WHO has consistently reported the incubation period of COVID-19 — the time between when a person is infected and the onset of symptoms — as anywhere from one to 14 days. A new analysis of 99 COVID-19 case studies has narrowed down the pooled estimate of the mean incubation period as 6.38 days.
Knowing the duration of the incubation period is crucial for detection, isolating infected cases, contact tracing, managing outbreaks and establishing public health programs.
The study showed that COVID-19 seems to be most contagious around the time of symptom onset and infectivity rapidly decreases thereafter to near-zero after approximately 10 days in mild-to-moderately ill patients and 15 days in severely-critically ill and immunocompromised patients.
A quarantine period of at least 10 days would be necessary to limit the transmission of the virus from exposed cases, helpful information for establishing quarantine and isolation guidelines as well as for places like schools, cruise ships and group homes.
SOURCE: International Journal of Infectious Diseases February 2, 2021