Over 40% of the coronavirus disease 2019 (COVID-19) COVID-19 patients were asymptomatically infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the immune responses of these asymptomatic individuals is a critical factor for developing the strategy to contain the COVID-19 pandemic. Here, we determined the viral dynamics and antibody responses among 143 asymptomatic individuals identified in a massive screening of more than 5 million people in eight districts of Wuhan in May 2020. Asymptomatic individuals were admitted to the government-designated centralized sites in accordance with policy. The incidence rate of asymptomatic infection is ~2.92/100,000. These individuals had low viral copy numbers (peaked at 315 copies/mL) and short-lived antibody responses with the estimated diminish time of 69 days. The antibody responses in individuals with persistent SARS-CoV-2 infection is much longer with the estimated diminish time of 257 days. These results imply that the immune responses in the asymptomatic individuals are not potent enough for preventing SARS-CoV-2 re-infection, which has recently been reported in recovered COVID-19 patients. This casts doubt on the efficacy of forming “herd-immunity” through natural SARS-CoV-2 infection and urges for the development of safe and effective vaccines.
【저자키워드】 immunology, Microbiology, 【초록키워드】 COVID-19, coronavirus disease, SARS-CoV-2, Coronavirus disease 2019, Efficacy, coronavirus, immune response, SARS-COV-2 infection, COVID-19 pandemic, Antibody Response, severe acute respiratory syndrome Coronavirus, Policy, Antibody responses, Asymptomatic individuals, immune responses, Wuhan, asymptomatic infection, Re-infection, incidence rate, viral dynamics, Critical, Recovered COVID-19 patients, COVID-19 patient, Safe, acute respiratory syndrome, acute respiratory syndrome coronavirus, acute respiratory syndrome coronavirus 2, individual, Effective vaccines, doubt, over, asymptomatic individual, reported, peaked, eight, short-lived, viral copy number, 【제목키워드】 Antibody Response, Asymptomatic,