Most health authorities are recommending a 14-day quarantine period for those who are at high risk of SARS-CoV-2 infection, the novel coronavirus that causes COVID-19 disease. But is that long enough to identify whether someone has the virus? A new analysis published Mar. 10 by Johns Hopkins Bloomberg School of Public Health researchers says yes.
Their study analyzed 181 cases identified between Jan. 4 and Feb. 24 from those outside Hubei province, China, where the pandemic originated, and resulted in an estimate of 5.1 days for the median disease incubation period.
“Based on our analysis of publicly available data, the current recommendation of 14 days for active monitoring or quarantine is reasonable, although with that period some cases would be missed over the long-term,” says Justin Lessler, an associate professor in the Bloomberg School’s Department of Epidemiology and senior author of the study.
The study, published Mar. 9 in Annals of Internal Medicine, indicates that 97.5 percent of those who develop symptoms of novel coronavirus infection will do so within 11.5 days of infection.
“These estimates imply that, under conservative assumptions, 101 out of every 10,000 cases (99th percentile, 482) will develop symptoms after 14 days of active monitoring or quarantine,” the authors state.
An accurate estimate of COVID-19 onset will help public health authorities in monitoring and controlling the spread of the illness, they add.