Estimated Incubation Period and Serial Interval for Human-to-Human Influenza A(H7N9) Virus Transmission.

We estimated the incubation period and serial interval for human-to-human-transmitted avian influenza A(H7N9) virus infection using case-patient clusters from epidemics in China during 2013-2017. The median incubation period was 4 days and serial interval 9 days. China's 10-day monitoring period for close contacts of case-patients should detect most secondary infections.