To determine the safety and immunogenicity of booster doses of vaccine against SARS-CoV2 after a minimum of 90 days and a maximum of 270 days after the 2nd dose of a homologous 2 dose primary regimen.~It is planned to recruit 111 subjects for 2 vaccines (Turkovac and CoronaVac). There will be a total of 222 subjects.
A booster dose of vaccine (Turkovac or CoronaVac) will be administered to subjects who have passed at least 90 days and at most 270 days after the second dose of the first course of CoronaVac vaccine.