A group from National Institute of Metrology, Beijing, China, etc. has reported characteristics of antibody responses in COVID-19 asymptomatic individuals.
https://www.nature.com/articles/s41392-021-00596-2
Over 40% of individuals undergo asymptomatic infection without showing any symptoms. It is considered that these asymptomatic individuals can efficiently transmit viral infection accounting for more than 30% of virus infection
A total of 143 asymptomatic individuals with SARS-COV-2 were recruited in the study. The viral loads of SARS-CoV-2 based on N gene in saliva peaked at Day 9 of the first detection (315.1 copies/mL, 95% CI 238.1–417.1), followed by gradual decrease and from Day 21 detection was below the cut-off value (102 copies/mL) in a figure below. The positive rate of SARS-CoV-2 detection showed the same trend with the viral loads.
It is found that the antibody responses are short-lived lasting only about 69 days.
