inclusion criteria: 1. both male and female adults aged 18 and above who can provide identification; 2. know the contents of the informed consent form and the situation of the vaccination, sign the informed consent form voluntarily, and have the ability to use the thermometer, scale and fill in the diary card and contact card as required; 3. ability to communicate well with researchers, understand and comply with the requirements of the study; 4. two or three doses of covid-19 inactivated vaccine have been completed and ≥6 months have passed since the last dose of covid-19 inactivated vaccine; 5. healthy subjects or subjects with mild underlying diseases \[stable condition with no worsening condition (no need for hospitalization or no major adjustment in treatment regimen, etc.) for at least 3 months prior to inclusion in the study\]; 6. women who are not possibility to have children (amenorrhea for at least 1 year or surgical sterilization with medical records) or who are known not to be pregnant or lactating and who have used effective contraception for nearly 14 days before vaccination (e.g., intrauterine or implantable contraceptive devices,oral contraceptives, injected or embedded contraceptives, slow-release topical contraceptives, intrauterine devices (iud), condoms (male), diaphragm, cervical cap, etc.) (provide negative proof of pregnancy within 48 hours); 7. sars-cov-2 etiology test (rt-pcr) was negative within 48 hours.

inclusion criteria: 1. both male and female adults aged 18 and above who can provide identification; 2. know the contents of the informed consent form and the situation of the vaccination, sign the informed consent form voluntarily, and have the ability to use the thermometer, scale and fill in the diary card and contact card as required; 3. ability to communicate well with researchers, understand and comply with the requirements of the study; 4. two or three doses of covid-19 inactivated vaccine have been completed and ≥6 months have passed since the last dose of covid-19 inactivated vaccine; 5. healthy subjects or subjects with mild underlying diseases \[stable condition with no worsening condition (no need for hospitalization or no major adjustment in treatment regimen, etc.) for at least 3 months prior to inclusion in the study\]; 6. women who are not possibility to have children (amenorrhea for at least 1 year or surgical sterilization with medical records) or who are known not to be pregnant or lactating and who have used effective contraception for nearly 14 days before vaccination (e.g., intrauterine or implantable contraceptive devices,oral contraceptives, injected or embedded contraceptives, slow-release topical contraceptives, intrauterine devices (iud), condoms (male), diaphragm, cervical cap, etc.) (provide negative proof of pregnancy within 48 hours); 7. sars-cov-2 etiology test (rt-pcr) was negative within 48 hours.

inclusion criteria: both male and female adults aged 18 and above who can provide identification; know the contents of the informed consent form and the situation of the vaccination, sign the informed consent form voluntarily, and have the ability to use the thermometer, scale and fill in the diary card and contact card as required; ability to communicate well with researchers, understand and comply with the requirements of the study; two or three doses of covid-19 inactivated vaccine have been completed and ≥6 months have passed since the last dose of covid-19 inactivated vaccine; healthy subjects or subjects with mild underlying diseases [stable condition with no worsening condition (no need for hospitalization or no major adjustment in treatment regimen, etc.) for at least 3 months prior to inclusion in the study]; women who are not possibility to have children (amenorrhea for at least 1 year or surgical sterilization with medical records) or who are known not to be pregnant or lactating and who have used effective contraception for nearly 14 days before vaccination (e.g., intrauterine or implantable contraceptive devices,oral contraceptives, injected or embedded contraceptives, slow-release topical contraceptives, intrauterine devices (iud), condoms (male), diaphragm, cervical cap, etc.) (provide negative proof of pregnancy within 48 hours); sars-cov-2 etiology test (rt-pcr) was negative within 48 hours.

inclusion criteria: both male and female adults aged 18 and above who can provide identification; know the contents of the informed consent form and the situation of the vaccination, sign the informed consent form voluntarily, and have the ability to use the thermometer, scale and fill in the diary card and contact card as required; ability to communicate well with researchers, understand and comply with the requirements of the study; two or three doses of covid-19 inactivated vaccine have been completed and ≥6 months have passed since the last dose of covid-19 inactivated vaccine; healthy subjects or subjects with mild underlying diseases [stable condition with no worsening condition (no need for hospitalization or no major adjustment in treatment regimen, etc.) for at least 3 months prior to inclusion in the study]; women who are not possibility to have children (amenorrhea for at least 1 year or surgical sterilization with medical records) or who are known not to be pregnant or lactating and who have used effective contraception for nearly 14 days before vaccination (e.g., intrauterine or implantable contraceptive devices,oral contraceptives, injected or embedded contraceptives, slow-release topical contraceptives, intrauterine devices (iud), condoms (male), diaphragm, cervical cap, etc.) (provide negative proof of pregnancy within 48 hours); sars-cov-2 etiology test (rt-pcr) was negative within 48 hours.