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

ii

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 MicrobiologyGraduate School of Public HealthUniversity of Pittsburgh

Essay Reader:Elizabeth Felter, DrPH ______________________________________Visiting Associate Professor Behavioral and Community Health SciencesGraduate School of Public HealthUniversity of Pittsburgh

iii

Copyright © by Rachel Taber

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

iv

Lawrence Kingsley, DrPH

CRISIS AND RISK COMMUNICATION:

PUBLIC HEALTH ISSUES OF HAZARD, OUTRAGE, AND EBOLA VIRUS

Rachel Taber, MPH

University of Pittsburgh, 2014

represents the experts and must be perceived as empathetic, honest, and knowledgeable to gain

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

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

4.0 COUNTERING PERCEPTIONS OF RISK............................................................24

vi

4.1 SPOKESPERSON..............................................................................................24

4.2 SPOKEN WORD................................................................................................29

5.0 CONCLUSION...........................................................................................................37

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 19 th, 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

1

infection. Suddenly, with Ebola virus in the U.S. Americans thought they too could become

infected.

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

2

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

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

3

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.

4

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

5

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.

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

6

epidemic, thereby hindering containment efforts. The World Health Organization (WHO)

declared an international health emergency on August 8th, 2014.

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.

7

(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 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,

8

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

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).

9

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.

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

10

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-

to-person (person-to-animal) contact or from contact with contaminated surfaces (e.g. clothing,

non-sterilized 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

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

11

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

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

12

to a much greater extent (Leroy et al., 2004). Protecting health care providers from infection

relies 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

13

they had provided inadequate training in donning and doffing the PPE and also added additional

equipment.

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 non-

human 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

14

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

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.

15

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

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.

16

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

17

account when predicting then audiences perception of risk [Sandman, EPA} and include

emotional and personal factors.

Table 1. Risk Perception.

Risk Perception High Hazard Low Hazard

High Outrage Ebola infection in Guinea, Liberia, Serra Leone

Ebola diagnosis in Texas(Generally overestimated)

Low Outrage X-rays, drinking alcohol(Generally underestimated)

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

18

reversibility because one can cause permanent disfigurement (polio) while the other can

result in scaring (measles).

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.

19

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

(Murray-Johnson, 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

20

language 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, &

21

Holloway). If a question does not have an answer that fact itself must be clearly stated (e.g. “the

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

22

that can reach beyond the initiating event. As the ripples expand beyond the first victims, their

families, institutions, 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

23

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

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.

24

25

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, Hunter-

Galdo, et al.). The CDC has found that a good spokesperson displays empathy, humility,

26

truthfulness, a willingness to admit what is not known, and confidence without arrogance (Peters,

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

27

frequency of updates. The CDC follows this formula because they found that the public wants

specific information in a crisis:

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

28

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

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

29

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 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

30

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.

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 30 th, 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

31

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 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

32

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

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

33

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.

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.

34

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 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

35

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 out the details.” This statement reported that lessons learned were being used

to evaluate and re-evaluate 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.

36

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

37

needs/wants to provide to stakeholders, can be effectively communicated using risk

communication techniques.

38

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

39

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

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

40

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

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.

41

BIBLIOGRAPHY

Abraham, T. (2011). Lessons from the pandemic: the need for new tools for risk and outbreak communication. Emerging Health Threats Journal, 4, 1-4. doi: 10.3402/ehtj.v4i0.7160

Aleksandrowicz, P., Marzi, A., Biedenkopf, N., Beimforde, N., Becker, S., Hoenen, T., . . . Schnittler, H. J. (2011). Ebola virus enters host cells by macropinocytosis and clathrin-mediated endocytosis. Journal of Infectious Diseases, 204 Suppl 3, S957-967. doi: 10.1093/infdis/jir326

Baron, R. C., McCormick, J. B., & Zubeir, O. A. (1983). Ebola virus disease in southern Sudan: hospital dissemination and intrafamilial spread. Bull World Health Organ, 61(6), 997-1003.

Bausch, D. G., Towner, J. S., Dowell, S. F., Kaducu, F., Lukwiya, M., Sanchez, A., . . . Rollin, P. E. (2007). Assessment of the risk of Ebola virus transmission from bodily fluids and fomites. Journal of Infectious Diseases, 196 Suppl 2, S142-147. doi: 10.1086/520545

Brucem. (2011). Outrage Management. Retrieved from http://xray-delta.com/2011/10/31/outrage-management/

Carette, J. E., Raaben, M., Wong, A. C., Herbert, A. S., Obernosterer, G., Mulherkar, N., . . . Brummelkamp, T. R. (2011). Ebola virus entry requires the cholesterol transporter Niemann-Pick C1. Nature, 477(7364), 340-343. doi: 10.1038/nature10348

CDC. (2014a). CDC Press Conference: CDC Confirms First Ebola Case Diagnosed in the United States | CDC Online Newsroom | CDC. Retrieved September 30, 2014, 2014, from http://www.cdc.gov/media/releases/2014/t0930-ebola-confirmed-case.html

CDC. (2014b). CDC Telebriefing on Ebola outbreak in West Africa [Press release]. Retrieved from http://www.cdc.gov/media/releases/2014/t0728-ebola.html

CDC. (2014c). CDC Telebriefing: CDC update on first Ebola case diagnosed in the United States, 10-02-2014. Retrieved October, 14, 2014, 2014, from http://www.cdc.gov/media/releases/2014/t1002-ebola-in-us-update.html

CDC. (2014d). CDC Telebriefing: CDC update on first Ebola case diagnosed in the United States, 10-07-2014. CDC online newsroom. Retrieved October 14, 2014, 2014, from http://www.cdc.gov/media/releases/2014/t1007-ebola-confirmed-case.html

42

CDC. (2014e). Ebola (Ebola Virus Disease) Treatment. Retrieved August 18, 2014, 2014, from http://www.cdc.gov/vhf/ebola/treatment/

CDC. (2014f). Interim Guidance for Environmental Infection Control in Hospitals for Ebola Virus | Ebola Hemorrhagic Fever | CDC.

Centers for Disease Control and Prevention. (2014). Deaths and Mortality. FastStats. Retrieved September 29, 2014, from http://www.cdc.gov/nchs/fastats/deaths.htm

Chan, M. (2014). Ebola virus disease in West Africa--no early end to the outbreak. N Engl J Med, 371(13), 1183-1185. doi: 10.1056/NEJMp1409859

Chertow, D. S., Kleine, C., Edwards, J. K., Scaini, R., Giuliani, R., & Sprecher, A. (2014). Ebola virus disease in West Africa—clinical manifestations and management. New England Journal of Medicine, 371(22), 2054-2057.

Cohen, R. (2014). A quarter of Americans think they or their families will get ebola. Mother Jones. Retrieved from Environmental, Health, International website: http://www.motherjones.com/environment/2014/08/ebola-debunked-0

Covello, V. T., & Allen, F. W. (1994). Seven cardinal rules of risk communication: US Environmental Protection Agency.

Covello, V. T., Peters, R. G., Wojtecki, J. G., & Hyde, R. C. (2001). Risk communication, the West Nile virus epidemic, and bioterrorism: responding to the communication challenges posed by the intentional or unintentional release of a pathogen in an urban setting. J Urban Health, 78(2), 382-391. doi: Doi 10.1093/Jurban/78.2.382

Dowell, S. F., Mukunu, R., Ksiazek, T. G., Khan, A. S., Rollin, P. E., & Peters, C. J. (1999). Transmission of Ebola hemorrhagic fever: a study of risk factors in family members, Kikwit, Democratic Republic of the Congo, 1995. Commission de Lutte contre les Epidemies a Kikwit. Journal of Infectious Diseases, 179 Suppl 1, S87-91. doi: 10.1086/514284

Earle, T. C. (2004). Thinking aloud about trust: A protocol analysis of trust in risk management. Risk Analysis, 24(1), 169-183.

Eisenman, D. P., Cordasco, K. M., Asch, S., Golden, J. F., & Glik, D. (2007). Disaster planning and risk communication with vulnerable communities: lessons from Hurricane Katrina. Am J Public Health, 97 Suppl 1, S109-115. doi: 10.2105/AJPH.2005.084335

Feldmann, H., Sanchez A. and Thomas W. Geisbert. (2013). Filoviridae: Marburg and Ebola viruses Fields Virology (6th ed.): Lippincott Williams & Wilkins.

Finucane, M. L., Alhakami, A., Slovic, P., & Johnson, S. M. (2000). The affect heuristic in judgments of risks and benefits. Journal of behavioral decision making, 13(1), 1-17.

43

Firger, J. (2014). Surviving Eboal: for those who live through it, what lies ahead? Retrieved September, 13, 2014, 2014, from http://www.cbsnews.com/news/surviving-ebola-for-those-who-live-through-it-what-lies-ahead/

Fischhoff, B., Bostron, A., & Quadrel, M. J. (1993). Risk perception and communication. Annual Review of Public Health, 14.

Flannery, B., Thaker, S. N., Clippard, J., Monto, A. S., Ohmit, S. E., Zimmerman, R. K., . . . Jackson, L. A. (2014). Interim estimates of 2013-14 seasonal influenza vaccine effectiveness-United States, february 2014. MMWR Morb Mortal Wkly Rep, 63(7), 137-142.

Franz, D. R., Jahrling, P. B., Friedlander, A. M., McClain, D. J., Hoover, D. L., Bryne, W. R., . . . Eitzen, E. M., Jr. (1997). Clinical recognition and management of patients exposed to biological warfare agents. JAMA, 278(5), 399-411.

Freimuth, V. S., Hilyard, K. M., Barge, J. K., & Sokler, L. A. (2008). Action, not talk: a simulation of risk communication during the first hours of a pandemic. Health Promot Pract, 9(4 Suppl), 35S-44S. doi: 10.1177/1524839908322111

Frieden, T. (2014) Transcripts, August 3, 2014/Interviewer: N. O'Donnell. Face the Nation, CBS News.

Fullerton, C. S., Ursano, R. J., Norwood, A. E., & Holloway, H. H. (2003). Trauma, terrorism, and disaster. Terrorism and disaster. Individual and community mental health interventions, 1-20.

Gatherer, D. (2014). The 2014 Ebola virus disease outbreak in West Africa. J Gen Virol, 95(Pt 8), 1619-1624. doi: 10.1099/vir.0.067199-0

Geisbert, T. W., Hensley, L. E., Larsen, T., Young, H. A., Reed, D. S., Geisbert, J. B., . . . Davis, K. J. (2003). Pathogenesis of Ebola hemorrhagic fever in cynomolgus macaques: evidence that dendritic cells are early and sustained targets of infection. Am J Pathol, 163(6), 2347-2370. doi: 10.1016/S0002-9440(10)63591-2

Geisbert, T. W., & Jahrling, P. B. (1995). Differentiation of filoviruses by electron microscopy. Virus Res, 39(2-3), 129-150.

Glik, D. C. (2007). Risk communication for public health emergencies. Annual Review of Public Health, 28(1), 33-54. doi: 10.1146/annurev.publhealth.28.021406.144123

Google Trends. (2014). Google Trends - United States - Top Charts - 2014. Retrieved December 11, 2014, 2014, from http://www.google.com/trends/topcharts

Google Trends. (Past 90 days). Google Trends - Web Search interest. from http://www.google.com/trends/explore

44

Hampel, J. (2006). Different concepts of risk – A challenge for risk communication. International Journal of Medical Microbiology, 296, Supplement 1(0), 5-10. doi: http://dx.doi.org/10.1016/j.ijmm.2005.12.002

Heath, R. L., Seshadri, S., & Lee, J. (1998). Risk communication: A two-community analysis of proximity, dread, trust, involvement, uncertainty, openness/accessibility, and knowledge on support/opposition toward chemical companies. Journal of Public Relations Research, 10(1), 35-56.

Heide, E. A. (2004). Common misconceptions about disasters: Panic, the “disaster syndrome,” and looting. The first 72 hours: a community approach to disaster preparedness, 337.

Hewlett, B. S., & Amola, R. P. (2003). Cultural contexts of Ebola in northern Uganda. Emerging infectious diseases, 9(10), 1242.

Hulo, C., De Castro, E., Masson, P., Bougueleret, L., Bairoch, A., Xenarios, I., & Le Mercier, P. (2011). ViralZone: a knowledge resource to understand virus diversity. Nucleic acids research, 39(suppl 1), D576-D582.

Hyer, R. N., Covello, V. T., Organization., W. H., & Response, D. o. E. a. P. A. a. (2005). Effective media communication during public health emergencies : a WHO handbook Retrieved from http://www.who.int/iris/handle/10665/4351#sthash.X7rmjmdM.dpuf

Infanti, J., Sixsmith, j., Barry, M., Núñez-Córdoba, J., Oroviogoicoechea-Ortega, C., & Guillén-Grima, F. (2013). A literature review on effective risk communication and control of communicable diseases in Europe. Retrieved September 2, 2014, 2014, from http://www.ecdc.europa.eu/en/publications/Publications/risk-communication-literary-review-jan-2013.pdf

Janoske, M., Brooke Liu, and Ben Sheppard. (2012). Understanding Risk Communication Best Practices:A Guide for Emergency Managers and Communicator. College Park, MD: START, 2012: Report to Human Factors/Behavioral Sciences Division, Science and Technology Directorate, U.S. Department of Homeland Security.

Janssen, A. P., Tardif, R. R., Landry, S. R., & Warner, J. E. (2006). "Why tell me now?" the public and healthcare providers weigh in on pandemic influenza messages. Journal of public health management and practice : JPHMP, 12(4), 388.

Jardine, C., Hrudey, S., Shortreed, J., Craig, L., Krewski, D., Furgal, C., & McColl, S. (2003). Risk management frameworks for human health and environmental risks. J Toxicol Environ Health B Crit Rev, 6(6), 569-720. doi: 10.1080/10937400390208608

Kasperson, R. E., Renn, O., Slovic, P., Brown, H. S., Emel, J., Goble, R., . . . Ratick, S. (1988). The social amplification of risk: A conceptual framework. Risk Analysis, 8(2), 177-187.

Leffel, E. K., & Reed, D. S. (2004). Marburg and Ebola viruses as aerosol threats. Biosecur Bioterror, 2(3), 186-191.

45

Leroy, E. M., Rouquet, P., Formenty, P., Souquiere, S., Kilbourne, A., Froment, J. M., . . . Rollin, P. E. (2004). Multiple Ebola virus transmission events and rapid decline of central African wildlife. Science, 303, 387-390. doi: 10.1126/science.1092528

Lin, I., Petersen, D., & National Risk Management Research, L. (2007). Risk communication in action: the tools of message mapping. Cincinnati, OH: National Risk Management Research Laboratory, Office of Research and Development, United States Environmental Protection Agency.

Mitchell, S. W., & McCormick, J. B. (1984). Physicochemical inactivation of Lassa, Ebola, and Marburg viruses and effect on clinical laboratory analyses. J Clin Microbiol, 20(3), 486-489.

Murray-Johnson, L., Witte, K., Thompson, T., Dorsey, A., & Miller, K. (2003). Looking toward the future: Health message design strategies. Handbook of health communication, 473-495.

Mwanatambwe, M., Yamada, N., Arai, S., Shimizu-Suganuma, M., Shichinohe, K., & Asano, G. (2001). Ebola hemorrhagic fever (EHF): mechanism of transmission and pathogenicity. J Nippon Med Sch, 68(5), 370-375.

Nelkin, D. (1989). Communicating technological risk: the social construction of risk perception. Annual Review of Public Health, 10(1), 95-113. doi: 10.1146/annurev.pu.10.050189.000523

Ng, K., & Hamby, D. (1997). Fundamentals for establishing a risk communication program. Health Physics, 73(3), 473-482.

Ocowun, C. a. C. W. (2007). Ebola survivors still sick after seven years. Retrieved October 11, 2014, 2014, from http://www.newvision.co.ug/D/9/183/602136

Peters, R. G., Covello, V. T., & McCallum, D. B. (1997). The determinants of trust and credibility in environmental risk communication: an empirical study. Risk Analysis, 17(1), 43-54.

Phillips, B. D., & Morrow, B. H. (2007). Social science research needs: Focus on vulnerable populations, forecasting, and warnings. Natural Hazards Review, 8(3), 61-68.

Preston, R. (October 26, 1992). Crisis in the hot zone. The New Yorker.

Remien, R. H., & Rabkin, J. G. (2001). Psychological aspects of living with HIV disease: a primary care perspective. West J Med, 175(5), 332-335.

Renn, O. (1998). Implications of the hormesis hypothesis for risk perception and communication. Hum Exp Toxicol, 17(8), 431-438.

Reynolds, B. (2002). Crisis + emergency risk communication: by leaders for leaders. Atlanta, GA: Centers for Disease Control and Prevention.

46

Reynolds, B., Hunter-Galdo, J. H., & Sokler, L. (2002). Crisis + Emergency Risk Communication.. Book, Whole. V. F. Freimuth, A. Eberl-Lefko, L. Weinberg, E. Williams, C. R. Wood, & A. Zawislanski (Eds.),

Reynolds, B., & Seeger, M. W. (2005). Crisis and Emergency Risk Communication as an Integrative Model. Journal of Health Communication, 10(1), 43-55. doi: 10.1080/10810730590904571

Roels, T. H., Bloom, A. S., Buffington, J., Muhungu, G. L., Mac Kenzie, W. R., Khan, A. S., . . . Ksiazek, T. G. (1999). Ebola hemorrhagic fever, Kikwit, Democratic Republic of the Congo, 1995: risk factors for patients without a reported exposure. Journal of Infectious Diseases, 179 Suppl 1, S92-97. doi: 10.1086/514286

Roll Back Malaria (RBM) Partnership. (2014). Malaria endemic countries. from http://www.rbm.who.int/endemiccountries.html

Sampson, K. W., Kelly Morrison, Wen-Ying Liu, Anne P. Hubbell, Lisa Murray-Johnson, Joe. (2001). Addressing cultural orientations in fear appeals: Promoting AIDS-protective behaviors among Mexican immigrant and African American adolescents and American and Taiwanese college students. Journal of Health Communication, 6(4), 335-358.

Sandman, P. (2000). Responding to Community Outrage (Book review). Journal of Environmental Health, 63(4), 36.

Sandman, P., & Lanard, J.). Anticipatory guidlines.sandman.pdf.

Sandman, P. M., & American Industrial Hygiene Association. (1993). Responding to community outrage : strategies for effective risk communication. Fairfax, Va.: American Industrial Hygiene Association.

Schieffelin, J. S., Shaffer, J. G., Goba, A., Gbakie, M., Gire, S. K., Colubri, A., . . . the, W. H. O. C. R. T. (2014). Clinical Illness and Outcomes in Patients with Ebola in Sierra Leone. N Engl J Med. doi: 10.1056/NEJMoa1411680

Schlech, W. F., 3rd, Lee, S. H., Cook, J., Rozee, K. R., & MacIntosh, N. (1989). Passive transfer of HIV antibody by hepatitis B immune globulin. JAMA, 261(3), 411-413.

Sheppard, B., Janoske, M., & Liu, B. (2012). Understanding Risk Communication Theory:A Guide for Emergency Managers and Communicators. College Park, MD, START: Report to Human Factors/Behavioral Sciences Division, Science and Technology Directorate, U.S. Department of Homeland Security.

Sjöberg, L. (2001). Limits of knowledge and the limited importance of trust. Risk Analysis, 21(1), 189-198.

Slovic, P. (1999). Trust, emotion, sex, politics, and science: Surveying the risk-assessment battlefield (Reprinted from Environment, ethics, and behavior, pg 277-313, 1997). Risk Analysis, 19(4), 689-701. doi: Doi 10.1023/A:1007041821623

47

Steib, P. (2002). Communication in risk situations: Responding to the communication challenges posed by bioterrorism and emerging infectious diseases. Association of State and Territorial Health Officials.

Stern, J. (2014). Hell In The Hot Zone (Vol. 56, pp. 240). New York: Conde Nast Publications, Inc.

Takada, A., Robison, C., Goto, H., Sanchez, A., Murti, K. G., Whitt, M. A., & Kawaoka, Y. (1997). A system for functional analysis of Ebola virus glycoprotein. Proc Natl Acad Sci U S A, 94(26), 14764-14769.

Tan, S. B., Goh, C., Thumboo, J., Che, W., Chowbay, B., & Cheung, Y. B. (2005). Risk perception is affected by modes of risk presentation among Singaporeans. Annals of the Academy of Medicine, Singapore, 34(2), 184.

Thompson, D. (2014). The Dangerous Myth of America's Ebola Panic. The Atlantic. http://www.theatlantic.com/health/archive/2014/10/twice-as-many-americans-believe-in-witches-as-are-afraid-of-ebola/381682/

Wauquier, N., Becquart, P., Padilla, C., Baize, S., & Leroy, E. M. (2010). Human fatal zaire ebola virus infection is associated with an aberrant innate immunity and with massive lymphocyte apoptosis. PLoS Negl Trop Dis, 4(10). doi: 10.1371/journal.pntd.0000837

WBUR (Producer). (2014). Harvard Poll On Ebola Risk Finds Public Dazed And Very Confused | CommonHealth. Retrieved from http://commonhealth.wbur.org/2014/10/harvard-study-on-ebola-risk-finds-public-dazed-and-very-confused

Weingartl, H. M., Embury-Hyatt, C., Nfon, C., Leung, A., Smith, G., & Kobinger, G. (2012). Transmission of Ebola virus from pigs to non-human primates. Sci Rep, 2, 811. doi: 10.1038/srep00811

WHO. Ground zero in Guinea: the outbreak smoulders – undetected – for more than 3 months. A retrospective on the first cases of the outbreak. Retrieved October 12, 2014, 2014, from http://www.who.int/csr/disease/ebola/ebola-6-months/guinea/en

Wilson, J. A., Hevey, M., Bakken, R., Guest, S., Bray, M., Schmaljohn, A. L., & Hart, M. K. (2000). Epitopes involved in antibody-mediated protection from Ebola virus. Science, 287(5458), 1664-1666.

Wolbarst, A. B. (2001). Solutions for an environment in peril. Baltimore: Johns Hopkins University Press.

Wong, G., Kobinger, G. P., & Qiu, X. (2014). Characterization of host immune responses in Ebola virus infections. Expert Rev Clin Immunol, 10(6), 781-790. doi: 10.1586/1744666X.2014.908705

48

Wool-Lewis, R. J., & Bates, P. (1998). Characterization of Ebola virus entry by using pseudotyped viruses: identification of receptor-deficient cell lines. J Virol, 72(4), 3155-3160.

Wray, R. J., Kreuter, M. W., Jacobsen, H., Clements, B., & Evans, R. G. (2004). Theoretical perspectives on public communication preparedness for terrorist attacks. Fam Community Health, 27(3), 232-241.

Ye, L., Lin, J., Sun, Y., Bennouna, S., Lo, M., Wu, Q., . . . Yang, C. (2006). Ebola virus-like particles produced in insect cells exhibit dendritic cell stimulating activity and induce neutralizing antibodies. Virology, 351(2), 260-270. doi: 10.1016/j.virol.2006.03.021

Zajonc, R. B. (1980). Feeling and thinking: Preferences need no inferences. American psychologist, 35(2), 151.

Zaki, S. R., Shieh, W. J., Greer, P. W., Goldsmith, C. S., Ferebee, T., Katshitshi, J., . . . Peters, C. J. (1999). A novel immunohistochemical assay for the detection of Ebola virus in skin: implications for diagnosis, spread, and surveillance of Ebola hemorrhagic fever. Commission de Lutte contre les Epidemies a Kikwit. Journal of Infectious Diseases, 179 Suppl 1, S36-47. doi: 10.1086/514319

49