Case Study

What drives COVID-19 and how can we overcome it?

COVID-19 impacted the daily lives of people across the globe for years, and its presence lingers. As science communicators, we can support public and professional communities in times of need by creating clarity from complexity.

About the issue

In December 2019 news was emerging of a severe acute respiratory disease spreading quickly in the Wuhan region of China. We knew that something big was happening. As the outbreak grew rapidly, we watched a firehose of information inundate societies—not all of it reliable or parsed easily. As communication professionals who live and breathe science, we wanted to help increase understanding of this urgent situation.

Opportunities for intentional impact

As the coronavirus outbreak gained steam, we saw an opportunity to research, synthesize and share vetted data publicly—to create a hub of digestible information rooted in credible sources and our industry insight. Our aim was to transform complexity into knowledge, and to do so quickly. As a solution, we rallied to publish a thorough but digestible case study on our website, including science and data visualizations to deepen understanding of the most vital topics. As the pandemic progressed, we updated the case study regularly, tracking the situation and sharing what we knew. And it made an impact. We gave permission for the use of our visualizations to help others educate their audiences. Versions of our figures were published in Nature, and used in talks for organizations, universities and institutions around the world.

Reliable during uncertain times

What started as a strong desire to understand the novel coronavirus developed into a concentrated cross-team initiative involving scientific storytelling, science writing, design, and development. Through an interdisciplinary mindset we created visual solutions and writing to make complex topics clear to a broad audience.

We published our first version of the case study on our website on February 13, 2020. A month later the WHO declared a global pandemic.

As the pandemic progressed, as variants emerged and vaccines were created, we added new information and regularly updated the data we had, often daily. We scoured government sources, peer reviewed publications, preprints and reputable news outlets. As of our last addition on April 5, 2022, we had updated the case study 148 times.

The final version of the case study included information on signs and symptoms, spread of infection, the anatomy and mechanism of action of SARS-CoV-2, comparisons with other outbreaks, vaccines and variants.

First signs

One of the earliest essential pieces of information we developed to share was explaining COVID-19 signs and symptoms because people needed to know if symptoms they were experiencing could be the result of a SARS-CoV-2 infection. The main symptoms of COVID-19 were recognized and established quickly. But as the pandemic progressed, new symptoms were reported, and we carefully updated the case study as needed.

As of our last update to the case study in April 2022, the Centers for Disease Control & Prevention (CDC) believed that symptoms of COVID-19 may appear in as few as two days or as long as 14 after exposure. Individuals with symptoms including fever, coughing, and shortness of breath were to self-isolate and seek COIVD-19 diagnostic and medical advice.1,2 The clinical spectrum of COVID-19 ranged from mild, cold-like symptoms to severe pneumonia, respiratory failure, and in some cases, death.2

Image reflects information known as of April 5, 2022. Image Reference1 Anyone can be infected by the virus that causes COVID-19, but certain populations appeared to be more vulnerable to severe infection: evidence suggested that older individuals and those with underlying medical conditions are more likely to experience complications or hospitalization.2

Spread of infection

Tracking the spread of infection was essential to know where people should consider taking extra precautions to avoid exposure and be aware of the burden on the health care system.

As of April 5, 2022, there had been 482,400,945 confirmed COVID-19 cases. Of the total cases, 154,464,736 individuals had recovered, and 6,128,212 had died, of which 977,913 were from the U.S.

Throughout the early stages of the pandemic, we also tracked the case fatality ratio (CFR) to understand the relative risk of death from COVID-19. The CFR for different groups of people and countries helped guide resource allocation and policy decisions. It was also important to keep in mind that the level of transmission in a population may be underestimated if individuals with mild or no symptoms are missing from the data or if under-served groups have decreased access to health care or testing.3

On Feb. 28, 2020, the WHO raised the Global Risk Assessment level for COVID-19 from high to very high.4 On March 11, 2020, the WHO Director-General announced that COVID-19 can be characterized as a pandemic. Person-to-person spread (or community spread) has since occurred in countries all over the world.

Visualizing SARS-CoV-2

It was important to look at the structure of SARS-CoV-2 and its mechanism of disease to understand how the virus was interacting with human cells and how people might start to develop immune responses against the virus.

From the beginning of the COVID-19 outbreak, the combination of many expedited studies had revealed an unprecedented amount of information for a new disease, including the causative virus (SARS-CoV-2), its genetic sequence, PCR assays, and serological analyses. Efforts were rapidly ongoing with the aim of quickly designing effective treatments, such as a vaccine or antiviral drug.

Once in the body, SARS-CoV-2 recognizes and attaches to a transmembrane protein called ACE2 found mainly on cells that line our airways. The effectiveness of SARS-CoV-2 in triggering respiratory disease may be due to the evolved structure of the Spike (S) protein, which contains the receptor-binding domain for ACE2 and creates the virus’s recognizable “crown” shape. After binding to an ACE2 homodimer, the virus enters the cell through a process called receptor-mediated endocytosis. Inside the cell, the virus releases its RNA and takes advantage of the host cell’s machinery, allowing it to reproduce, escape, and continue infecting human tissue.

How COVID-19 compares to other outbreaks

As more cases emerged, medical professionals and researchers were able to identify distinguishing traits of COVID-19.

We wanted to put the pandemic into context: How it is different from other types of disease and how is it similar? How does it compare to other pandemics and epidemics? A table offered this perspective.

What we knew and what we were learning about vaccines and variants

The pandemic continued to evolve with the release of vaccines and as new variants emerged. People still needed to understand their own risks as both the virus and the response from the scientific and medical communities changed.

As more people were getting vaccinated, public health recommendations were being updated to reflect the new situation. As of May 13, 2021, the CDC’s official guidelines for the U.S. stated that fully vaccinated people no longer need to wear a mask or physically distance in most settings. These updates were a result of the high efficiency of the EUA COVID-19 vaccines and a growing body of evidence that fully vaccinated people were less likely to have an asymptomatic infection or transmit SARS-CoV-2 to others.20

As of April 2022, all EUA and FDA-approved COVID-19 vaccines being distributed were highly effective in preventing COVID-19. In international, randomized, placebo-controlled studies, the Pfizer-BioNTech and Moderna COVID-19 Vaccines were 95% and 94.1% effective in preventing COVID-19 disease.21,22 The Janssen vaccine was 77% effective in preventing severe/critical COVID-19 occurring at least 14 days after vaccination and 85% effective in preventing severe/critical COVID-19 occurring at least 28 days after vaccination.23

There was a growing body of evidence that suggested that fully vaccinated people were less likely to have an asymptomatic infection and potentially less likely to transmit SARS-CoV-2. In addition, preliminary studies showed some protection against emerging variants of concern (VOC), most notably the Delta Variant (B.1.617, originally identified in India), which showed increased transmissibility and reduced neutralizing antibody response and was the main variant circulating in the United States at the time;24 and the Omicron Variant (B.1.1.529, originally identified in South-Africa), which was believed to spread more easily than the original SARS-CoV-2 virus.25

Preventative measures such as mask use and social distancing continued to be important and were still recommended in public indoor spaces for both vaccinated and unvaccinated individuals.20

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  25. CDC. Omicron Variant: What You Need to Know.

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    The contents of this Case Study, including scientific visualizations, tables, and visual plots, are © 2020 Cognition Studio Inc, all rights reserved. The content of this Case Study is provided to the public strictly for educational purposes. The Case Study relies on publicly available data from multiple sources that do not always agree. As a result of this, Cognition Studio disclaims any representations and warranties concerning the Case Study’s accuracy. Reliance on the Case Study for medical guidance or use of the Case Study for commercial use is strictly prohibited.