptoms may
progress to severe breathing problems and  shock. Unless treat-
ed, inhalational anthrax  can be fatal. The incubation period is
1-6 days.

Gastrointestinal infection is the rarest form of anthrax infection.
The intestinal disease form of anthrax may follow the consump-
tion of contaminated meat and is characterized by an acute in-
flammation of the intestinal tract. Initial signs of nausea, loss of
appetite, vomiting and fever are followed  by abdominal pain,
vomiting of blood, and  severe diarrhea. Intestinal anthrax re-
sults in death in 25% to 60% of cases.

The most common treatment  for anthrax is antibiotics, usu-
ally ciprofloxacin,  doxycycline, and penicillin. The regimen is
usually a grueling  60 days of antibiotic treatment.  A vaccine is
available, but it is usually given only to military personnel and
"high risk" people such  as those who work in laboratories that
handle anthrax. Anthrax has little potential for person-to-person

What can the public do to prevent anthrax exposure?
  • Do not open any suspicious mail
  • Keep mail away from the face
  • Do not sniff/blow into mail
  • Wash hands after opening mail
  • Discard envelopes after opening mail
  • Persons who  think they might have been exposed should
    contact a health provider immediately
What has been done to prevent future attacks?
The CDC has developed plans and procedures to respond to an
attack using anthrax. The plans fall into three categories: sur-
veillance, education, and equipping.

The CDC has trained emergency response teams to help state
and local governments control infection, gather samples, and
perform  laboratory tests  in the national Laboratory Response
Network (LRN).  The LRN  is a collaborative system linking
state and local public health laboratories with advanced ca-
pacity  laboratories—including  clinical,  military,  veterinary,
agricultural, water, and  food-testing laboratories—to rapidly
identify threat agents, including anthrax. The CDC is working
closely with health departments, veterinarians, and laboratories
to watch for suspected cases of anthrax. It has developed a na-
tional electronic database to track potential cases.

The CDC has educated health-care providers, the media, and
the general public about what to do in the event of an attack.

To ensure that there are  enough laboratories for quick testing
of suspected anthrax cases, the CDC is working with hospitals,
laboratories, emergency response teams, and health-care pro-
viders to make sure they  have the supplies they need (antibiot-
ics, assays) in case of an attack.

In 2004, President Bush  signed into law the Project Bioshield
Act, which establishes a permanent funding  source  through
which the  federal government can buy medical countermea-
sures (vaccines, diagnostic tests, human and animal drugs) from
private companies. Project BioShield gives  the FDA authority
to make promising drugs, vaccines, or diagnostic tests quickly
available in emergencies.54

The question might arise: if there is a vaccine for anthrax, why
not distribute it widely, in the same way as yearly flu vaccines?
The reason is efficiency.  Since anthrax is still a rare infection,
the percentage of people that need to be pre-vaccinated would
be extremely high (63-95%) in order to prevent 90% of anthrax
cases. Post-exposure vaccination, however, can shorten the du-
ration of an antibiotic regimen. An article published in Nature
written by Ron Brookmeyer, Elizabeth Johnson,  and Robert
Bellinger, concludes that treating patients with antibiotics and
post-exposure vaccination is more practical and that the most
efficient way of preventing anthrax is heightened awareness of
clinical  symptoms,  surveillance, and mass  antibiotic distribu-

            Figure 6-5. Cutaneous anthrax infection: when infection occurs after entering the skin, symptoms are a raised
            itchy bump that develops into a vesicle and then a painless ulcer.
6.2.1  Message Maps about the Anthrax Bioterrorism Event

Message Map 1: Overarching Message Map
This is an overarching message map, and it contains information the public most needs to know about the anthrax: how it was used as
a bioterrorist tool, the symptoms of anthrax infection, and the three methods of infection (inhalation, cutaneous, gastrointestinal).
Stakeholder: Public/Media
Question or Concern: Overarching Message Map - What does the public most need to know?
Key Message 1
Anthrax bioterrorism event in fall 2001
Supporting Information 1-1
Anthrax spores transmitted through postal ser-
vice letters
Supporting Information 1-2
22 cases, 5 deaths (all from inhalation)
Supporting Information 1-3
Treatable with antibiotics if diagnosed early
Key Message 2
Symptoms of anthrax infection
Supporting Information 2-1
Inhalation: initial cold-like symptoms, progress-
ing to severe breathing problems, death
Supporting Information 2-2
Cutaneous: raised itchy bump that resembles
a bite or skin infection
Supporting Information 2-3
Gastrointestinal: nausea, loss of appetite, fe-
ver, severe diarrhea
Key Message 3
Three methods of transmission
Supporting Information 3-1
Inhalation (lungs)
Supporting Information 3-2
Cutaneous (skin)
Supporting Information 3-3
Gastrointestinal (digestive)
Message Map 2: What happened? What should the public know?
In this case, the message map describes the anthrax event of 2001: how many people were infected, how the anthrax spores were
transmitted, and three methods of clinical infection.
Stakeholder: Public/Media
Question or Concern: What happened (Who, what, when, where, why?) What should the public know?
Key Message 1
Anthrax bioterrorism event in fall 2001
Supporting Information 1-1
22 people were infected
Supporting Information 1-2
1 1 inhalation cases, 1 1 cutaneous cases
Supporting Information 1-3
5 deaths, all from inhalation of anthrax
Key Message 2
Anthrax spores transmitted through postal
service letters
Supporting Information 2-1
Letters sent to Florida, NYC, and D.C.
Supporting Information 2-2
All of the identified letters mailed from Trenton,
Supporting Information 2-3
Sender of letters is still unknown
Key Message 3
Letters sent to media and political figures
Supporting Information 3-1
American Media Inc.
Supporting Information 3-2
Tom Brokaw
Supporting Information 3-3
Senator Tom Daschle

Message Map 3: How did you find out about the anthrax bioterrorism?
This message map's key words are three key dates in the anthrax event of 2001: the first diagnosis, the date when anthrax spores were
discovered at American Media Inc., and October 9, when the first cutaneous case of anthrax was recognized.
Stakeholder: Public/Media
Question or Concern: How did you find out about anthrax?
Key Message 1
October 2, 2001 - first diagnosis
Supporting Information 1-1
Patient awoke October 2 with nausea, vomit-
ing, and confusion
Supporting Information 1-2
Patient worked at American Media Inc.
Supporting Information 1-3
Patient died October 4
Key Message 2
October 4, 2004 - Evidence of B. anthracis at
American Media Inc.
Supporting Information 2-1
Second AMI employee diagnosed on October
Supporting Information 2-2
Second employee worked in the mailroom
Supporting Information 2-3

Key Message 3
October 9, 2004 - First cutaneous case of an-
thrax recognized
Supporting Information 3-1
Patient worked in mail-room for anchorman
Tom Brokaw
Supporting Information 3-2
Marked by skin lesions
Supporting Information 3-3
NJ postal workers diagnosed with cutaneous
and inhalation anthrax on October 13
Message Map 4: What are the health effects associated with anthrax?
Anthrax has three modes of transmission, with different symptoms. This message map's key words are the three modes of transmis-
sion: cutaneous, inhalation, and gastrointestinal. The supporting information describes the symptoms and prognosis of the cutane-
ous anthrax, inhalation anthrax, and gastrointestinal anthrax.
Stakeholder: Public/Media
Question or Coneern: What are the health effects associated with anthrax?
Key Message 1
Supporting Information 1-1
Small sore that develops into a blister, then a
skin ulcer
Supporting Information 1-2
Treated with antibiotics
Supporting Information 1-3
Usually not fatal
Key Message 2
Supporting Information 2-1
1-6 day incubation period; biphasic illness
- having two distinct phases
Supporting Information 2-2
First phase: flu-like symptoms, then rapid de-
Supporting Information 2-3
Second phase: rapid deterioration, and death.
Can be fatal
Key Message 3
Supporting Information 3-1
Consumption of contaminated meat
Supporting Information 3-2
Nausea, loss of appetite, bloody diarrhea, fe-
ver, stomach pain
Supporting Information 3-3
Death in 25%-60% of cases

Message Map 5: What can people do to prevent an anthrax infection?
Since anthrax was sent by mail, this message map is a guideline of how to handle mail, both for the public at large and postal work-
ers. The third key message is steps to take if you think you have been exposed.
Stakeholder: Public/Media
Question or Concern: What can people do to prevent anthrax infection?
Key Message 1
Supporting Information 1-1
Do not open suspicious mail
Supporting Information 1-2
Keep mail away from face when opening it; do
not sniff
Supporting Information 1-3
Wash hands afterwards
Key Message 2
Postal workers56
Supporting Information 2-1
Wear protective, impermeable gloves
Supporting Information 2-2
Avoid touching eyes, skin, or other mucous
Supporting Information 2-3
Wear long-sleeved clothing and pants to pre-
vent skin exposure
Key Message 3
If you have been exposed ...
Supporting Information 3-1
Call the doctor right away
Supporting Information 3-2
Antibiotic treatment
Supporting Information 3-3
Post-exposure vaccination
Message Map 6: What is being done to prevent anthrax outbreaks in the future?
The methods of preventing anthrax attacks in the future fall into three categories which serve as the three key messages for this mes-
sage map: surveillance, education, and equipping.
Stakeholder: Public/Media
Question or Concern: What is being done to prevent anthrax outbreaks in the future?
Key Message 1
Supporting Information 1-1
State and local governments
Supporting Information 1-2
Health departments, hospitals
Supporting Information 1-3
National electronic tracking database
Key Message 2
Supporting Information 2-1
General public awareness
Supporting Information 2-2
Postal workers
Supporting Information 2-3
Physicians so they can better recognize the
clinical symptoms
Key Message 3
Equipping (Bioshield Act)
Supporting Information 3-1
Safe laboratories for testing
Supporting Information 3-2
Supporting Information 3-3
Post-exposure vaccine

6.3    Water Contamination
        (Cryptosporidium): Crisis Summary
        and Message Maps

Time and location of event:
April 1993,  in Milwaukee, Wisconsin.  Outbreak sickened
403,000 people and 111 people died. Elderly and immuno-com-
promised individuals were most at risk.

Cryptosporidiosis - a background:
Cryptosporidiosis  is a disease caused by the protozoan Cryp-
tosporidium parvum.  Its mode  of transmission is  fecal-oral
(infection-laden stool from one person gets into the mouth of
another). This can happen from improper sanitation,  as well as
drinking contaminated water. An oocyst is a dormant form of
the protozoa. An oocyst is 2 to 6 microns in diameter. Once an
animal or  person is infected, the parasite lives in the intestine
and passes into the stool. Millions of Cryptosporidium oocysts
can be released in a bowel movement from an infected animal
or human.  Feces from an infected animal or human can contam-
inate water sources, which is the suspected cause in the Milwau-
kee outbreak. Cryptosporidium is often found in rivers, lakes,
and streams contaminated with animal feces or which  receive
wastewater from a sewage plant. Prevalence of Cryptosporidi-
osis among calves and other livestock is particularly high.

Overall  there are three pathways of fecal/oral transmission/in-
  1) Transmission via water and food
  2) Animal-to-person transmission
  3) Person-to-person transmission

Cryptosporidium has many  features that make it a very chal-
lenging  contaminant to control.  The parasite is protected by
an outer shell that makes it resistant to chlorine-based disin-
fectants. The shell also allows the oocysts to live outside the
body  for a long time.57 The ingestion of as few as 10 oocysts
is enough to produce an infection.58 Even more troublesome is
the fact  that to date there is no safe and effective treatment for

Cryptosporidium parvum oocysts have been recognized as a
human pathogen since 1976.60 In 1982, the number of report-
ed cases began to increase dramatically as part of the AIDS
epidemic, as immuno-compromised individuals  are less able
to ward off Cryptosporidiosis. The Milwaukee outbreak is the
largest in the United States, but there have also been outbreaks
associated with swimming or amusement parks. In 1997 there
was an outbreak of Cryptosporidiosis associated with a water
sprinkler fountain in Minnesota.61

First indicators of epidemic:
Milwaukee has two main water treatment  plants: one located
in the northern part of the city, the other in the southern part of
the city. The water supply is from Lake Michigan. The southern
plant predominantly serves the southern part of the city. These
plants  collectively are known as the Milwaukee  Water Works

Starting on March 21, 1993, plant records revealed an increase
of turbidity on the southern plant. Turbidity refers to how clear
the water is. The greater the amount of total suspended solids
(TSS)  in the water, the murkier it appears and the higher the
measured turbidity. From January 1983 through January 1993,
the turbidity of treated water did not exceed 0.4 nephelometric
Figure 6-6. The protozoan Cryptosporidium parvum.
                                                            Figure 6-7. The life cycle of Cryptosporidium and how the oocysts
                                                            enter the human body.

turbidity unit (NTU). An NTU is used to measure turbidity of
water, as turbidity is often an indicator of contamination (in this
case, from Cryptosporidium oocysts). From March 23  to April
1, 1993,  the maximal daily turbidity of treated water was con-
sistently  0.45 NTU or higher, with a peak of 1.7 NTU on March

Meanwhile, on Thursday, April 1, 1993, a pharmacist in Mil-
waukee noted a dramatic increase in sales of over-the-counter
anti-diarrheal and anti-cramping medications. Normally, his
drugstore sold $30 a day of these medications. Starting April
1, the pharmacy drug  sales increased to approximately $500
to $600 a day. The pharmacist contacted the health department
to inquire about unusually  frequent reports of gastrointestinal

On April 5, the Wisconsin Division of Health was contacted by
the Milwaukee Department of Health after widespread  cases of
gastrointestinal illness, absenteeism among teachers, students,
and hospital workers.  On April 7, the laboratories identified
Cryptosporidium oocysts in stool samples from seven adults in
the Milwaukee area. By April 7, there was an advisory to Mil-
waukee residents to boil their water, and the southern plant was
closed on April 9. Overall an estimated 403,000 people were in-
fected, 4,400 people were hospitalized, and 111 people  died.62

Clinical  features of cryptosporidiosis:
Cryptosporidiosis is transmitted by  ingestion of oocysts ex-
creted in the feces of humans or animals. Cryptosporidiosis has
three methods of transmission:  1) via water and food; 2) ani-
mal to person; and 3) person-to-person.64 The incubation period
is approximately 2 to  10 days.  Children under two years old,
immuno-compromised individuals65'66 and the elderly67 have a
greatly increased chance of serious sickness from Cryptospo-

The most common symptom of cryptosporidiosis  is watery
diarrhea.  Other symptoms  include: dehydration,  weight loss,
stomach  cramps or pain, fever, nausea and  vomiting.  Some
people with cryptosporidiosis will be asymptomatic (without
noticeable clinical symptoms). In healthy individuals the symp-
toms will typically last for about 1 to 2 weeks. However, in per-
sons whose immune system is weakened, cryptosporidiosis can
be serious, long-lasting, and even fatal.68 Cryptosporidiosis is
often misdiagnosed as "stomach flu."

What can you do to prevent cryptosporidiosis68?
  • Wash hands frequently
  • Practice safer sex
  • Avoid touching farm animals
  • Avoid touching the stool of pets
  • Avoid swallowing water while  swimming in the ocean,
    lakes, rivers, or pools, and when using hot tubs
  • Wash or cook food thoroughly
  • Drink safe water. Boiling and filtering water tends to get rid
    of the Cryptosporidium oocysts, but not  all filters are ef-
    fective - look for the words "reverse osmosis," or absolute
    pore size of one micron or  less, or one that has been NSF
    rated for "cyst approval"
   Dally age-ad)UBCed rate (+ standard deviation)  of GIB
         per 100,000 elderly during the  Hilvaufcee
                cryptospormiosis outbreak
       Horth plwtt
       1.03 4- 2.7
Central, «re«
1.3-* * l.t
Sooth plant
2,33 •_ 2.6
Figure 6-8. The Southern plant of Milwaukee Water Works predomi-
nantly serves the southern  part of the city. In 1993 water from the
southern plant became contaminated with Cryptosporidium oocysts,
causing many hospitalizations, especially in the elderly and immuno-
compromised. As the picture above shows, there were less gastrointes-
tinal hospitalizations in the northern and central areas of the city.
What can be done to prevent future outbreaks?
The main method of preventing future outbreaks is improved
water-treatment technologies. Cryptosporidium oocysts have a
tough wall that makes them resistant to traditional methods of
disinfection, such as chlorination. The most effective methods
of removal are filtration and ozone treatment.69 However, many
cities (Boston, Seattle, Portland, and San Francisco) do not filter
municipal drinking water. In New York City, the Croton res-
ervoir is filtered, but the Delaware and Catskill reservoirs are
not.70 Since the Milwaukee incident, the practice of recycling
filter backwash water was eliminated. The Milwaukee plants
have also installed continuous turbidity monitors on each bed,
with an alarm sounding and the system shut down if the turbid-
ity of filtered water exceeds 0.3 NTU.62

Watershed protection is another method of preventing contami-
nation. Septic system regulations and control of runoff into sur-
face water reservoirs such as  lakes or streams can help keep
human and animal waste out of water supplies.

6-3,1  Message Maps for Cryptosporidium Infection

Message Map 1: Overarching Message Map: What does the public most need to know?
This message map touches upon three key messages: that there is an outbreak of cryptosporidiosis in Milwaukee, people most at risk
of becoming seriously ill from cryptosporidiosis, and the symptoms of the disease.
Stakeholder: Public/Media
Question or Concern: Overarching Message Map - What does the public most need to know?
Key Message 1
Outbreak of cryptosporidiosis in Milwaukee
Supporting Information 1-1
From contaminated water supply
Supporting Information 1-2
Two water treatment plants: southern and
Supporting Information 1-3
Southern plant reported increased turbidity on
March 21
Key Message 2
High risk groups are:
Supporting Information 2-1
Immuno-compromised (HIV+, diabetes)
Supporting Information 2-2
Supporting Information 2-3
Young children
Key Message 3
Symptoms and precautions
Supporting Information 3-1
Watery diarrhea most common symptom. Can
also have nausea, fever, vomiting
Supporting Information 3-2
Incubation period: 2-10 days
Supporting Information 3-3
Symptoms last 1 -2 weeks
Message Map 2: What happened? What should the public know?
This message map answers the "What happened?" questions. In this case, the Milwaukee Water Works' Southern plant was contami-
nated with Cryptosporidium oocysts, and an estimated 403,000 Milwaukee residents were infected.
Stakeholder: Public/Media
Question or Concern: What happened? (Who, what, when, where, and why?). What should the public know?
Key Message 1
Outbreak of cryptosporidiosis in Milwaukee
Supporting Information 1-1
Cryptosporidium is a protozoan (oocyst)
Supporting Information 1-2
Released from feces into water supply
Supporting Information 1-3
Oocyst resistant to chlorine treatment, can live
outside the body for long periods of time
Key Message 2
From contaminated water supply
Supporting Information 2-1
Southern plant reported increased turbidity on
March 21
Supporting Information 2-2
Two treatment plants: southern and northern
Supporting Information 2-3
Notice on April 7 to boil water
Key Message 3
403,000 people infected
Supporting Information 3-1
April 7 - stool samples from seven adults con-
firmed cryptosporidiosis
Supporting Information 3-2
Watery diarrhea main symptom
Supporting Information 3-3
1 1 1 deaths

Message Map 3: How did you find out about the Cryptosporidium outbreak?
Three main events led to the discovery of the Cryptosporidium contamination: water plants reported increased turbidity, there was
a spike in pharmaceutical sales of over-the-counter anti-diarrheal medicine, and there was widespread absenteeism in schools and
offices, which led to the Milwaukee Department of Health being contacted. On April 7 stool samples confirmed cryptosporidiosis.
Stakeholder: Public/Media
Question or Concern: How did you find out about the Cryptosporidium outbreak?
Key Message 1
Pharmaceutical sales
Supporting Information 1-1
Milwaukee pharmacist noticed a rise in OTC
anti-diarrheal medicine
Supporting Information 1-2
Normal sales: $30/day
Supporting Information 1-3
After April 1 sales: $500-$600 a day
Key Message 2
Water-treatment plant (MWW)
Supporting Information 2-1
Increased turbidity noted March 21, 1993 at
southern plant
Supporting Information 2-2
Normal turbidity: 0.45 NTU
Supporting Information 2-3
Outbreak period turbidity peaked at 1 .7 NTU
(March 28 and 30, 1993)
Key Message 3
Supporting Information 3-1
Among teachers, students, and hospital work-
Supporting Information 3-2
Absentees all had gastrointestinal illness
Supporting Information 3-3

Message Map 4: What are the health effects of cryptosporidiosis?
This message map is straightforward: its key messages are the main symptom of cryptosporidiosis, the modes of transmission, and
the groups of people who are most at risk of serious illness from Cryptosporidium.
Stakeholder: Public/Media
Question or Concern: What are the health effects associated with exposure to Cryptosporidium?
Key Message 1
Watery diarrhea
Supporting Information 1-1
Incubation period: 2-10 days
Supporting Information 1-2
Symptoms last 1 -2 weeks
Supporting Information 1-3
Can have dehydration, nausea, fever, stomach
pain, vomiting. Some people show no symp-
Key Message 2
Three modes of fecal-oral transmission
Supporting Information 2-1
Eating/drinking contaminated food or water
Supporting Information 2-2
Animal-to-person (fecesfrom animal somehow
gets into food/water)
Supporting Information 2-3
Key Message 3
High risk groups
Supporting Information 3-1
Immuno-compromised, elderly, children under
the age of 2
Supporting Information 3-2
Illness can be very serious and prolonged, with
no known treatment
Supporting Information 3-3
Death may result

Message Map 5: What can people do to prevent Cryptosporidium infection?
The ways to prevent infection fall under three categories: safe-drinking water habits, good hygiene/sanitation, and avoiding touching
farm animals.
Stakeholder: Public/Media
Question or Concern: What can people do to prevent Cryptosporidium infection?
Key Message 1
Safe-drinking water habits
Supporting Information 1-1
Pay attention to public announcements about
Supporting Information 1-2
Filter water (NSF rated for "cyst approval" or
pore size of one micron or less)
Supporting Information 1-3
Boil water for persons that are immunocom-
Key Message 2
Good hygiene/sanitation
Supporting Information 2-1
Wash hands, especially after bowel movement
or changing diapers
Supporting Information 2-2
Practice safer sex
Supporting Information 2-3
Wash/cook food
Key Message 3
Supporting Information 3-1
Avoid touching farm animals
Supporting Information 3-2
Avoid touching the stool of pets
Supporting Information 3-3
Wash hands after picking up stool of pets
Message Map 6: What can be done to prevent this in the future?
The three ways to prevent future outbreaks of Cryptosporidium are: more vigorous water treatment (filtering, ozone treatment),
watershed protection (as fecal matter can easily wash into surface water reservoirs), and public awareness and surveillance.
Stakeholder: Public/Media
Question or Concern: What can be done to prevent this in the future?
Key Message 1
Water treatment
Supporting Information 1-1
Filter municipal water supplies
Supporting Information 1-2
Ozone treatment is effective
Supporting Information 1-3
Milwaukee plant automatically shuts down if
turbidity exceeds 0.3 NTU
Key Message 2
Watershed protection
Supporting Information 2-1
Septic system regulations (septic tanks not al-
lowed to run into lakes)
Supporting Information 2-2
Runoff control
Supporting Information 2-3
Difficult to do, especially around rural areas
with a lot of cattle and other livestock
Key Message 3
Public awareness and surveillance
Supporting Information 3-1
Monitor turbidity levels
Supporting Information 3-2
Boil water for high risk groups
Supporting Information 3-3
Filter water for high risk groups

Message Map 7: How did this happen?
Unmet water quality standards, inadequate diagnosis, and the existence of populations vulnerable to infection all contributed to the
1993 outbreak. Cryptosporidium oocysts passed through the city's filtration system, cryptosporidiosis was often misdiagnosed by
doctors, and immuno-compromised individuals became seriously ill.
Stakeholder: Public/Media
Question or Concern: How did this happen?
Key Message 1
Inadequate water treatment
Supporting Information 1-1
Cryptosporidium oocysts passed through
city's filtration system
Supporting Information 1-2
Marked turbidity in southern water treatment
Supporting Information 1-3
Northern plant not affected
Key Message 2
Inadequate diagnosis
Supporting Information 2-1
Diagnosed often as viral gastroenteritis or "in-
testinal flu"
Supporting Information 2-2
Many patients do not seek treatment for diar-
Supporting Information 2-3
No known treatment
Key Message 3
Three main vulnerable populations
Supporting Information 3-1
Elderly (often in nursing homes)
Supporting Information 3-2
Immuno-compromised (HIV+, etc.)
Supporting Information 3-3
Very young children

                                                7.  Conclusions
Risk communication is a relatively new concept of communi-
cating environmental and health hazards to the public. Much of
it was developed by Vincent Covello. The National Research
Council of the United States gave the  following definition of
risk communication:  "Risk communication is  an interactive
process of exchange of information  and opinions among in-
dividuals, groups, and institutions. It often involves multiple
messages about the nature of the risk or expressing concerns,
opinions, or reactions to risk messages or to the legal and insti-
tutional arrangements for risk management?

Different situations require different methods. Some situations
will have very high public outrage but little actual hazard, which
is a measure of the actual risk. Other situations will have the re-
verse situation. An important factor to consider in all risk com-
munication situations is risk perception. As a general rule, the
public tends to underestimate risks that are: not dreaded, vol-
untary, natural, scientifically well-known and well-understood,
controllable by the individual, in the hands of a reliable source,
reversible with immediate health effects, with adults as health
victims, unmemorable and without significant media attention,
and that pose no risk to the future population. The general pub-
lic tends to overestimate risks that are: dreaded, involuntary, in-
dustrial, scientifically unknown, controlled by others, managed
by an unreliable, irresponsible source, with irreversible, delayed
health effects, children as victims, catastrophic, that receive
media attention, and have a risk to future generations.

hi addition to applying risk perception information, risk com-
munication has "Seven Cardinal Rules," according to Covello:

Rule 1: Accept and involve the public as a legitimate partner
Rule 2: Listen to the audience
Rule 3: Be honest, frank, and open
Rule 4: Coordinate and collaborate with other credible sources
Rule 5: Meet the needs of the media
Rule 6: Speak clearly and with compassion
Rule 7: Plan carefully and evaluate performance
Message mapping is simply one of the useful tools used by risk
communicators to warn of hazards to the public. It consolidates
many of the rules of risk communication (speaking briefly, lim-
iting oneself to three key messages) and can be applied to many
situations, as shown in the examples in this paper. It helps orga-
nizations meet several risk communication goals:

  • Identify stakeholders early on in the communication pro-
  • Anticipate the questions and concerns of the stakeholders
    before they appear.
  • Organize our thoughts and ideas and prepare messages in
    response to the concerns and questions of the stakehold-
  • Develop key messages and supporting information in a
    context of clear, concise, transparent, and accessible frame-
  • Promote an open dialogue about the messages both inside
    and outside the organization.
  • Provide the spokesperson with a user-friendly guide.
  • Make sure that the organization has consistent information
    and messages.
  • Make  sure  that the organization  speaks with  a single

A message map is designed as a three tier grid, with emphasis
on the three key messages.

  • The top tier of the template identifies the audience for the
    message map  as well as the question or concern that the
    message map is intended to address.
  • The  second tier of the message map contains three key
    messages that answer the question or concern.
  • The third tier contains supporting information,  which is
    blocked in groups of 3 's under each key message. They can
    take the form of visuals, analogies, personal stories, hotline
    numbers, and/or citations of credible sources of  informa-

This template can be used during news conferences, presenta-
tions, or any area where the risk of a hazard needs to be com-


                                                  8.  Glossary
Arbovirus - Any of a large group of viruses transmitted by
arthropods, such as mosquitoes and ticks, that include the caus-
ative agents of encephalitis, yellow fever, and dengue.

Biphasic - Having two distinct stages (as in an illness).

Bridging  - A method used in risk communication to  reiter-
ate and clarify key points. For example, "/ want to remind the
public that the probability of death is very small if discovered

Cutaneous - Of, relating to, or affecting the skin. A cutaneous
transmission (such as for anthrax) means transmission through

Epizootic - Affecting a large number of animals  at the same
time within a particular region or geographic area. Used  of a

Fecal-oral - A method of transmission of disease in which the
infection-laden feces from one person finds its way into the
mouth of another person.

Flavivirus - A family of viruses transmitted by mosquitoes and
ticks that cause some important diseases, including dengue, yel-
low fever, tick-borne encephalitis virus, and West Nile fever.

Hazard - Experts' assessment of risk.

Immuno-compromised - Having an immune system that has
been impaired by disease or treatment. Most often used in con-
nection with infections such as AIDS or HIV+ status.

Incubation Period - The amount of time between infection to
the onset of clinical symptoms.

Key Message - Information that the target audience most needs
or wants to know.

Message Map - A detailed, hierarchically organized response
to anticipated questions or concerns during a crisis/event.

Myalgia - Muscle pain or tenderness.

Oocyst - A thick-walled structure in which sporozoan zygotes
develop and that serves to transfer them to new hosts. An ex-
ample of an oocyst would be the Cryptosporidium oocysts.

Outbreak - A sudden increase in the prevalence of a disease. In
1993 Milwaukee had an outbreak of cryptosporidiosis.

Outrage - Public perception of how substantial or alarming a
risk is.

Overarching Message Map - The message map that contains
the organization's core message. The focus is on what people
most need to know about the situation or topics, and provides an
opening statement at a press conference, presentation, or news

Protozoa - Any of a large group of single-celled, usually mi-
croscopic,  eukaryotic organisms, such  as amoebas, ciliates,
flagellates, and sporozoans.

Radon -A toxic, colorless gas that comes from the decay of ra-
dium and uranium found in the soil/earth/rock. This toxic, col-
orless gas can seep into residences. Different geographic areas
will have different levels of radon. Radon is  a carcinogen and
can cause lung cancer.71

Risk - Judgment concerning the likelihood, severity,  or impor-
tance of a threatening event or condition;  the probability of loss
of which people value.

Risk Perception  - The subjective perception of risk/danger.
Not necessarily correlated with actual risk.

Risk Communication - An interactive process in which infor-
mation and opinions are exchanged among individuals, groups,
and institutions in response to  an event or a risk.

Sound Bite - A short phrase or sentence that deftly captures the
essence of the speaker's main message.

Stakeholder - All interested,  affected, or influential  parties in
an event, usually including the public at large.

Turbidity - The cloudiness of the water. The greater the amount
of total suspended solids (TSS) in the water, the murkier it ap-
pears and the higher the measured turbidity.


       9.  Most Frequently Asked Questions by Journalists During a Crisis
1.   What is your name, title, job responsibilities and qualifica-
2.   Can you tell us what happened, and when and where it hap-
3.   How many people were harmed?
4.   Are those that were harmed getting help?
5.   How certain are you about this information?
6.   Is the situation under control?
7.   Is there any immediate danger?
8.   What is being done in response to what happened?
9.   What are you advising people to do?
10. How long will it be before the situation returns to normal?
11. Can the situation worsen? What is the worst case scenar-
12. What help has been requested or offered from others?
13. What responses have you received?
14. How much damage occurred and what additional damage
    do you expect?
15. Who else is involved in the response?
16. Why did this happen?
17. What was the cause?
18. Did you have any forewarning that this might happen?
19. Can the situation worsen?
20. If you are not sure of the cause, what is your best guess?
21. Who is to blame?
22. Could this have been avoided?
23. Do you think those  involved  handled the situation well
24. Who is conducting the investigation?
25. What have you found out so far?
26. Why was more not done to prevent this from happening?
27. What is your personal opinion?
28. Are people overreacting?
29. Has anyone broken the law?
30. What are you not telling us?
31. What effects will this have on the people involved?
32. What precautionary measures were taken?
33. Do you accept responsibility for what happened?
34. Has this ever happened before?
35. Can this happen elsewhere?
36. What lessons were learned and were they implemented?
37. What can be done to prevent this from happening again?
3 8.  What would you like to say to those that have been harmed
    and their families?
39.  Are people out of danger? Are people safe?
40.  Will there be inconvenience to employees or to the public?
41.  How much will all this cost?
42.  Are you able and willing to pay the costs?
43.  Who else will pay the costs?
44.  What does this all mean?
Figure 9-1. In crisis situations, journalists and reporters always want
answers, NOW!


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