CRISIS AND RISK COMMUNICATION:
PUBLIC HEALTH ISSUES OF HAZARD, OUTRAGE, AND EBOLA VIRUS
by
Rachel Taber
BS, Western Washington University, 1998
PhD, University of Pittsburgh, 2006
Submitted to the Graduate Faculty of
Graduate School of Public Health in partial fulfillment
of the requirements for the degree of
Master of Public Health
University of Pittsburgh
2014
UNIVERSITY OF PITTSBURGH
Graduate School of Public Health
This essay is submitted
by
Rachel Taber
on
December 11, 2014
and approved by
Essay Advisor:
Lawrence Kingsley, DrPH
______________________________________
Professor
Department of Infectious Diseases and Microbiology
Graduate School of Public Health
University of Pittsburgh
Essay Reader:
Elizabeth Felter, DrPH
______________________________________
Visiting Associate Professor
Behavioral and Community Health Sciences
Graduate School of Public Health
University of Pittsburgh
ii
Copyright © by Rachel Taber
2014
iii
Lawrence Kingsley, DrPH
CRISIS AND RISK COMMUNICATION:
PUBLIC HEALTH ISSUES OF HAZARD, OUTRAGE, AND EBOLA VIRUS
Rachel Taber, MPH
University of Pittsburgh, 2014
ABSTRACT
This essay presents issues pertinent to crisis and emergency risk communication for future public
health leaders in the infectious disease field. The technique includes an educational component
and methods to remove barriers to communication. The relevance of risk communication to the
field is that this method facilitates the presentation of accurate information that the public can
comprehend and act upon to make informed health decisions. Infectious disease experts
understand the science inherent to a health hazard (e.g. pathogens) and are trained in public
health practice. Informing the public about health risks is increasingly falling to public health
leaders who have no training in effective communication methods. This means the public can
misinterpret risks because they do not have, or do not comprehend, the information needed to
calculate their risk. Additionally, experts calculate biological risks differently than the public.
The public interprets risk as the hazard plus or minus the emotional termed “outrage” the hazard
invokes. Social and psychological factors, as well as a person’s background and previous
exposure, influence perceptions of risk. These aspects must be understood and overcome to
allow for effective risk communication. A number of theories address why people react
differently and provide insight into countering both outrage and social and psychological factors
and the person delivering the message can also influence perception of risk. The spokesperson
represents the experts and must be perceived as empathetic, honest, and knowledgeable to gain
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the public’s trust. Effective risk communication enables the public to comprehend the message,
remember the material, act on recommendations, provide feedback, and help guide future
programs and policies. Risk communication allows the public to safeguard their own health and
provides information to improve future communication and to build programs and policies the
public can embrace. Using the introduction of Ebola virus to the United States as an example of a
health risk this essay presents some of the barriers to effective communication and introduces
methods to overcome them.
v
TABLE OF CONTENTS
PREFACE ..................................................................................................................................... X
1.0
INTRODUCTION ........................................................................................................ 1
2.0
RISK = HAZARD + OUTRAGE ................................................................................ 4
2.1
HAZARD .............................................................................................................. 5
2.1.1
FILOVIRIDAE FAMILY ............................................................................... 6
2.1.1.1 Structure ................................................................................................ 7
2.1.1.2 Entry and Replication ........................................................................... 9
2.1.1.3 Transmission.......................................................................................... 9
2.1.1.4 Clinical Signs and Pathogenesis ......................................................... 13
2.1.1.5 Survival ................................................................................................ 14
3.0
OUTRAGE ................................................................................................................. 16
3.1
OUTRAGE FACTORS ..................................................................................... 17
3.2
UNDERSTANDING OUTRAGE ..................................................................... 19
4.0
5.0
3.2.1
The Mental Noise Theory.............................................................................. 19
3.2.2
Trust Determination Theory ........................................................................ 20
3.2.3
Social Amplification of Risk Framework .................................................... 21
3.2.4
Crisis and Emergency Risk Communication (CERC) theory ................... 22
COUNTERING PERCEPTIONS OF RISK ........................................................... 24
4.1
SPOKESPERSON ............................................................................................. 24
4.2
SPOKEN WORD ............................................................................................... 29
CONCLUSION........................................................................................................... 37
vi
BIBLIOGRAPHY ....................................................................................................................... 40
vii
LIST OF TABLES
Table 1. Risk Perception. .............................................................................................................. 17
viii
LIST OF FIGURES
Figure 1. Schematic representation of filovirus particle. ................................................................ 6
Figure 2. Szchematic representation of filovirus genome. ............................................................. 8
Figure 3. CDC poster. Safe removal of Personal Protective Equipment (PPE). .......................... 12
Figure 4. Previous 90 day Google Trend graph of Ebola searches. .............................................. 35
ix
PREFACE
I would like to thank Larry Kingsley for his support throughout my tenure in this program. I
appreciate his sharing his time and wisdom with me, his suggestions were always helpful. I would
like to thank Elizabeth Felter, who opened her classroom to me and provided me with helpful
discussions at a moment’s notice. I would also like to thank Martha Terry, Chelsea Palladino,
David Ko, Jim Keener, and Linda Frank. Together these people enriched my Masters experience
in innumerable ways and I will strive to “pay their support forward” as I can never pay it back. I
would also like to acknowledge my fellow classmates and the dedicated instructors who
generously shared their expertise with me, a wonderful group of people. I look forward to using,
refining, and expanding the knowledge I have acquired at the Graduate School of Public Health.
Family and friends share their love and I remain eternally grateful.
This one isn’t for you Bill LOL.
x
1.0
INTRODUCTION
Guinea, Sierra Leone, and Liberia have been experiencing an Ebola virus (or Ebola) disease
outbreak that started in late 2013. On September 19th, 2014 a Liberian man entered the U.S. to visit
his family and had no indications of Ebola virus infection; his temperature registered as normal
upon being checked immediately prior to his departure, per protocol, in Liberia. Approximately
four day after his arrival in Texas he went to an emergency room with clinical symptoms and was
diagnosed with “a common viral infection” and sent home. September 28th, no longer able to move
unaided, he returned to the hospital via ambulance. He was admitted and subsequently placed in
isolation. An Austin public health laboratory discovered Ebola virus in his blood sample and a
Centers for Disease Control and Prevention (CDC) laboratory confirmed this finding on the 30th
of September. This was the first time Ebola virus infection had been diagnosed in the U.S.
Until the diagnosis in Texas the majority of the U.S. population had only experienced Ebola
virus infection in the abstract, a disease outbreak in Africa far from their shores. When reporting
on the outbreak the U.S. media provided daily updates on the number that had succumbed to
infection, described frightening disease symptoms, and explained how hard it was to combat the
spread of the virus through standard procedures. People seemingly wrapped head-to-toe in
protective clothing were shown caring for the sick, then reportedly succumbing to infection.
Suddenly, with Ebola virus in the U.S. Americans thought they too could become infected.
1
They were correct. Anyone can be infected with Ebola through exposure to infectious virus.
Infection is possible, however, it is not likely for the overwhelming majority of the U.S. population
because they will not come in contact with the virus. The CDC has a mission to protect the health
of American citizens so informing the American public about their individual health risk posed by
the virus fell to the CDC. This is partially accomplished by educating the public using risk
communication techniques. A ranking of hazards that kill people and a ranking of hazards that
upset them often have very little in common (V. T. Covello, Peters, Wojtecki, & Hyde, 2001; P.
Sandman, 2000p. 2). Risk communication attempts to address this discrepancy. There are
impediments to communicating risk that have to be overcome to ensure a message can be
understood and acted upon. First, and importantly, people do not all process information in the
same way. An individual’s prior experiences, culture, and emotions impact how information is
comprehended. Research has also shown that people who are under stress have decreased ability
to understand and remember what they have heard (V. T. Covello et al.). Lastly, the public has
increasing access to biological and health information from a number of sources that may not be
accurate. Countering misinformation is very difficult but must be accomplished to ensure decisions
are based on accurate information. The task of communicating factual information to specific
audiences that they can comprehend and use increasingly falls to public health professionals, often
professionals with little or no knowledge of risk communication. To allow public health
professionals a greater ability to surmount these obstacles this essay provides an overview of risk
communication for infectious disease professionals. This will support better communication
opportunities to lower disease burden in the populations they serve. Armed with an understanding
of the elements that impede comprehension a strategy that overcomes these barriers can be
2
developed. The diagnosis of Ebola virus in the United States is used as the risk example however
the material is applicable to other health hazard.
The definitions of risk are many and varied (Hampel, 2006) but a general definition was
provided by Glik; “health risks caused by environmental, industrial, or agricultural processes,
policies, or products among individuals, groups and institutions” (Barbara Reynolds, Centers for
Disease, & Prevention, 2002). The purpose of risk communication is to inform the public about
the level of risk (low or high), the significance of the risk (trivial or urgent), and the action or
behaviors to take in controlling or minimizing risk. Crisis is defined as “risk manifest” (Barbara
Reynolds, Centers for Disease, et al., 2002), an unexpected event that requires an immediate
response. Risk communication provides warnings and how to minimize danger while crisis
communication is designed to decrease the negative outcomes of an event and provide strategies
to reduce harm. Informing the public about Ebola virus in the U.S. involves both of these
disciplines thus this essay uses the terms risk communication and crisis and risk communication
interchangeably.
The purpose of crisis and risk communication is not to eliminate dissent rather to inform
the public (Vincent T Covello & Allen, 1994) This form of communication is interactive thus the
public becomes a cooperating partner providing input and endorsement in the development of
policy (Vincent T Covello & Allen, 1994). This discipline allows public health officials to be
proactive in reporting, rather than reacting to events. This enables a more accurate reporting of
the message through the media. This method of communication was developed because research
has demonstrated that during times of stress people’s ability to comprehend information and make
well-reasoned decisions becomes impaired.
3
2.0
RISK = HAZARD + OUTRAGE
A calculation of risk for many experts is risk = hazard. Virologists, infectious disease public
health experts, and others trained in science perceive the hazard alone, Ebola virus. Experts
perceive the severity of the risk technically as dispassionate facts regarding Ebola virus. They
include infection, transmission, pathogenesis, case fatality rate, transmission, and inactivation into
their calculation of risk. The above formula, risk = hazard + outrage, penned by Peter M.
Sandman in the late 1990’s, describes how risk is perceived by the public (P. M. Sandman &
American Industrial Hygiene Association.). The public includes factors such as feeling and
personal experience into their calculation. These additional factors are termed “outrage” and can
enhance the public’s perception of risk.
In Sandman’s equation of risk, hazard is defined as the magnitude multiplied by the
probability of a particular risk happening. Although confusing, as the word “hazard” has different
definitions, Sandman uses the term because he has not found a better substitute (P. Sandman &
Lanard). Webster’s New Collegiate Dictionary defines the word hazard as “a source of danger”.
Dangers can be real or imagined and Ebola virus infection is especially dangerous in a setting with
poor health care infrastructure as was seen in the 2014 outbreak. The outbreak received extensive
media coverage due to a number of reasons. Lack of equipment and overcrowded conditions
increased the difficulties in blocking viral transmission. The number infected and killed grew daily
(greater than 17,000 confirmed or suspected cases as of November 30th, 2014 accounting for over
6,000 deaths), death from untreated infection was described as rapid and gruesome, and the
American public wanted more information because the threat of infection was no longer abstract,
the virus was in Texas.
4
2.1
HAZARD
Ebolavirus was first reported to the international press in 1976 through simultaneous outbreaks in
Zaire (now Democratic Republic of the Congo – DRC) and Sudan (South Sudan). The outbreaks
were repeated in 1977 and 1979 respectively. There was no further international attention until an
outbreak in 1989 in a nonhuman primate facility in Reston, VA. The outbreak was reported in The
New Yorker (Preston) and caused subclinical infection in humans but infection killed monkeys.
Further lethal Ebola virus outbreaks in human occurred sporadically until 1994. As of 2013 the
virus had been responsible for 1,586 deaths in total with fatality rates ranging from 50% to 90%
(CDC).
On March 10th, 2014 the Guinean Ministry of Health was notified of a mysterious illness,
later identified as Ebola virus, with a high fatality rate. Correct diagnosis of the illness was
hindered by the similarity of symptoms to endemic diseases (e.g. malaria, typhoid) and medical
personnel did not recognize the agent. Médecins sans Frontières (MSF) set up medical support
facilities and alerted their leading infectious disease expert. He suspected a hemorrhagic fever
virus, either Marburg or Ebola (WHO). On March 23rd, 2014 the international media was alerted
to the Ebola outbreak. Previous outbreaks had occurred in remote areas but this outbreak began
where people were highly mobile. This allowed the virus spread to large cities early in the
epidemic, thereby hindering containment efforts. The World Health Organization (WHO) declared
an international health emergency on August 8th, 2014.
5
2.1.1 FILOVIRIDAE FAMILY
Ebola virus is a member of the filoviridae family that includes the Marburg virus. The Latin word
for thread, filum, gives the viruses their name as virions are filamentous to bacilliform (see Figure
1). The Marburg genus contains only the Lake Victoria marburgvirus species revealing its limited
genetic diversity. The Ebolavirus genus (the name of the Ebola virus genus) currently contains
five species. The first four are listed in decreasing order of virulence for humans; Zaire ebolavirus
(frequently referred to as ZEBOV in literature), Sudan ebolavirus, Bundibugyo ebolavirus, Tai
Forest ebolavirus, all with African origin, and Reston ebolavirus originating in the Philippines
Used with permission Swiss Institute of Bioinformatics (Hulo et al.)
Figure 1. Schematic representation of filovirus particle.
(Nelkin, 1989).
There is no vaccine, antiviral therapy, or approved treatment for Ebola virus infection thus
the public associates’ infection with a high risk and high outrage. The American public has also
been told that the CDC has strict classifications for filoviruses (e.g. Biosafety Level 4 pathogens
6
or “select agent”). These classifications restrict acquisition of the virus and federal law regulates
use of the virus. The restrictions require work with the virus to be carried out within specialized
containment facilities. There rigorous entry and exit procedures, individual oxygen supplies, and
negative air pressure. These characteristics and regulations regarding the virus can increase the
public’s perception of risk from Ebola infection.
The expert’s perception of risk is different than the publics because experts know
transmission can be easily blocked with adequate barrier nursing methods. This means the
probability of infection is almost zero to the majority of people in the U.S. because they have to
come in contact with the virus. Additionally Ebola is an enveloped virus, the envelope is made of
the same fragile membrane that hold our body’s cells together. Damage to the membrane
inactivates the virus so high heat (autoclaving at 60°C for 30 minutes) or by ultra-violet (sunlight)
radiation can render the virus noninfectious (Mitchell & McCormick; Mwanatambwe et al.). The
virus is also susceptible to numerous cleaning solutions (Mitchell & McCormick). The CDC
recommends the use of hospital disinfectants for viruses that are harder to inactivate (non-envelope
viruses such as poliovirus or rotavirus) (CDC). Cleaning surfaces with a 1:10 dilution of household
bleach for 10 minutes will also disinfect surfaces.
2.1.1.1 Structure
The virions (virus particles) measure approximately 1,200 nm (Geisbert & Jahrling) with a
diameter of 80 nm so they are not seen with the naked eye. Virions contain a single-strand,
linear, negative–sense RNA genome in a helical nucleocapsid (NC) or helical ribonucleoprotein
complex. NC protects the genome and provides the means to replicate the virus (see Figure 1).
NC is surrounded by matrix protein and a host derived outer envelope of plasma membrane. The
7
envelope contains anchored peplomers of the viral envelope glycoprotein (GP) that are used to
attach to host cells.
The genome, approximately 19,000 bases, encodes seven proteins (see Figure 2):
nucleoprotein (NP), viral protein 35 (VP35), VP40, GP, VP30, VP24, and polymerase (L). The
structural proteins of Ebola can be divided into two categories, those that make-up NC and those
associated with the viral envelope. Proteins that make up NC: NP, VP30, VP35 and L, transcribe
and replicate the genome in association with the viral RNA. Proteins associated with the envelope
are involved in virus assembly and cellular entry.
Used with permission Swiss Institute of Bioinformatics (Hulo et al.).
Figure 2. Schematic representation of filovirus genome.
GP is responsible for receptor binding and fusion between the viral envelope and cellular
membrane that allows entry into host cells (Wool-Lewis & Bates, 1998). GP is also involved in
pathogenicity (causing disease) and is studied for its antigenicity (ability to induce an immune
response) as well as a vaccine target. GP is heavily glycosylated, and like the HIV envelope protein
is shielded from immune recognition (Schlech, Lee, Cook, Rozee, & MacIntosh). The virus also
expresses a soluble, truncated form of GP (sGP). Antibodies made to sGP are non-neutralizing
thereby allowing the virus an immune escape mechanism (Wong, Kobinger, & Qiu). The sGP are
also believed to bind neutralizing antibodies adding another immune escape mechanism. The
ability to escape the immune response means Ebola virus infection is more deadly than infections
with viruses that are unable to do so.
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2.1.1.2 Entry and Replication
GP has been shown to bind a variety of host cell receptors giving the virus a broad tropism (Wilson
et al., 2000). Additionally, the virus can enter host cells through more than one route. Entry through
endocytosis (Takada et al.; Ye et al.), macropinocytosis (Aleksandrowicz et al.), and cholesterol
transport mechanisms have been reported (Carette et al.). After entry viral mRNA is transcribed
from the viral genome. This leads to a buildup of viral proteins that is believed to trigger the switch
from transcription to replication. Antigenomic templates are produced and serve as templates for
genomic RNA. This RNA is encapsidated and the subsequent decrease of capsid proteins then
initiates a switch back to transcription. This switch is repeated and eventually reaches a point where
replication and transcription occur simultaneously (Feldmann) and the virus is replicated and can
infect another cell. Replication in a number of different cell types results in large amounts of virus
being produced. High rates of replication leads to rapid disease and death.
2.1.1.3 Transmission
Non-human primates are infected with the same virus that infects humans (Ye et al., 2006) but
they are not the viral reservoir. The reservoir is a species that is infected with the virus but is not
killed by infection. A reservoir species allows the virus to continue to exist and be passed on. If
everything that was infected with the virus died the virus would cease to exist. Fruit bats are
believed to be the reservoir for the African ebolavirus (Gatherer). Philippine pigs are believed to
be the reservoir species for Reston ebolavirus (Weingartl et al.). After infection in a susceptible
host (non-reservoir host) the virus is amplified (replicated) and spreads through direct person-toperson (person-to-animal) contact or from contact with contaminated surfaces (e.g. clothing, nonsterilized medical equipment) and mucous membranes (e.g. mouth, eyes, nose), or broken skin.
Body secretions (e.g. blood, vomit, stool, semen) contain viral particles after the infected
9
individual begins to show symptoms (Baron, McCormick, & Zubeir; Dowell et al.; Roels et al.).
High viral titers (numbers of virus particles) are believed to account for person-to–person
transmission. It may be that when a particular virus titer is reached virus exits the body through
breaks in the skin or sweat glands (Bausch et al.). This means transmission is unlikely until
symptoms appear.
The levels of infectious particles in symptomatic humans are believed to exceed 106 plaque
forming units (pfu)/mL serum (roughly one million virus particles in approximately one
tablespoon) thus accounting for transmission through direct contact. Transmission is also believed
to occur through eating an Ebola virus infected animal. Infected non-human primates organs
harbor 107 to 109pfu/gram tissue (greater than one million virions) so eating undercooked or
touching infected tissue (e.g. during food preparation) is believed to lead to infection. The
recommendation to thoroughly cook bush meat is due to the high virus loads in tissue (Leroy et
al.).
A media discussion regarding aerosol transmission of Ebola virus may have started because
of a misunderstanding over the definition of the word aerosol between experts and non-experts.
To experts aerosolized refers to a very small particle size that can potentially travel long distances
on air currents (Leffel & Reed), like the flu virus or tuberculosis. To date aerosolized transmission
of African Ebola virus has not been documented. To account for the large numbers of infected
animals in Reston VA however, aerosols generated by cleaning procedures are believed to have
contributed to the rapid spread of the virus (Feldmann).
Ebola virus is highly infectious; meaning infection with a small number of viral particles
can lead to death (Franz et al.). The virus is not highly transmissible, it is easily “killed” or
deactivated. This means direct contact with infectious virus is necessary for infection. Viruses
10
with low transmissibility have minimal risk of infection (through practices common in the U.S.)
thereby accounting for the minimal risk of infection for the majority of Americans. Most people
will not encounter infectious virus.
The route of infection predicts prognosis with injection directly into the blood (as might be
encountered in a hospital setting) being the most dangerous route of infection. A high dose
inoculum is associated with rapid disease progression and high case fatality rate (CFR). This is
because the more virus that is present the more cells that are infected. More infected cells produce
more virus that can repeat the infectious cycle thereby leading to rapid disease and death. The CRF
for the current outbreak has varied from 41% to 90%. Across the three countries the CFR averaged
about 71% (in September 2014) and was consistent across countries (Schieffelin et al.). With
supportive treatment mortality averaged 60% but CFR averaged 90% for people with no medical
care (Chan). The age of those infected has also been seen to influence prognosis in the 2014
outbreak with those under 24 years of age recovering from infection and those over 45 succumbing
(Schieffelin et al.).
Ebola does not live outside of an infected host for long (because of the delicate envelope)
so effective infection control methods, as seen in the U.S., limit transmission of the virus. If the
three countries in Africa with the highest transmission had clean water, plentiful disinfectant,
gloves, and sterilization equipment they would have been able to contain the spread of the virus to
a much greater extent (Leroy et al., 2004). Protecting health care providers from infection relies
11
on barrier-nursing methods. Personal protective equipment (PPE) consisting of gloves, plastic
gown and rubber boots as well as hat and face shield are recommended (see Figure 3).
Figure 3. CDC poster. Safe removal of Personal Protective Equipment (PPE).
Used with permission CDC.
The CDC said that improper adherence to the PPE protocol responsible for secondary
infection of HCP in both Spain and the U.S. (Leroy et al., 2004). The CDC later announced that
they had provided inadequate training in donning and doffing the PPE and also added additional
equipment.
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2.1.1.4 Clinical Signs and Pathogenesis
Infection and the subsequent disease had been referred to as Ebola hemorrhagic fever due to
bleeding seen in some patients later in infection. This name has lead to confusion because
hemorrhage in not seen in all cases so infection is now referred to as Ebola virus disease (EVD).
Ebola outbreaks provide important information regarding the pathology and pathogenicity
associated with infection because the high mortality, rapid of disease onset, and death prevent
clinical studies in humans. Due to the emergent circumstances however opportunities for research
are limited, data are not complete, and the situation does not allow for scientific rigor. Autopsies
are not generally performed due to the dangers inherent in handling infected tissue. Based on
outbreak data symptoms generally appear 8 – 12 days post exposure (minimum two, maximum
21) (Dowell et al.) and start with weakness and flu-like symptoms.
Symptoms include headache, fever, body ache, diarrhea, vomiting, and stomach pain.
These early symptoms are also associated with many infections such as malaria, cholera, and Lassa
fevers that are endemic to Guinea, Liberia, and Sierra Leone (Roll Back Malaria (RBM)
Partnership). As infection progresses impaired liver and kidney functions are reported. External
and internal bleeding may also occur and death follows shock (due to fluid loss) and multi-organ
failure. Hiccups are associated with hemorrhagic fevers in general (although why remains
unknown) and were a major diagnostic clue in the current outbreak (Stern).
Pathogenesis in humans remains an active field of study but laboratory studies in nonhuman primates demonstrate immune cells (monocytes, macrophages and dendritic cells) are
believed to be the preferred initial sites of virus replication (Geisbert et al., 2003). These cells
replicate and disseminate the virus throughout the body via trafficking to regional lymph nodes.
The virus infects resident immune cells and continued infection leads to premature cell death and
13
tissue destruction (Wauquier, Becquart, Padilla, Baize, & Leroy, 2010). Cell death and infection
leads to the release of soluble factors that recruit more target cells (thereby allowing for
amplification of the infection) and dysregulation of the immune response. Virus also traffics in
blood to the liver and spleen where the scenario is repeated. Tissue damage and virus replication
in tissues suggests direct virus killing of infected cells. Later in infection the virus is believed to
infect endothelial cells and hepatocytes (Zaki et al.). Infection of these cells coincides with immune
(Remien & Rabkin, 2001) dysfunction (e.g. cytokine storm) and a decrease in the production of
coagulation factors, due to liver necrosis. Liver failure (necrosis and decreased production of
coagulation factors) may increase hemorrhagic tendencies. Low blood pressure and the subsequent
shock are the most common causes of death in Ebola patients.
2.1.1.5 Survival
Surviving Ebola virus infection depends on receiving medical care as soon as possible after
symptoms emerge. Supportive therapy currently includes intravenous fluids, electrolytes and
transfusions (CDC). A person in good overall health before infection has the greatest chance of
full recovery. In the hardest hit countries endemic diseases (e.g. malaria is the number one cause
of death in both Liberia and Sierra Leone) weaken the immune system and decrease one’s ability
to fight infections in general. One recent study documented greater than five liter fluid loss/day
due to diarrhea (Chertow et al.). Leakage of intestinal bacteria can lead to secondary infections
that must be treated as they arise. People who do recover from Ebola infection generally suffer no
ill effects however a minority develops chronic inflammatory conditions that can continue through
the life of the individual.
A Ugandan newspaper interviewed survivors seven years after EVD and many people
reported headaches, body and joint pains, poor vision and sexual dysfunction (Ocowun). As to
14
why the residual effects are so long lasting is an active area of research (Firger). One study reported
that people avoided touching survivors long after they had recovered. Some survivors were not
allowed to return to their homes and some had family members and neighbors who were also
stigmatized because of the association with the survivor (Hewlett & Amola). One goal of risk
communication is to affect behavior change and this includes changing mind set. An increased
understanding of viral transmission and recovery can help to reduce stigmatization through
education. When the general public understands a survivor does not a risk to infection the stigma
associated with infection eliminated and the outrage factors are reduced.
15
3.0
OUTRAGE
Outrage, factors the public includes in their perception of a hazard to their life, things they value,
or their property are derived from many different things (Wolbarst, 2001)]. After the diagnosis of
Ebola virus in Texas 16% - 45% of Americans polled thought they (or a family member) would
become infected (Cohen, 2014; Thompson; WBUR). The polls did not inquire as to how people
thought they, or their family member, would be exposed to infectious virus. The public’s response,
seen as overreaction by experts, appears to be an inappropriate response to the risk. The public
focuses on factors that do not necessarily have anything to do with the risk (i.e. their probability
for contact with Ebola virus), rather they are absorbed by the feelings that the thought of the danger
provokes, their perception of the risk (see Table 1). Proximity to the danger can influence the
public calculations of risk (Sheppard, Janoske, & Liu, 2012). An increased perception of risk can
be influenced by factors that allow one to “feel” closer to the hazard. Real-time media coverage
and the ease of communication between distant family members tend to heighten the proximity of
risk (Barbara Reynolds, Hunter-Galdo, & Sokler). Close proximity also impacts ones feeling of
uncertainty and dread (Heath, Seshadri, & Lee), serving to increasing outrage. It falls to risk
communicators to encourage the public to react to hazards (e.g. wear protective equipment
properly) without overreacting (e.g. do not close schools unnecessarily). According to Sandman,
“outrage” are factors the experts often do not take into account when predicting then audiences
perception of risk [Sandman, EPA} and include emotional and personal factors.
16
Table 1. Risk Perception.
Risk Perception
High Outrage
Low Outrage
High Hazard
Low Hazard
Ebola infection in Guinea,
Liberia, Serra Leone
X-rays, drinking alcohol
(Generally underestimated)
Ebola diagnosis in Texas
(Generally overestimated)
Generally not
communicated
Modified from (Brucem, 2011)
3.1
OUTRAGE FACTORS
Outrage factors serve as a short cut to understanding. People use past experience, cultural
influences, feelings, and emotions to judge unfamiliar hazards (Finucane, Alhakami, Slovic, &
Johnson; Slovic; Zajonc). Over 20 outrage factors have been identified (P. Sandman) that influence
how acceptable the public finds a risk. Some of the factors related the public’s reaction infectious
agents are included below.
Understanding - Hazards that are relatively understood by science create less outrage than those
that are not.

Voluntariness – a hazard that is perceived to be involuntary can be perceived as having
greater risk than those perceived as voluntary.

Reversibility - Hazards with perceived irreversible unfavorable effects increase outrage.
Poliovirus infection when compared to measles virus infection is an example of
reversibility because one can cause permanent disfigurement (polio) while the other can
result in scaring (measles).
17

Familiarity – an unfamiliar hazard is seen as having a greater risk than a familiar hazard.
Hazards that are new and also invisible create high levels of outrage that further amplify
the perceived risk.

Catastrophic potential - Hazards that produce injuries and/or illness at one time, in one
place increase outrage over those that have scattered, random effects.

Dread - Hazards that evoke dread (anxiety, fear and terror) increase outrage. The public is
familiar with the cold viruses, the disease is referred to as the “common” cold, not knowing
whether the virus responsible was common or not. The public does not have the same level
of outrage when they learn that it is cold season, and people are infectious, and spread
disease when they do not have cold symptoms. We accept this yearly. The low level of
dread can also be influenced by the fact that infection with cold viruses does not generally
result in death.
Outrage factors alone impact how the public perceives risks but these factors also operate
within the individual’s social and cultural background (Eisenman, Cordasco, Asch, Golden, &
Glik; Phillips & Morrow; Sampson). Understanding how the public feels about a particular
hazard can enable public health leaders to counter factors influencing the perception of risk.
Taking all these elements into account relies to risk communication theory. Theories help inform
messaging when targeting specific audiences, thus potentiating a more effective exchange of
information.
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3.2
UNDERSTANDING OUTRAGE
People who are under stress, real or perceived, have a number of coping mechanisms that have to
be overcome or acknowledged to allow risk information to be processed and acted upon. Cognitive
and physical effects of stress can include impaired concentration and decision-making, and include
fatigue and hyperarousal (Barbara Reynolds, Hunter-Galdo, et al.). Media studies, psychology,
sociology, and anthropology help to inform the theories of risk communication and explain why
people react the way they do. Theories that guide risk communication attempt to explain why
matching the risk message to the audience’s culture and needs are more effective (MurrayJohnson, Witte, Thompson, Dorsey, & Miller; Phillips & Morrow) and clear, simple, and offer
solutions (Freimuth, Hilyard, Barge, & Sokler). There are several theories that are useful in helping
to explain why people react the way they do.
3.2.1 The Mental Noise Theory
This theory states that people under stress can have trouble understanding or remembering what
they hear (V. T. Covello et al.; Hyer, Covello, Organization., & Response). Research has
demonstrated that severe stress can cause a decrease in one’s ability to process information by as
much as 80%. The “primacy/recency” or “first/last” principal also states that people under stress
tend to remember what they hear first and last (Hyer et al., 2005; Tan et al.). Risk
communicators must overcome mental noise and design messages within the constraints caused
by the circumstances and understanding the audience’s cultural and social diversity.
Methods to overcome obstacles caused by mental noise include: limiting the number of
words (27 words maximum), keeping key points to a maximum of three, and targeting the language
19
used to an adult with a 6th grade education. “Stop, drop, roll”, the instructions for extinguishing a
fire in one’s clothing, is an example of messaging to overcome mental noise. For the most impact
the message or instructions one wants to convey should be presented first and repeated last. Using
narratives and analogies can result in increasing message recall by as much a 50% (Hyer et al.).
Another approach is to use the “Tell me, Tell me more, and Tell me again model” in which the
three point message is delivered, supporting information is shared, and the three point message is
repeated, the “rule of three” (Lin, Petersen, & National Risk Management Research, 2007).
Messages that address fear also decrease interference caused by metal noise. This model is based
on the premise that in repeating the message, both through various channels and the repetition
itself, any mental noise interfering with comprehensions will be minimized.
3.2.2 Trust Determination Theory
This theory (Glik) is exemplified by a quote attributed to Theodore Roosevelt; “people don't care
how much you know until they know how much you care.” People under stress tend to distrust
authority but a high level of trust positively influences the public’s perception of risk. The goals
of risk communication can only be achieved after trust has been established. To demonstrate
trustworthiness public health officials must convey empathy, competence/expertise, honesty, a
caring attitude, and a commitment to the public. Research demonstrated that caring and empathy
were the two most important factors in shaping the public’s perception of trust and the a major
factor in gaining the public’s trust in high stress situations (Hyer et al.).
Trust must be earned over time so an organization must be seen as transparent in their
goals, truthful, and associated with other credible organizations (Fullerton, Ursano, Norwood, &
Holloway). If a question does not have an answer that fact itself must be clearly stated (e.g. “the
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answer to that question is currently unknown…”). The organization/spokesperson must be
empathetic to the feelings created in the audience by the lack of important information. The
organization/spokesperson does not have to have all of the answers but must be truthful in
responding. The interactive nature of risk communication is evident here because identifying
issues important to the public is a key factor in both building and maintaining trust (Earle).
3.2.3 Social Amplification of Risk Framework
Revealed in 1988 (Kasperson et al.), social amplification of risk is an integrative framework that
is able to incorporate research from a wide range of disciplines (e.g. cultural, psychological, risk
perception, and media) to describe how individuals interpret risk messages and perceive risk. The
framework links risk perception and risk behavior with the sociological, cultural, and
psychological standpoints. The framework explains how a hazard the experts are relatively
unconcerned about can be judged as high concern by the public (risk amplification, and,
conversely, how a hazard the experts are concerned about may be assess as low concern by the
public (risk attenuation). The framework assumes a “risk event” (actual or not) will be ignored or
remain local unless the event is observed and communicated to others. The risk and the risk event
are conveyed through “risk signals” (signs, symbols, images) that are also influenced by processes
(cultural, social, psychological, or institutional). As a risk signal filters through social and
individual “amplification stations” (generation, receipt, interpretation and passing on the signal)
the way one experiences the risk event is influenced. Within this framework risk is an interaction
of the physical harm, and the cultural and social processes that shape ones interpretation of the risk
event. Additionally “ripples” (secondary and tertiary events) are created that can reach beyond the
initiating event. As the ripples expand beyond the first victims, their families, institutions,
21
governments, and countries can be affected. This theory exemplifies the two-way process of risk
communication. It takes into account the public speaking with one another, with officials, with
institutions, listening to media (e.g. television, internet), and responding to messages (e.g. blogs,
and Facebook pages).
3.2.4 Crisis and Emergency Risk Communication (CERC) theory
CERC was developed for the CDC (Barbara Reynolds, Hunter-Galdo, et al., 2002) to aid their
public health professionals in communicating accurate and timely health information in a
reassuring manner during health crises or emergency situation. The need for CERC was based on
the expanded role of public health officials from an ancillary position to that seen as more of a first
responder capacity. Historically officials primarily identified risks and communicated behavior
change so the public could limit damage from the risk. Currently the role also includes matching
the values, background, culture and experience of audiences to increase their understanding of the
event, and increase their confidence and ability to act in the appropriate and desired manner.
Understanding that a crisis requires different management techniques than everyday events
the method is divided into different phases, that mimic the phases of an evolving crisis: Precrisis,
Initial, Maintenance, Resolution, Evaluation. Each stage consists of tasks tailored to allow for
quick responses, anticipation of problems, and the relationship between the task and the outcome.
Additionally each phase informs the next, thereby maintaining homogeneity, but the entire process
is interactive thus allowing for rapid adjustment as is deemed necessary
Tasks during the precrisis phase include forming alliances, and developing and testing
messaging. Communication focuses on warnings and recommendations for preparation. The
method stipulates that the majority of planning takes place during the precrisis phase as there is
22
not sufficient time after an initial event to develop and test the needed messages. Considerable
research describing what risks can be anticipated, what questions will need to be answered, who
will need to know what, and how best to express this information has been performed (Wray,
Kreuter, Jacobsen, Clements, & Evans, 2004). The initial phase of a crisis is when the public needs
to be informed of their risk and how to limit best protect themselves and that which they value.
Statements for this phase should be easy to understand, delivered with empathy and be reassuring.
A commitment to continued communication should also be conveyed.
During the maintenance phase feedback regarding what further education is needed should
be gathered. A more in-depth understanding of the risks and emergency recommendation should
be provided to engender support for recommendation and empower the public to make informed
decisions. The resolution phase focuses on encouraging the public to adopt policies aimed at
reducing a repeat future event and to improve response should one occur. This phase also involves
an unbiased assessment of problems, missteps and successes. Finally, the evaluation phase is
dedicated to improving performance based on past lessons and new understandings of risk that
were brought to light.
Theories that help to explain why people react the way they do help to inform risk
communication. This understanding allows messaging to be crafted in a way to allow for the
maximum probability of overcoming barriers to communication of specific populations. Risk
communication for Ebola virus in the U.S. focused on general education regarding transmission
of the virus targeted toward a general audience.
23
4.0
COUNTERING PERCEPTIONS OF RISK
To reiterate, the goal of risk communication is to give the public the information they need to
protect what they value and to keep themselves and their families healthy and alive, to enable an
interactive dialogue, and to gain input and support for programs and policies. Effective
communication depends on overcoming barriers to communication and is influenced by who is
delivering the message. Spokespeople influence the public through both the sincerity with which
they deliver the message as well as the message itself (Barbara Reynolds).
4.1
SPOKESPERSON
The spokesperson for an agency becomes the agency in the public’s mind. The CERC model
suggests spokespeople act as if they themselves were the agency they represent (B. Reynolds &
Seeger). This model recommends spokespeople embody the identity of the agency, that
spokespeople act as the best qualities of the agency itself. The CDC exists to keep people safe and
healthy. In embodying this vision the spokesperson would express a sincere desire to help, actively
listen, and freely share information to enable the public to make informed decisions.
Research has demonstrated a number of factors audiences require of the spokesperson for
the message to be understood and acted upon (Barbara Reynolds; Barbara Reynolds, HunterGaldo, et al.). The CDC has found that a good spokesperson displays empathy, humility,
truthfulness, a willingness to admit what is not known, and confidence without arrogance (Peters,
24
Covello, & McCallum). Numerous frameworks recommend these traits so this description is not
limited to the CDC (Hyer et al.; Janoske).
Research has shown that expressing empathy, either in written form or in a spoken
message, allows the message a greater chance of being “received and acted upon” (Barbara
Reynolds, Hunter-Galdo, et al., 2002, p. 38). The public will be listening for an acknowledgement
of their feelings. The spokesperson does not have to be frightened to understand that people are
frightened and acknowledge the feeling. An expression of empathy must come within the first 30
seconds (Steib) or the public loses trust in the spokesperson and the agency they represent.
Factors the influence trust change with the public’s perception of risk (Sjöberg). When
the public perceives an event (e.g. infectious disease, natural disaster) as low outrage their
perception of trust is based on the spokesperson’s expertise (education and training). All other
factors that go into the public’s perception of trust (empathy, honesty, commitment) together
represent approximately 17%. When the event causes high outrage 50% (Peters et al.) of the trust
the public feels towards the spokesperson is based on empathy expressed within the first 30
seconds.
To give the spokesperson credibility the “Crisis and Emergency Risk Communication: by
Leaders for Leaders” (Barbara Reynolds) dictates six elements be present in the first message
regarding a new risk: expression of empathy, confirmation of facts, admission of what is currently
unknown, detailing the steps necessary to get answers to unknowns, a statement of commitment,
where additional information can be found (e.g. website or hotline), and the frequency of updates.
The CDC follows this formula because they found that the public wants specific information in a
crisis:
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1) protect themselves and their families.
2) ability to make informed decisions with the available information.
3) active participants in both the response and the recovery.
4) remain informed regarding finances.
5) return to “normal.”
The answers the public wants mirror the goals of the spokesperson, e.g. minimal illness or injury,
the ability to execute recovery plans with little resistance, and no waste of either funds or resources.
The CDC evaluated past communication efforts during emergency responses and found
that a number of factors influence the credibility of the spokesperson as well as how the message
is judged (Barbara Reynolds, Hunter-Galdo, et al., 2002). This can influence the success of the
organization in managing the crisis (Barbara Reynolds, Hunter-Galdo, et al.). Having a solid
communication plan, being the first to provide information, expressing empathy, demonstrating
competence and remaining open and honest are all key to successful efforts. Solid plans ensure
that necessary steps will be completed and that pertinent information will be available and accurate
when it is needed. Being the first to provide information gives the organization and the
spokesperson credibility because the public sees an organization that is well prepared and able to
respond to the crisis. Being first with information is recommended because people are
uncomfortable when they are uncertain (Barbara Reynolds, 2002), they want answers even if the
answer is that there is no answer at present. Being first also allows all other information to be
compared to that which you provide since the public tends to weigh subsequent messages against
the first information they hear (see Mental Noise Theory).
The competency of the spokesperson can often be expressed in a sentence by providing
their title. The public assumes the director of the CDC is competent, that s/he has the education
26
and training to direct the Centers or s/he would not have been selected for the position (Barbara
Reynolds, 2002, p. 11). Successful communication also depends on maintaining an open and
honest dialogue. Research has shown that the public believes their government withholds
information (Barbara Reynolds, 2002, p. 11) so all information, good and bad, needs to be shared
to increase the public’s perception of credibility in the agency and the spokesperson. Providing the
public with what is known also alleviates anxiety over fear of the unknown. People can receive
bad news and prepare for bad outcomes only if they are made aware there can be negative
consequences. Withholding information is seen to imply arrogance or guilt. Legitimate reasons
exist for holding back information and people understand this (e.g. legality, or it is not your
information to share) but the public must be told why the information is not forthcoming to
maintain credibility.
Evaluating past performance has also revealed that factors that can negatively influence
efforts include: mixed messages, late information, perceived paternalistic attitudes, confusion or
power struggles, and not countering erroneous information immediately (Barbara Reynolds).
Mixed messages leave the audience confused. People do not know what is expected of them so
they can respond by doing nothing or worse, lose trust and therefore stop paying attention to any
message provided. When the public seeks information they will find it, they may find erroneous
information on a website and as mentioned above, the first information they hear will be what they
judge subsequent information against. This can undermine educational efforts, as countering
erroneous information is very difficult. Paternalistic attitudes give the impression that the agency
does not give the public credit for being able to reach their own conclusions, provided they have
the information they need to do so. Give the public the information that allowed for the conclusion
presented, this allows the public to reason through the logic themselves. The CERC handbook
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states “Treat the public like intelligent adults and they will act like intelligent adults” (Barbara
Reynolds, Hunter-Galdo, et al., 2002, p. 7) The recommendation to use language easily understood
by 6th graders (see Mental Noise Theory) cuts through barriers to communication by providing the
listener with easily understood goals and/or objectives. Organizations collaborating toward the
public good (e.g. CDC, WHO) but who are not seen to be working together can give the impression
that there is confusion as to the correct response, undermining trust in both the organizations and
in their recommendations. Additionally, if rumors are not countered quickly the credibility of the
spokesperson and the credibility of the organization will suffer. Countering every rumor would
waste of time but rumors that are “trending” need to be addressed so false information is not
allowed to spread (Barbara Reynolds, Hunter-Galdo, et al., 2002). The above “rules” demonstrate
that the selection of spokesperson, their responsibilities, and areas the communication plan needs
to address are not insignificant.
Sandman notes that experts tend to make comparisons to change the public’s perception of
a hazard (Barbara Reynolds, Hunter-Galdo, et al., 2002; P. Sandman, p. 22) Since experts and the
public calculate risk differently comparisons the experts judge as valid (high hazard compared to
low hazard, e.g. death from influenza infection vs. death from Ebola infection) are unacceptable
to the public if the outrage factors do not match. Ebola infection provokes high outrage (exotic,
novel, unfamiliar) in the public unlike the flu, so the comparison is not seen as valid (Barbara
Reynolds, Hunter-Galdo, et al.). CDC recommends instead bracketing the risk if need be (e.g.
bigger than X, smaller than Y) to provide a comparison.
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4.2
SPOKEN WORD
The fact that the Ebola virus itself was present in the U.S., i.e. the proximity of the virus to an
American citizen was known to increase dramatically after September 30th, meant a number of
different outrage factors influenced the public’s perception of risk. Countering these factors
required an understanding of why particular factors were evoked.
The U.S. public likely understood that the science regarding the virus was limited. This
was because they knew there was no standard treatment or vaccine; two things the public knows
are common for viruses that are well studied and understood. An example is the influenza virus;
there is an effective vaccine, which changes yearly, and a standard treatment protocol (even if the
treatment is to allow the virus to “run its course”). Influenza virus infection is responsible for
approximately 53,000 deaths yearly in the U.S. (Centers for Disease Control and Prevention) but
only 34% of those aged 18 - 64 get the vaccinated (Flannery et al.). This illustrates a high hazard
to experts but the public has a low sense of outrage, therefore perceives as low personal risk and
takes no action. With Ebola virus in the U.S. the potential exposure to the virus was no longer
perceived as voluntary. Someone visiting the U.S. brought the disease with him or her. Exposure
to the virus did not require visiting a location with active infection or the reservoir species to
become infected. In terms of the reversibility of the hazard this factor is highly relevant when
dealing with an infectious disease such as Ebola. This virus has the potential to quickly kill those
who become infected and as yet, death is not reversible. Again, influenza virus infection kills
approximately 53,000 Americans yearly but is not met with as great an outrage as the Ebola
diagnosis was. People are familiar with “the flu” (but not familiar with the fatality statistic) so the
outrage is not as great. Alternatively if 53,000 influenza-infected individuals were killed
simultaneously the public’s feelings of outrage due to the catastrophic potential of infection would
29
cause high outrage and dread. The factors influencing American’s reaction to Ebola virus were not
unfounded; it is not unreasonable to be frightened of something that can kill you. The reactions
are natural “fight or flight” reactions that keep people safe and alive. Experts need to present the
facts regarding the hazard of infection (virtually non-existent to the vast majority of Americans)
while acknowledging and addressing the factors influencing people’s reaction. The CDC was
responsible for informing the public about their exposure risk and quelling fears.
The CDC understood that the Ebola outbreak occurring in Africa was completely
unfamiliar to the American public so the director of the CDC, Dr. Thomas Frieden, was selected
as spokesperson. Dr. Frieden’s title alone contributed to his credibility to a segment of the
population. Before the diagnosis of Ebola virus in the United States, and before the outbreak was
declared an international health threat, the CDC held press briefings to update the public about
the Ebola virus outbreak. On July 31st Dr. Frieden introduced himself and said: “Hi. This is Dr.
Frieden. Let me start with the big picture. Then I will go through considerable detail about what's
happening with the Ebola outbreak in West Africa. It is complex…First, by way of background;
Ebola virus disease is very frightening. It is frankly a dreadful and merciless virus. The current
outbreak is bad. It's the biggest, most complex and the first time it's been present in this region of
the world which means that response systems and community understanding of the disease is not
what it is elsewhere. It's been deadly and far too many lives have already been lost…” (CDC).
Dr. Frieden demonstrated empathy by admitting that infection was frightening and that too many
people had died. This was delivered during the critical first 30 seconds when the public was
deciding whether or not to trust him and the agency he represented. The outrage factor of dread
was addressed by admitting that the virus was deadly, merciless, and that the outbreak was bad,
big, and not yet controlled. This briefing set the stage for future communication by introducing
30
Frieden as empathetic and trustworthy, and by communicating that the CDC was the first source
for credible information.
On August 3rd, 2014 Dr. Frieden, in speaking about the chance of Ebola virus in the U.S.
said that an infected individual could enter the country and if not properly diagnosed the infection
could spread (Frieden). This was an open and honest acknowledgement that Ebola might enter the
U.S. In the parlance of crisis and risk communication this was “anticipatory guidance”. This type
of message is used to warn the audience that something bad may happen. Anticipatory guidance
allows the audience to prepare, both their reaction to, and for the event. This preparation enables
people to cope with the event if/when it occurs.
In the September 30th press briefing announcing the diagnosis in the U.S. (CDC) Frieden
said: “Good afternoon, everybody. Thanks for joining us. As you have been hearing us, Ebola is a
serious disease. It's only spread by direct contact with someone who's sick with the virus. It's only
spread through body fluids… It's a severe disease which has a high case fatality rate, even with the
best of care…Today, we are providing the information that an individual traveling from Liberia
has been diagnosed with Ebola in the United States… So what does this mean? The next steps are
basically threefold.” In this statement an expression of empathy was neglected. A segment of the
audience may not have heard any earlier press briefings therefore his entire message may have
been disregarded because of the lack of empathy. The outrage factors of proximity and novelty
were addressed. Stating that direct contact with someone who is sick is needed to transmit the virus
can aid in increasing tolerability by educating the public that without contact with infectious virus
transmission will not occur. Announcing that the virus, heretofore confined to Africa, was in Texas
and using the “rule of three” when stating what has to happen to become infected and what the
responsible parties were doing to halt transmission also countered mental noise.
31
At the beginning of the October 2nd telebriefing (CDC) again regarding the first diagnosis
of Ebola in the U.S. Dr. Frieden said in part “…our approach is always to provide all the
information that's available as soon as we can make it available. We know that there are a lot of
questions that people wish they had answers to, and we may not have those answers yet. What we
can do is tell you what we know and what we're doing to find out more about the things that we're
all interested in…” Frieden was countering Mental Noise by repeating his central theme that all
questions may not yet have answers but the CDC will not hold back information. His message was
also designed to conveyed trust and credibility by admitting that all of the desired information is
not yet known. By following through with the pledge to keep people informed the CDC would
also demonstrate its trustworthiness.
When addressing the fear of contracting Ebola Frieden (October 2nd) said (CDC) “…can
we make the risk zero… the bottom line here is, the plain truth. We can't make the risk zero until
the outbreak is controlled in West Africa. What we can do is minimize that risk…by working to
ensure that there are no more individuals exposed than have already been exposed….But until the
outbreak is controlled in West Africa, we won't be able to get to that zero risk.” Again, he repeated
the central theme, the impossibility of zero risk, while also continuing to educate that the real threat
is in the continuing transmission of Ebola virus in Africa. By reiterating that the outbreak in Africa
had to be controlled he was also advocating for support for policies in Africa.
One week after the initial announcement of the Ebola diagnosis in the U.S. (CDC) Dr.
Frieden said “Good morning, everyone…Today is one week since the first party with Ebola in the
United States was diagnosed, and one week into a situation, people begin to look back and think
about it, think about what went right, what went wrong, what are the implications for the future?
… It's a virus that doesn't spread through the air, and that we do know how to control. We do know
32
how to stop it.” Frieden addressed the outrage factor of proximity by repeating that Ebola virus
was in the U.S., and by saying that as yet there was no transmission to others outside of the one
Ebola infected individual (no secondary transmission). No secondary transmission of the virus also
increases tolerability and decreases dread by demonstrating that the presence of the virus does not
guarantee infection. This statement was made before to two health care providers in Texas became
infected.
In terms of the CERC model messaging for different phase, one message during the
precrisis phase was delivered in the July 31st briefing: “But we know what to do. In addition, as
we always do, we are taking steps to make sure that Americans are safe here. So we work with
hospitals and other groups to make sure if there is a traveler with Ebola in the U.S., we would be
able to contain that”. This message provides the anticipatory guidance and gives assurance that the
agency knows how to limit virus transmission. During the initial phase Dr. Frieden said “Ebola is
a virus that is easy to kill by washing your hands. It’s easy to stop by using gloves and barrier
precautions. The issue is not that Ebola is highly infectious, the issue is that the stakes are so high.”
This statement helps to counters Mental Noise through repetition of the main point. The concluding
sentence is not easily understood so all audience members may not comprehend the message to
the same extend. “We’re working very intensively on the screening process as the president said.
Both in places of origin and on arrival to the U.S., and we're looking at that entire process to see
what more can be done…Screening at airports, of course, would not have found fever in the patient
in Dallas because he did not have fever for four or five days after he arrived, but we'll look at all
of the options. We're not, today, providing the step that we plan to take, but I can assure you we
will be taking additional steps and will be making those public in the coming days once we work
33
out the details.” This statement reported that lessons learned were being used to evaluate and reevaluate protocols.
The CERC framework dictates that spokespeople be rotated out during a crisis situation.
The CDC did not have a Surgeon General from August through December of 2014 so there was
no one with the same credibility as Dr. Frieden to take his place. This could have led to fatigue
and caused some misstatements on his part. CERC framework states that any error should
immediately be acknowledged and corrected but this was not always done. Why mistakes were
not immediately corrected is currently unknown but as the director of the CDC Dr. Frieden had to
direct the CDC as well as respond to demands for Ebola updates.
The Social Amplification of Risk Framework explains the heightened reaction by the
American public to the diagnosis of Ebola, at least in part. The public’s interest in Ebola virus was
not high when Ebola was in Africa. This was demonstrated by the number of times the term
“Ebola” (in any context) was searched for using “Google”. A “Google trends” graph of the relative
number of searches from September to December shows a large spike after the diagnosis in Texas
(see Figure 5). After the secondary exposures and recoveries the interest dropped precipitously.
34
A. Represents November 10, 2014. B. Represents October 1, 2014 (Google Trends).
Figure 4. Previous 90 day Google Trend graph of Ebola searches.
The October decrease in the number of “Ebola” searches also represents a missed
opportunity to influence the public’s response to health events in other parts of the world. The
American public did not have a large interest in Ebola virus before it came to the U.S. nor was
there a large interest after it was eradicated. If the CDC had been able to increase the public’s
outrage to the Ebola outbreak in Africa that could have furthered the understanding that a health
threat anywhere on the globe is a health threat to the U.S. An infectious agent (for example)
originating anywhere can have effects locally. Interestingly, in terms of Google searches for both
the world and the U.S., Robin Williams (actor, comedian) topped the Google search results for the
year with Ebola ranking third (Google Trends, 2014).
It is easy to identify missed opportunities after an event has occurred. This is one reason
evaluation needs to be an ongoing component of any public health program. As to the Ebola
diagnosis in the U.S. numerous examples of both good and bad messaging can be found. This
demonstrates that having a solid communication plan, deciding what information the agency
35
needs/wants to provide to stakeholders, can be effectively communicated using risk
communication techniques.
36
5.0
CONCLUSION
Risk communication in the United States grew from the necessity of explaining the dangers the
public faced from environmental and occupational accidents and the subsequent law protecting the
public’s right to know (see http://www.epa.gov/agriculture/lcra.html for complete information
regarding the act). Risk communication methods evolved from a stark presentation of facts to
include matching the values, background, culture and experience of the intended audience
(Fischhoff, Bostron, & Quadrel, 1993). Research demonstrated this increases the audience’s ability
to understand the event, and increases their confidence and ability to act in the appropriate and
desired manner. Public health leaders of infectious disease can craft effective communication
strategies provided they understand barriers to comprehension exist and have methods to overcome
them. The goals of effective risk communication include: establishing credibility, increasing
knowledge, easing anxiety, guiding attitudes and behaviors, encouraging cooperation, and
promoting an interactive dialogue regarding a health risk. As the diagnosis of Ebola virus in Texas
demonstrated the task is not trivial.
The luxury of tailoring messages to target audiences was not possible because of the urgent
demand for information. This demand meant all briefings were relayed in real-time through
numerous communication channels (e.g. television, radio, print, twitter). Audiences could access
the information at will thereby allowing for a misinterpretation of personal risk because of the
generality of information. This also represented another missed opportunity; the government could
have anticipated this and had tested risk communication messages ready.
Getting the apathetic to act and reassuring the overanxious are both part of risk
communication and require two very different messages. Neither of the tasks is easily
37
accomplished, as the reaction to the diagnosis to Ebola in the U.S. demonstrated. Some experts
had been anticipating the entry of the virus for almost 40 years (since it was first discovered) while
the thought had never entered the minds of others. Health providers and the government may have
met the diagnosis with under-reaction. The fact that two health care providers became infected
themselves demonstrates this. Trained health professionals did not follow protocol, or they did not
think they could be infected (Heide, 2004), or they did not have time to take the hazard seriously,
or the recommendations provided by the government were inadequate, or the government did not
stress the importance of following a proscribed protocol (Janssen, Tardif, Landry, & Warner,
2006). Any, or a combination of these factors could have contributed to the infection of the helath
care workers and demonstrate the difficulty inherent to communicating risk to a diverse group of
people.
Risk communication is a relatively new science so advances in the techniques and tools to
will be forthcoming. This essay did not cover all of the topics that constitute risk communication
but there are a number of resources available (Abraham; Glik; Hyer et al.; Infanti et al.; Jardine et
al.; Renn, 1998). This skill will be in increasing demand both in the public health infectious disease
field in general and as one moves higher in positions of leadership, as was amply demonstrated by
Thomas Frieden.
Theories that inform crisis and risk communication provide insight into factors that make
people react the way they do. Understanding what triggers a reaction enables communication
messages to be designed to overcome or diminish the impact of these factors. The goal of risk
communication is to provide the public with information they can use to make informed
decisions about behavior change (that may be mindset change) they can adopt to protect
themselves and their families from danger. Public health leaders can gain cooperation and
38
approval from the public for policy changes and practices with effective risk communication.
There are no guarantees that risk communication will have the desired effect but studies have
demonstrated that a lack of communication will have a negative effect (Ng & Hamby). The
lessons learned from the Ebola “crisis” in the United States will inform future crisis and risk
communication.
39
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