The incubation period of 2019-nCoV infections among travellers from Wuhan, China

Currently, a novel coronavirus 2019-nCoV causes an outbreak of viral pneumonia in Wuhan, China. Little is known about its epidemiological characteristics. Using the travel history and symptom onset of 88 confirmed cases that were detected outside Wuhan, we estimate the mean incubation period to be 6.4 (5.6 – 7.7, 95% CI) days, ranging from 2.1 to 11.1 days (2.5 ^th to 97.5 ^th percentile). These values help to inform case definitions for 2019-nCoV and appropriate durations for quarantine.