On December 31, 2019, a cluster of cases of a viral respiratory illness subsequently known as coronavirus disease 2019 (COVID-19) was identified in Wuhan, China. Since that time, according to latest reports from the World Health Organization (WHO), more than 99,000 cases and 3,400 deaths have been reported. The virus has spread to 90 countries. While only about 15% of cases have occurred outside of China, large outbreaks have occurred in South Korea, Japan, Singapore, Iran, and Italy. Pediatric cases have been rare.

COVID-19 is caused by a coronavirus related to the viruses that cause severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), but the fatality rate of COVID-19 appears to be considerably lower than that of either SARS or MERS. Known as SARS-CoV-2, the coronavirus that causes COVID-19 is transmitted via respiratory droplets. The incubation period is estimated to be two to 14 days, according to the Centers for Disease Control and Prevention (CDC). In patients hospitalized with COVID-19 pneumonia, the most common symptoms have included fever, fatigue, dry cough, myalgia, and dyspnea. In an early case series, published online February 7 in JAMA, 26% of 138 hospitalized patients required admission to critical care. Treatment is supportive; antivirals and other drugs have not improved COVID-19 outcomes.

At the time of this writing, the risk of acquiring COVID-19 in much of the United States remains low. A total of 164 cases of COVID-19 and 11 deaths have been reported by the CDC. Those at highest risk are persons who have been exposed to a confirmed case of COVID-19, including health care workers caring for these patients. The CDC does not recommend wearing face masks for protection from any respiratory disease, including COVID-19, unless caring for a patient with COVID-19 in a health care setting or at home.

The CDC has posted extensive information about COVID-19 for both health care professionals and the general public, including case definitions, laboratory testing protocols, infection prevention and control measures, and travel restrictions, at http://www.cdc.gov/coronavirus/2019-nCoV/index.html. The epidemic is evolving rapidly, and information on the site is updated frequently.

For more timely updates, see our blog, Off the Charts, at http://ajnoffthecharts.com.-Betsy Todd, MPH, RN, clinical editor