The New Coronavirus: What Science & Experience Can Tell Us
Published March 13, 2020
As the new coronavirus continues its spread in the United States and worldwide, elected officials, healthcare providers, and private citizens are grappling with the wide-reaching implications of the pandemic. In uncertain times, it's important to focus on evidence-based information about the disease, efforts to mitigate its spread, and prospects for a vaccine or treatments.
In an effort to provide a topline view of what the public needs to know about the virus, the Academy brought together Julie Gerberding, MD, MPH, Executive Vice President and Chief Patient Officer, Strategic Communications, Global Public Policy, and Population Health at Merck & Co. and former Director of the Centers for Disease Control and Prevention, and Michael Osterholm, PhD, MPH, Director of the Center for Infectious Disease Research and Policy at the University of Minnesota, to share insights from their extensive experience, as well as from the latest research. In a webinar held on March 12, 2020, both Gerberding and Osterholm addressed the challenges ahead and the opportunities for action.
Perspective and Preparedness
- The global health community has successfully addressed multiple pandemics over the past two decades, including the coronaviruses SARS and MERS, H1N1 influenza, and Zika virus.
- The new coronavirus is highly transmissible and challenging to contain. Public health efforts are focused on slowing the spread within communities.
Dr. Gerberding began the webinar with a reminder that while this strain of coronavirus is new, it is not the first disease to threaten the global population. “We have a lot to learn about how this virus spreads and how we can intervene in that process...but we have a foundation of experience in previous outbreaks,” Gerberding said. “Each time we have one of these new outbreaks, we learn things, our preparedness takes a step forward, and we need to...develop some confidence that we're going to figure this one out too.”
While the new coronavirus was detected quickly in China and reported to global health authorities, limited access to testing, both in China and around the world—including in the United States—have hampered efforts to understand the scope of infections worldwide. Gerberding explained that China’s “extraordinary measures” to contain the virus limited spread within the country and delayed transmission to other countries.
Despite these containment efforts, the new coronavirus has spread to more than 110 countries in just three months, a fact Gerberding deems “unsurprising” given its high transmissibility.
With containment no longer a priority, countries and communities worldwide are enacting measures to slow the spread of the virus.
The New Coronavirus: Origin, Transmission, Vulnerable Populations
- The new coronavirus spreads primarily through person-to-person contact.
- Most cases are mild. Older individuals and those with underlying medical conditions are at greatest risk of developing serious complications.
- Much remains unknown about the new coronavirus. The case fatality rate is likely to evolve as the disease spreads, and these numbers may vary by country.
Origin and Transmission
Coronaviruses, named for the characteristic “crown” of protein spikes that jut from the viral surface, commonly infect humans, causing mild cold symptoms. The new coronavirus strain, SARS-CoV2 (commonly referred to now as the “new coronavirus” or “COVID-19"), originated in bats, evolved to infect small mammals, and ultimately “spilled over” into the human population. Because the virus is not native to humans, “we have no reason to believe anyone is immune to this,” Gerberding said.
The new coronavirus is highly transmissible. Dr. Osterholm explained that the reproduction number, or the R0, is estimated to be between 2 and 3—meaning that without precautionary measures, each infected person will pass the infection to at least two others. Comparatively, pandemic influenza has a R0 of about 1.2. The new coronavirus spreads primarily from person-to-person through aerosolized droplets released when an infected person coughs or sneezes. Masks can help prevent spread when worn only by sick individuals, as can isolation and covering sneezes and coughs. Osterholm noted that “we have very little data” on the viability of the new coronavirus on surfaces. “I don’t want to downplay the importance of handwashing...but surface contamination is not something people should be preoccupied with,” he said. [Update: According to a March 17, 2020, study by the NIH, "Scientists found that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was detectable in aerosols for up to three hours, up to four hours on copper, up to 24 hours on cardboard and up to two to three days on plastic and stainless steel."]
Approximately 80 percent of coronavirus infections are mild, causing fever, dry cough, and fatigue that resolve with no complications. However, older patients, and those with pre-existing medical conditions including cardiovascular disease, diabetes, or lung disease are at higher risk of potentially severe complications. These include shortness of breath and pneumonia, which may require medical intervention and intensive respiratory support.
The World Health Organization (WHO) estimates the case fatality rate of the new coronavirus at 3.4 percent, although some studies found fatality rates between 1 and 2 percent. “That’s still 10 to 20 times higher than seasonal flu,” Osterholm said. He noted that case fatality varies among countries, a trend he anticipates will evolve as the disease spreads worldwide. Factors such as the overall age of the population, along with rates of cigarette smoking and comorbidities such as obesity, are likely to influence the fatality rate.
Slowing the Spread in Communities
- Slowing the spread of the new coronavirus is critical for minimizing impacts on the healthcare system and protecting vulnerable populations.
- Common sense measures can significantly impact community spread, including minimizing large group gatherings and staying home when ill.
- Testing is critical for understanding the extent of community spread; prevalence of testing will increase in the coming weeks.
Osterholm emphasized that coronavirus will be a concern for months, rather than days or weeks. “It’s very important that we understand what we're talking about today is a long haul,” he said. He also cast doubt on the prospect that that the new coronavirus may decrease in prevalence as the weather warms, noting that the earlier coronavirus MERS emerged in the Middle East, in temperatures as high as 110°F. “Of the previous 10 pandemics, 2 started in the winter, 3 started in the spring, 2 started in the summer, and 3 started in the fall,” he said.
Widespread closures and social distancing measures enacted in China did help to slow disease spread, and other countries are enacting similar restrictions, such as cancelling large gatherings, limiting travel, closing schools and houses of worship, and encouraging telecommuting when possible. Although, Osterholm did note that little is known about the potential for the disease to resurface once restrictions are eased, and such measures are deeply disruptive to everyday life, often having downstream consequences for families, businesses, and essential services. Osterholm explained that while children appear to be largely unaffected by the new coronavirus, little is known about the role of children in spreading the illness.
Gerberding acknowledged the difficulties of balancing disease suppression efforts with maintenance of basic services. “We also have to concentrate on keeping our societies functioning—people need goods and services,” she said.
Reducing Healthcare Burden
Slowing disease spread is essential to reducing the burden on healthcare systems, which have neither space, staff, nor equipment to manage large numbers of critically ill patients. “If 100 cases of infection occur today, and they need high-intensity medical care, that’s a very stressful situation for any healthcare system,” Osterholm said. “If you are able to stretch them out, 10 new cases every week for 10 weeks...that may very well have a big impact on the overall outcome for patients.” Shortages of personal protective equipment, including respirator masks, contribute to the urgency surrounding moves to stanch spread of coronavirus.
Gerberding addressed the lack of widespread testing in the United States, noting that in addition to large medical diagnostics companies, some medical institutions are also developing coronavirus tests. “Over the next few days, we're no longer going to see testing as the bottleneck that it was in the early phase,” she said.
Increased testing access is likely to usher in a “catch-up period,” where, according to Gerberding, the public may “feel like the outbreak is moving faster than it really is.” Widespread testing is critical to “filling the gaps” in understanding both the prevalence of the virus in communities as well as the range of disease presentations. “The important thing...is that we get the broadest understanding of who is infected with disease, who is infected with mild symptoms, who is exposed and infected but not symptomatic, and who has been exposed but didn’t get sick,” Gerberding said.
Both Gerberding and Osterholm believe it’s likely that community spread is more prevalent than current testing has indicated, mainly because testing has focused on patients with severe disease. “We’re looking at the tip of an iceberg, but we really don’t know how big the iceberg is,” she said.
The Future: Vaccines and Treatment
- More than 40 companies are working on a coronavirus vaccine and treatments.
- Treatment options will likely emerge before a vaccine, which is expected to take 1-2 years.
A vaccine to prevent the new coronavirus is “the holy grail,” said Osterholm, but it’s a vision unlikely to be realized in the near term. Since the SARS outbreak in 2003, “biotech and biopharmaceutical capabilities have moved ahead by light years,” Gerberding said, and more than 40 companies are working to develop a coronavirus vaccine and treatments. Despite a strong start to the vaccine development process—Gerberding said there are “many more candidate vaccines than we've ever had at the beginning of a new infectious disease outbreak”—experts anticipate that development, testing, and widespread vaccine availability will take 1-2 years.
Treatment options are likely to emerge in the near-term, although Gerberding doesn’t expect “anything to miraculously come into the medicine chest” to impact the sickest patients. “Once people have pneumonia caused by this virus, what’s going on isn’t due to the virus per se... but to the inflammatory response and the damage that creates,” she said. Gerberding hopes to see treatments emerge that prevent severe complications in patients already exposed to the virus. Recovered patients, who are believed to have some immunity to the disease, may offer clues to guide the search for antibody-based coronavirus treatments.
Gerberding concluded with a note of hope and resilience. “It's normal to be concerned and frightened about something this new and potentially this serious,” she said. “Concentrate on how you can protect yourself, how you can prepare yourself and your family, and convert that energy and concern into action, not panic. We can work together to slow down the spread of this virus and I'm confident, based on what I've seen through many outbreaks in the past, that we're up to this as Americans and as global citizens.”
You can watch the video of the full webinar in our eBriefing, "Coronavirus: What You Need to Know".