inclusion criteria: 1. healthy adults aged 18 years and older, both male and female, who can provide legal identity certificate of participants; 2. the subject understands the contents of the informed consent form and the vaccination situation of this vaccination, voluntarily signs the informed consent form, and has the ability to use the thermometer, scale and fill in the diary card and contact card as required (if the subject is unable to sign the informed consent form by himself/herself due to limited reading and writing ability, the informed consent form and signature of the informed consent form can be completed under the witness' s witness); 3. able to communicate well with investigators and understand and comply with the requirements of this trial; 4. completion of basic immunization with sars-cov-2 vaccine ≥ 6 months; 5. negative nucleic acid test for sars-cov-2 within 3 days prior to vaccination; 6. women who have used effective contraception within 2 weeks prior to inclusion in this trial, have a negative pregnancy test (pregnancy test can be exempted for those who have been amenorrheic for at least 1 year or have a documented history of surgical sterilization), and voluntarily agree to continue using at least 1 effective contraception within 6 months after vaccination \[effective contraception includes: oral contraceptives, injected or implanted contraception, sustained-release local contraceptives, hormonal patches, intrauterine device (iud), sterilization, abstinence, condoms (men), diaphragms, cervical caps, etc.\]; 7. healthy participants or participants with mild underlying disease \[stable condition without worsening (requiring no hospitalization or major modification of treatment regimen, etc.) for at least 3 months prior to inclusion in this trial\].

inclusion criteria: 1. healthy adults aged 18 years and older, both male and female, who can provide legal identity certificate of participants; 2. the subject understands the contents of the informed consent form and the vaccination situation of this vaccination, voluntarily signs the informed consent form, and has the ability to use the thermometer, scale and fill in the diary card and contact card as required (if the subject is unable to sign the informed consent form by himself/herself due to limited reading and writing ability, the informed consent form and signature of the informed consent form can be completed under the witness' s witness); 3. able to communicate well with investigators and understand and comply with the requirements of this trial; 4. completion of basic immunization with sars-cov-2 vaccine ≥ 6 months; 5. negative nucleic acid test for sars-cov-2 within 3 days prior to vaccination; 6. women who have used effective contraception within 2 weeks prior to inclusion in this trial, have a negative pregnancy test (pregnancy test can be exempted for those who have been amenorrheic for at least 1 year or have a documented history of surgical sterilization), and voluntarily agree to continue using at least 1 effective contraception within 6 months after vaccination \[effective contraception includes: oral contraceptives, injected or implanted contraception, sustained-release local contraceptives, hormonal patches, intrauterine device (iud), sterilization, abstinence, condoms (men), diaphragms, cervical caps, etc.\]; 7. healthy participants or participants with mild underlying disease \[stable condition without worsening (requiring no hospitalization or major modification of treatment regimen, etc.) for at least 3 months prior to inclusion in this trial\].

inclusion criteria: healthy adults aged 18 years and older, both male and female, who can provide legal identity certificate of participants; the subject understands the contents of the informed consent form and the vaccination situation of this vaccination, voluntarily signs the informed consent form, and has the ability to use the thermometer, scale and fill in the diary card and contact card as required (if the subject is unable to sign the informed consent form by himself/herself due to limited reading and writing ability, the informed consent form and signature of the informed consent form can be completed under the witness' s witness); able to communicate well with investigators and understand and comply with the requirements of this trial; completion of basic immunization with sars-cov-2 vaccine ≥ 6 months; negative nucleic acid test for sars-cov-2 within 3 days prior to vaccination; women who have used effective contraception within 2 weeks prior to inclusion in this trial, have a negative pregnancy test (pregnancy test can be exempted for those who have been amenorrheic for at least 1 year or have a documented history of surgical sterilization), and voluntarily agree to continue using at least 1 effective contraception within 6 months after vaccination [effective contraception includes: oral contraceptives, injected or implanted contraception, sustained-release local contraceptives, hormonal patches, intrauterine device (iud), sterilization, abstinence, condoms (men), diaphragms, cervical caps, etc.]; healthy participants or participants with mild underlying disease [stable condition without worsening (requiring no hospitalization or major modification of treatment regimen, etc.) for at least 3 months prior to inclusion in this trial].

inclusion criteria: healthy adults aged 18 years and older, both male and female, who can provide legal identity certificate of participants; the subject understands the contents of the informed consent form and the vaccination situation of this vaccination, voluntarily signs the informed consent form, and has the ability to use the thermometer, scale and fill in the diary card and contact card as required (if the subject is unable to sign the informed consent form by himself/herself due to limited reading and writing ability, the informed consent form and signature of the informed consent form can be completed under the witness' s witness); able to communicate well with investigators and understand and comply with the requirements of this trial; completion of basic immunization with sars-cov-2 vaccine ≥ 6 months; negative nucleic acid test for sars-cov-2 within 3 days prior to vaccination; women who have used effective contraception within 2 weeks prior to inclusion in this trial, have a negative pregnancy test (pregnancy test can be exempted for those who have been amenorrheic for at least 1 year or have a documented history of surgical sterilization), and voluntarily agree to continue using at least 1 effective contraception within 6 months after vaccination [effective contraception includes: oral contraceptives, injected or implanted contraception, sustained-release local contraceptives, hormonal patches, intrauterine device (iud), sterilization, abstinence, condoms (men), diaphragms, cervical caps, etc.]; healthy participants or participants with mild underlying disease [stable condition without worsening (requiring no hospitalization or major modification of treatment regimen, etc.) for at least 3 months prior to inclusion in this trial].