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How to Evaluate the Dynamic Public Health Risk of COVID-19

We are seeing coronavirus or COVID-19 emerging across the globe including in our own back yard. What should we be considering with respect to evaluating COVID-19 risk, making sense of numbers, and for whom this is a health risk?
What do risk and crisis communication theories tell us about how to communicate about COVID-19 risk with the public and how might we think about this evolving public health threat for the protection of our community, our families, and our own health?

Making Sense of COVID-19 Numbers

Although the numbers keep changing there are some facts and principles we can consider for where to turn to, what to be cognizant of, and how to evaluate this evolving public health risk threat. There are also not only the number of cases reported worldwide and at home that speak to the spread of disease, but there are numbers that speak to severity of disease risk
  • the case fatality rate (CFR), which measures the risk that someone who develops symptoms will eventually die 
  • and there is R0 – the reproductive number or, how many people a given infected person is likely to infect. 
I address and make sense of these numbers first in evaluating how the public might think about and respond to the evolving COVID-19 public health threat. Subsequently, a discussion addresses the social aspects of risk communication about COVID-19 to consider for effectively communicating with the public and contextualizing public reaction.

Currently, as of March 12th, COVID-19 has reared its head worldwide infecting an estimated 125,288 and 4614 deaths according to the World Health Organization (WHO) with numbers continually evolving. In the U.S. there are 1215 cases and 36 deaths reported.

Case fatality rate (CFR)
According to mathematician Dr. Adam Kucharski at the London School of Hygiene & Tropical Medicine, the CFR is estimated to be between 0.5 and 2% with an estimated risk for eventual death at 1%, with 0.1% for young and at 10-18% risk for those older than 70. By comparison, about 0.1% of those infected with influenza die. From these numbers, epidemiologists estimate the CFR is about 10 fold that of influenza. Key aspects of some of the early U.S. cases to make note of is that some of them are thought to be “community acquired” that is, they are not travel related. This signals a significant departure from prior reports about transmission being linked to travel.

It is believed that the biggest threat of death from COVID-19 is for those who are over the ages of 70, and who have pre-existing co-morbid health conditions including cardiovascular disease, compromised immune systems, lung disease, and those who smoke. That being said, we all need to be vigilant and keep up with hand washing hygiene, staying at home if we feel sick, resting and keep social distance, and avoiding unnecessary travel.

As a way to process the dynamic (changing) public health COVID-19 information, many including the WHO have made risk comparisons to something the public is familiar with namely the flu or influenza risk. According to WHO experts, both influenza and COVID-19 cause respiratory symptoms and are spread through small droplets from the nose or mouth. As for differences, COVID-19 appears to cause more severe clinical symptoms than flu with a risk of pneumonia and there is no available vaccine. If anything positive comes out of COVID-19, it might be that more people are willing to wash their hands more frequently, stay home if they are sick, and possibly get their flu vaccine. WHO and others globally have struggled to gain accurate mortality estimates given that many infected with COVID-19 have mild symptoms never showing up at a hospital.

That said, the numbers are the tip of the iceberg; many more people are getting infected than are getting reported and definitions of what constitutes a case have changed (the definition of a COVID-19 case now considers clinical features including the diagnosis of pneumonia in addition to molecular diagnostic testing). Accurate estimates are difficult to come by and continually evolving.

Reproductive number (R0)
We also hear about R0, the reproductive number, or how many people a given patient is likely to infect. Currently, R0 for COVID-19 is estimated at 3-4 indicating that an infected person will infect at least an additional 3-4 people sick. From a public health perspective, the goal is to reduce R0 to less than 1 meaning that an infected person doesn’t infect 1 or more people.

Four things go into calculating R0. Brief definitions are described followed by which components public health officials can target to reduce risk.
  • Duration speaks to how long someone is infectious and currently, it is estimated individuals with COVID-19 are infectious 1-2 weeks. 
  • Opportunity involves the number of people an infected individual comes into contact with every day they are sick. 
  • Transmission probability is the measure of chance that the infection will actually get across during an interaction. 
  • Susceptibility measures the chance the other person will actually acquire the infection and become infectious themselves. 
Multiplying these four components yields the reproductive number R0 i.e., how many people a sick person is likely to infect.

Per Dr. Kucharski, susceptibility is the easiest target to reduce if a vaccine is available. If a vaccine is not available, as is the case with COVID-19, then reducing “opportunities” through social distancing, encouraging hand-washing, sneezing into one’s elbow, staying home if sick, reducing unnecessary travel are all public health recommended actions. Additionally, knowing which groups are at most risk, public health officials should invest efforts to the extent possible into reducing transmission among high risk groups namely those older than age 70 and or groups with cardiovascular disease, elderly and smokers, and protecting healthcare workers on the frontlines.

Considering Not Just the Numbers but How Social Aspects & Communication Networks Come into Play to Understand Emerging Public Health Risk Threats & Reactions

Four risk communication theories come to mind when considering the emerging and dynamic public health risk threat of COVID-19 –now a pandemic disease (it’s official according to WHO) – to understand spread of information and public reactions:
  • crisis and emergency risk communication otherwise known as CERC; 
  • social trust theory, 
  • social amplification of risk framework (SARF); 
  • and social network contagion theory. 
Each of these risk communication frameworks explain public reaction and the role of risk perception, but also explain and suggest approaches and communication strategies to public health risk communication. Before describing the 4 risk communication frameworks, a brief note distinguishing crisis from other types of risk communication is warranted.

Risk communication comes in many forms. 

Crisis communication involves communicating about a time sensitive risk for which the response is evolving, there is a potential sudden or extreme threat to a large segment of the population, and there is no prior established agreement or protocol for how to proceed. This contrasts with other risk communication types for which the danger and way to manage it has already been established through scientific research and is accepted by most of the audience (e.g., post-surgical protocols to reduce secondary complications like blot cots).
Other types of risk communication have as their goal to encourage groups to work together to reach a decision about how to manage a risk (e.g., community response to environmental health & hazard risk communication).

Crisis and emergency risk communication (CERC)

Crisis and emergency risk communication as is the case with COVID-19, begins with communicating or explaining the extent of potential harm to the public’s health. Government agencies like the Centers for Disease Control and Prevention (CDC) and the WHO are expected to respond and communicate with the public and the global community to make information and resources available and accessible.

The CDC has learned from many prior risk events such as 9/11 and SARS, to communicate early and often, to be transparent about what is known and not known about evolving risks, as well as what is being done to resolve uncertainties.
The case of COVID-19 involves additional levels of risk communication and challenges given the global scope.

Crisis and Emergency Risk Communication (CERC) [1,2] is a risk framework developed in response to 9/11 by Barbara Reynolds at the CDC . Communicating in a crisis is distinct in which people may process information differently. The CDC recognized that a departure was needed from prior risk responses when the risk communication approach was grounded principally in reducing uncertainty. A pandemic disease outbreak like COVID-19 calls for consideration of CERC.

Crisis and emergency risk communication occurs unexpectedly, may not be in an organization’s control, requires an immediate response (i.e., is time sensitive), and if communication is mishandled may cause harm to an organization’s reputation. Put another way, the right message at the right time from the right person can save lives!

By definition, emergency and crisis communication is often and inherently accompanied by a high degree of uncertainty. Broadly speaking, CERC unfolds in phases over time with unique needs and strategies for each phase (as well as short and long term strategies) and has two components: process and content. There is the process by which those involved craft a response and then there are the messages to be crafted to communicate with the public. The framework offers best practices to guide the process and content of a risk communication approach.

CERC best public health risk communication practices include:
  1. Explain what is known, 
  2. Explain what is not known, 
  3. Explain how or why the event happened, 
  4. Promote action steps the public can take, 
  5. Express empathy, (6) Express accountability, and (
  6. Express commitment. 
CERC principles include be first, be right, be credible. Additionally, steps for successful crisis communication involve:
  1.  having a communication plan, 
  2.  being the first source of information, 
  3.  expressing empathy early, (
  4.  showing competence and expertise, and 
  5.  remaining honest and open. 
Finally, building trust by providing and sharing consistent and transparent messaging is important for successful communication.

Social Trust Theory

Trust plays a significant role in individuals’ responses to public health crises [3,4].
Social trust theory [3-5] posits that when perceived control of risk is not at the individual level, trust becomes a major and perhaps one of the most important variables in public acceptance of risk management and recommendations. When people perceive a risk, they only put into practice messages that come from sources they perceive as trustworthy and credible.

The single biggest contributor to increasing trust is an organization’s ability to show empathy. Implications are that information alone will not communicate risk effectively if trust and credibility are not established first. Trust is fragile with it typically being created rather slowly over time but can be destroyed in an instant.

There are many dimensions of trust ranging from:
  • showing empathy, degrees of transparency, objectivity (free of biases), 
  • perceived competence (degree of technical expertise), 
  • fairness (adequate representation of viewpoints), 
  • consistency (previous communication efforts), 
  • sincerity (honesty and openness), 
  • and faith (perception of good will). 
These all factor into building trust and effective public health risk communication. Public health recommendations depend on trust in the message.

Constraints to Effective Risk Communication. 

It is important to recognize that constraints to effective risk communication are likely but recognizing these constraints is the first step toward potentially overcoming them to the extent that is possible. Constraints range from the organizational and institutional to the audience side. 

From an institutional/organizational perspective, constraints to effective risk communication can include:
  •  inadequate resources, 
  • management apathy, 
  • potentially conflicting roles of responsibility (e.g., what occurred in the case of COVID-19 with the White House informing the CDC that all communication needed to be vetted by the White House before being shared with the public), 
  • corporate protection requirements, i
  • nsufficient information and uncertainty, 
  • institutional trust to challenges of international risk communication with differing governmental cultures and approaches to public health risk communication. 
Constraints on the audience side may include emotional responses of panic to mistrust to difficulties making sense of the magnitude and severity of risk information and who is really at most risk. In general, principles of process should govern approaches to overcoming constraints, with principles governing such as communicating early and often, honestly, clearly, and compassionately while listening and answering specific concerns, and discussing sources of uncertainty. 
The CDC has learned from many prior crisis communication experiences about what risk communication strategies to avoid. 

Communication mishaps

Communication mishaps that public health agencies, academic institutions, organizational institutions, the government should avoid include 
  1.  mixed and conflicting messages from multiple sources, 
  2.  late release of critical information, 
  3.  overly reassuring the public and delivering unrealistic communication, 
  4.  advice without a reality check, 
  5.  employing a paternalistic approach to communication, (
  6.  unaddressed or uncorrected myths and rumors, 
  7.  spokespersons who engage in poor behavior or who appear to not address emotional elements  of the crisis (e.g., making light of a serious situation), 
  8.  public power struggles, and 
  9.  perception that certain groups are receiving preferential treatment. 
These are all communication elements that should be avoided in a risk or crisis situation.

University of California, Irvine (UCI) has done an excellent job coordinating among the administrative officials and relevant agencies in Orange County, California (southern CA) to communicate with the local community early and often about the coronavirus. UCI has been transparent about what is known and not known through multiple channels ranging from pop-up public health booths, videos, websites, emails to the entire community from leaders, social media, and expert panel discussions.
This is stands in contrast to a poor and unorganized response by the U.S. government resulting in confusion, doubt and uncertainty among the U.S. public.

Singapore and Canada by contrast have successfully communicated with the public early on with sincere and relatable messages, offering information about resources, testing, transparency, and self-quarantine demands, as well as protection for the most vulnerable groups.

Perceptions of risk

Perceptions of risk needs to also be taken into consideration in crisis communication depending on the nature of the risk. For instance, whether a risk is perceived as voluntary or involuntary, personally controllable vs controlled by others, familiar versus exotic, natural in origin versus manmade, or reversible versus permanent. A risk communication framework that examines the effects of risk perceptions is the social amplification of risk framework.

Social Amplification of Risk Framework (SARF) 

Social Amplification of Risk Framework (SARF) examines how media coverage, institutions, and social groups amplify or attenuate risk perceptions. This meta-level framework focuses on examining how volume and tone of media coverage, story selection, and framing risk impacts the spread and potential stigmatization of information.

SARF also highlights how social activities generate and mutate risk signals, how emotional elements are tapped into by the media (e.g., food outbreaks, infectious disease outbreaks) and how secondary ripple effects occur (e.g., impacts on the stock market, school closures, industry and event closures and their economic impacts).

In the case of COVID-19, SARF brings to light the potential stigma inherent in framing a public health threat such as COVID-19 by its location of origin, the Wuhan virus, as it was originally referred to.
Social activities can magnify the consequences of a risk event and risk framing often in unexpected ways. This can inadvertently result in groups of people, communities or industries being stigmatized. We witnessed this early on with the media coverage focusing on the crisis originating in the Hubei Province, in the city of Wuhan, China. Reactions by residents of Orange County southern California, and across the U.S. avoiding Chinatown, Chinese restaurants, or people of Chinese heritage as a result of the emerging coronavirus health threat. Paying attention to the framing and use of names is important to avoid stigmatizing certain groups of people, places, or industries.

Additionally, as SARF highlights we witness how the spread, volume, and amplification of news about COVID-19 results in secondary ripple effects impacting the world economy, the stock market, but also the travel industry, schools, conferences, events, and venues, all experiencing economic loss due in large part to risk perceptions. At the local level, closures can have devasting economic impacts resulting in considerable economic hardship among ordinary citizens. News and social media can be credited with amplifying risks and risk perceptions (or attenuating risk perceptions) to the extent that it has real economic consequences.

Local public health agencies and institutions set the pace of debates and it is important to remember that risk communication is not controlled by a single authority but rather by a coordinated inter-agency effort. The main and first priority of public health agencies is and must be to save lives and prevent further harm to the public with economic harm being secondary. Risk communication may unfold in a non-linear fashion and may take unexpected turns.

When experts including the government refuse or are slow to provide information, the public is quick to fill the void often with rumors. Currently, WHO is calling the situation an “infodemic” referring to an overwhelming amount of information – some accurate some inaccurate – spreading particularly on social media and the Internet. False statements range from conspiracy theories of the virus’ origin to expressions about the magnitude of the spread, severity of the virus, and who it affects (more men than women). Such infodemics come about in part due to the complexities and the global scale of the crisis.

To avoid negative secondary and tertiary effects (to the extent possible) of the mass spread of information and misinformation, communicating risks early and often, as well being transparent about what is known and unknown, and paying attention to key and influential communication networks is critical in dampening social amplification and social stigmatization risks.

Social Network Contagion Theory applied to risk communication, Social Media, and the Spread of Information and Misinformation 

As providers of information the media play a vital response in COVID-19. The new norm of communicating public health risk today is through social media. We witness not only citizens but political and public health official posting the latest public official recommendations and policies on social media. Social media allow various stakeholders and the public to connect with each other online and share public health risk information, videos, comments, memes, news briefs, opinions, and experiences.  Public discussions include sharing experiences (e.g., getting lonely during quarantine), information, articles, updates about COVID-19 with various engagement strategies afforded by social media platforms. Social media offers a way to stay connected while we are in isolation (e.g., state and country lockdown).

Harnessing the Benefits of Social & Mobile Media Communication Networks for Public Health Information Dissemination. 

It is important to remember that social media can be a valuable component of public health risk communication. Public health agencies and citizens increasingly turning to social media and online communities given its speed and nimbleness in disseminating relevant risk information. Not only does it add a channel to reach people, but it gives organizations almost instant and continuous feedback on what people want to know about the emerging public health risk and what they are concerned about (e.g., testing kits, school and event closures, travel bans).

Social media also allow organizations to respond more quickly and flexibly as situations change to offer dynamic responses. These relatively new information ecologies have the potential to increase an organization’s credibility and trust. Much of the public follows social media e.g., Twitter feeds and facebook using #coronavirus or #COVID19 to follow any messages of their choosing, but hopefully also credible organizations like the CDC, WHO, but also academic universities, hospitals, public health departments, podcasts by doctors, as well as following ordinary citizens who share personal experiences or the latest scientific and media reports with family, friend, and co-worker networks.

The advantages of such an online social or communication network audience is that interest and engagement level is high. Online Twitter users for example might be more willing to change their behavior. Social media is nowadays the place many, especially young people, go to get the latest breaking news. Feedback is instant with topics of conversations easily tracked. For assessing risk perception or shifts in risk perception over time, social media provides a good signal of the public’s wants, needs, and perceptions. This being said, the caveat of social media audiences is that they have more control over who they choose to follow, and what risk messages they consume and share.

Social media communication networks present a new communication paradigm in which the hypodermic needle communication approach of one-way delivering, diffusing, and disseminating public health messages from a central source to individuals or the public has shifted to being multidirectional and participatory in nature and discourse. Audiences get to choose what they consume and pass on. This has implications for designing and sharing public risk messages with new models of communication in need of development. Intentional and incidental health communication transpires online now as well as in person. Social media users get to decide with whom, how, and what they pass on, share and amplify.

While social media has the potential to propagate misinformation it is a platform that also allows for correcting misinformation. Faster response during emergencies and gaining a better understanding of audience needs and perceptions are major benefits. Public health risk communicators who want to get out a message rapidly to potential audiences, might want to consider sharing essential public health risk messages with network influencers who will be key to spreading public health messages more quickly and credibly. Knowing who the influencers are ahead of time helps. Audiences will trust social network opinion leaders and will more readily accept and share messages coming from insider leaders.

Remember Common Sense Prevention Practices such as Handwashing Hygiene, social distancing, and staying home if you are sick

Effectively communicating about the coronavirus is similar to communicating risk about many viruses. Most important is to remember everyday prevention strategies like hand washing hygiene with soap and water (both are really important!) and staying home if you feel sick. As the CDC states, while the potential public health threat posed by COVID-19 is high for the population, individual risk is dependent on exposure. That is why, just like with prevention of flu and any other infectious and respiratory diseases, prevention involves practicing everyday handwashing hygiene, taking precautions to stop the spread of germs, getting your flu vaccine, staying home if you are sick, and avoiding unnecessary travel.

By Suellen Hopfer, PhD

Professor Suellen Hopfer, PhD, CGC is Assistant Professor of Population Health & Disease Prevention in the Program in Public Health at University of California Irvine (UCI) in Southern California.
Her training is in human genetics (M.S. Human genetics/genetic counseling, University of Arizona) and health communication (PhD, Pennsylvania State University) with a post-doctorate training in longitudinal methods, social networking and prevention. She was a genetic counselor/clinician for 10 years prior to becoming a public health communication professor. She is a risk & health communication scholar. Current research projects include: designing and implementing clinical, multi-level HPV vaccine interventions in clinical settings, developing culturally grounded vaccine decision narratives to reach various cultural community groups; modeling communication networks on social media; examining family communication in stroke recovery and eliciting stroke recovery narratives, and interviewing environmental justice informants about climate change and community health impacts.


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