Co-infection of SARS-CoV-2 and Influenza virus in Early Stage of the COVID-19 Epidemic in Wuhan, China

•Of the 1001 influenza positive samples, 3 outpatients and 1 inpatient were co-infected with SARS-CoV-2 in Wuhan in January, 2020.•Clinical and laboratory features indicate the 3 outpatients showed mild symptoms, and the inpatient experienced malignant tumor and had worse outcomes from COVID-19.•In January, when the testing capacity is insufficient, co-infection of SARS-CoV-2 with influenza viruses in winter influenza activity peak season may contribute the expansion of SARS-CoV-2 in the local population.