Epidemiological and clinical characteristics of humans with avian influenza A (H7N9) infection in Guangdong, China, 2013-2017.

•The fatality rate of the 256 confirmed cases was 39.0%, and the proportion of ICU admission was 65.6%.•The proportions of accepting oseltamivir, zanamivir, and peramivir treatment were 83.1%, 13.6%, and 29.6%, respectively.•Earlier oseltamivir and zanamivir treatment were negatively associated with the death of A (H7N9) infected patients.•Time from illness onset to confirmation and oseltamivir treatment were positively related to ICU admission.