Procedures
redness, nausea, itching, swelling, fever, cellulitis, muscle ache, fatigue, pain, headache
ADVERSE REACTIONS, ADVERSE EVENTS, CELLULITIS, ADVERSE EVENT, INDURATION, MAY, EVENTS
In May 2022, 200 eligible participants received one dose of Ad5-nCoV or inactivated vaccine via intramuscular injection. The variety of the fourth dose of inactivated vaccine was the same as that used for the pre-received third dose. After the booster vaccination, all participants were monitored for 30 min for any immediate adverse reactions and instructed to record adverse events for the next 14 days on a participant diary card. Solicited injection site events included pain, redness, swelling, induration, itching, and cellulitis, while systemic events included fever, malaise, muscle ache, joint pain, fatigue, nausea, and headache. Unsolicited adverse events within 28 days were also reported by the participants and recorded. Serious adverse events (SAEs) self-reported by participants were documented throughout the study. Adverse events were graded as mild (grade 1), moderate (grade 2), severe (grade 3), or life-threatening (grade 4), according to the scale issued by the China State Food and Drug Administration (version 2019), and the causality with immunization was estimated before unmasking.To assess the presence of anti-SARS-CoV-2 antibodies, a 10-ml blood sample was collected from each participant at baseline before they received the booster dose and 14, 28, and 90 days after receiving the booster dose. The quantitative measurement of wild-type SARS-CoV-2 RBD-specific IgG responses was performed using the commercial Anti-SARS-CoV-2 RBD-IgG ELISA kit (Vazyme Medical Technology, Nanjing, China). The lower limit of detection was 1:10, and values below this limit were imputed and defined as 1:10. The positive cutoff values for RBD-specific IgG antibodies were defined as titers of 1:90