1) healthy subjects aged 18 and above with full capacity for civil conduct and can provide information on vaccination of completing the 2 doses ChAdOx1 (AZD1222) vaccine or heterologous inactivated covid-19 vaccine/ChAdOx1 (AZD1222) vaccine for at least 3 months. 2) The subjects voluntarily participated in the study, signed informed consent, provided valid identity certificates, understood and complied with the requirements of the test protocol. 3) The subjects agreed to take effective contraceptive measures from the signing of informed consent to 1 month after the vaccination of the trial vaccine.

1) healthy subjects aged 18 and above with full capacity for civil conduct and can provide information on vaccination of completing the 2 doses ChAdOx1 (AZD1222) vaccine or heterologous inactivated covid-19 vaccine/ChAdOx1 (AZD1222) vaccine for at least 3 months. 2) The subjects voluntarily participated in the study, signed informed consent, provided valid identity certificates, understood and complied with the requirements of the test protocol. 3) The subjects agreed to take effective contraceptive measures from the signing of informed consent to 1 month after the vaccination of the trial vaccine.