COVID-19, the disease caused by SARS-CoV-2, the novel coronavirus first reported in China on Dec. 31, 2019, has quickly become a global concern, grabbing headlines, necessitating quarantines, and disrupting travel and commerce. Here’s what emergency physicians need to know about the epidemic.

The first cases of COVID-19 clustered around a “wet market” in Wuhan, Hubei province. Since then, more than 110,000 cases have been reported in more than 80 countries, though the majority of them are in China.¹

The first reported U.S. COVID-19 cases have largely followed the early distribution models based on air traffic from Hubei province, clustering in major transport hubs like Los Angeles, New York, and Chicago.^1,2 What we know of the epidemiology, pathophysiology, and best approaches to management of COVID-19 relies heavily on what we’ve learned from past outbreaks. As public health and infectious disease specialists scramble to understand a novel viral disease with international implications, emergency and other frontline health care workers need accurate information to prepare their departments for the possibility of encountering patients infected with the virus.

Background and Public Health

If all of this seems reminiscent of the 2003 SARS coronavirus outbreak, that’s because it is. Both outbreaks started with small outbreaks of a severe respiratory disease within fairly isolated Chinese populations, which then escalated rapidly to involve large numbers of patients throughout the region, eventually spreading to far-flung nations along busy commerce and tourism aviation routes.³

The initial Chinese government response to SARS was characterized by efforts to minimize its severity and to avoid public scrutiny. This strategy resulted in a delayed international response and further spread of the disease.³ Despite controversy surrounding potential suppression of early reports of a novel coronavirus in late December 2019, the Chinese public health response to COVID-19 stands in stark contrast with the SARS outbreak.⁴ Rather than months of suppression, the decision to report the virus to World Health Organization authorities within days enabled an early, robust international response and facilitated genetic sequencing of the virus, potentially fast-tracking efforts to discover effective antiviral therapies and vaccines.⁵

Specific efforts to contain the disease and decrease its spread implemented during both the SARS outbreak and the current COVID-19 outbreak include instituting quarantines, closing borders, restricting air and sea travel, and closing local markets thought to contribute to animal-human disease transmission.^6,7