Since early December 2019, several pneumonia cases of unknown aetiology have occurred in Wuhan and rapidly spread throughout China [1,2]. The International Committee on Taxonomy of Viruses (ICTV) has named this virus SARS-CoV-2, and it belongs to the same species as SARS-CoV [3]. Meanwhile, the World Health Organization (WHO) has named the virus-infected pneumonia coronavirus disease 2019 (COVID-19) [4]. As at 5 March 2020, a total of 80,409 COVID-19 cases and 3,012 deaths (3.75%) have been reported in mainland China [5]. The 52,045 recovered cases (64.73%) were further quarantined at home for at least 2 weeks [5]. However, potential infectivity of these recovered cases was still unclear. Thus, we implemented consecutive virus surveillance among medical staff recovered from COVID-19 at our hospital and aimed to investigate their potential infectivity after discharge.