Safety and Immunogenicity of the Third and Fourth Doses of Vaccine Against SARS-CoV-2 Following a 2-Dose Regimen of Inactivated Whole-Virion SARS-CoV-2 Vaccine

Investigators determined the seroconversion rate of neutralizing antibodies against wild-type SARS-CoV-2 and VOCs at day 28 after the third dose of vaccine and day 28 after the fourth dose of vaccine.