inclusion criteria: * participants who has received prime vaccination of adenovirus type-5 vectored covid-19 vaccine * able to understand the content of informed consent and willing to sign the informed consent * negative in hiv diagnostic test. * axillary temperature ≤37.0°c. * general good health as established by medical history and physical examination. * able to complete 12 months visit

inclusion criteria: * participants who has received prime vaccination of adenovirus type-5 vectored covid-19 vaccine * able to understand the content of informed consent and willing to sign the informed consent * negative in hiv diagnostic test. * axillary temperature ≤37.0°c. * general good health as established by medical history and physical examination. * able to complete 12 months visit

inclusion criteria: - participants who has received prime vaccination of adenovirus type-5 vectored covid-19 vaccine - able to understand the content of informed consent and willing to sign the informed consent - negative in hiv diagnostic test. - axillary temperature ≤37.0°c. - general good health as established by medical history and physical examination. - able to complete 12 months visit

inclusion criteria: - participants who has received prime vaccination of adenovirus type-5 vectored covid-19 vaccine - able to understand the content of informed consent and willing to sign the informed consent - negative in hiv diagnostic test. - axillary temperature ≤37.0°c. - general good health as established by medical history and physical examination. - able to complete 12 months visit