US Pharm. 2020;45(4):28-32.

Nicholas Reich, associate professor in the University of Massachusetts (UMass) Amherst School of Public Health and Health Sciences, heads a flu forecasting collaborative that has produced some of the world’s most accurate models in recent years. He and postdoctoral researcher Thomas McAndrew have been conducting weekly surveys of more than 20 infectious disease modeling researchers to assess their collective expert opinion on the trajectory of the COVID-19 outbreak in the U.S. The researchers and modeling experts design, build, and interpret models to explain and understand infectious-disease dynamics and the associated policy implications in human populations.

Dr. Reich is coauthor of a new study in the Annals of Internal Medicine that calculates that the median incubation period for COVID-19 is just over 5 days and that 97.5% of people who develop symptoms will do so within 11.5 days of infection. The incubation period refers to the time between exposure to the virus and the appearance of the first symptoms.

The study’s lead author is UMass Amherst biostatistics doctoral alumnus Stephen Lauer, a former member of the Reich laboratory and current postdoctoral researcher at the Johns Hopkins Bloomberg School of Public Health.

The researchers examined 181 confirmed cases with identifiable exposure and symptom-onset windows to estimate the incubation period of COVID-19. They conclude that “the current period of active monitoring recommended by the U.S. Centers for Disease Control and Prevention [14 days] is well supported by the evidence.”