To verify reliability of antibody detection and investigate population immunity to severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) in the local Chinese population . A cross-sectional study was conducted in Shenzhen to detect anti-coronavirus antibodies including, immunoglobulin G (IgG), immunoglobulin M (IgM), and immunoglobulin A (IgA). In the COVID-19 group, nine patients were enrolled after diagnosis . In the control group, 1589 individuals without clinical symptoms (cough, fever, and fatigue) and returning from outside Shenzhen were enrolled . The first study enrollment occurred at the end of February 2020; the final study visit was 18 March 2020 . In the COVID-19 group, the seven of nine patients were positive for IgM, IgG, and IgA . Meanwhile, six of the 1589 healthy individuals were found to be weakly positive for IgG . According to SARS-CoV-2 nucleic acid tests, the six individuals were all negative . Strong supplemental support for clinical information can be provided by antibody detection, especially for IgA . According to comparison with overseas reports, the infection rate of the Chinese population outside Shenzhen, China, is significantly low, so most of the population in China is still susceptible . Hence, social distancing measures are still inevitable until a vaccine is developed successfully.