Abstract
Objective: The ongoing COVID-19 pandemic warrants accelerated efforts to test vaccine candidates. To explore the influencing factors on vaccine-induced effects, antibody responses to an inactivated SARS-CoV-2 vaccine in healthy individuals who were not previously infected by COVID-19 were assessed.
Methods: All subjects aged 18-60 years who did not have SARS-CoV-2 infection at the time of screening from June 19, 2021, to July 02, 2021, were approached for inclusion. All participants received two doses of inactivated SARS-CoV-2 vaccine. Serum IgM and IgG antibodies were detected using a commercial kit after the second dose of vaccination. A positive result was defined as 10 AU/mL or more and a negative result as less than 10 AU/mL. This retrospective study included 97 infection-naïve individuals (mean age 35.6 years; 37.1% male, 62.9% female).
Results: The seropositive rates of IgM and IgG antibody responses elicited after the second dose of inactivated SARS-CoV-2 vaccine were 3.1% and 74.2%, respectively. IgG antibody levels were significantly higher than IgM levels (P<0.0001). Sex had no effect on IgM and IgG antibody response after the second dose. The mean anti-IgG level in older persons (⩾42 years) was significantly lower than that of younger recipients. There was a significantly lower antibody level at > 42 days compared to that at 0-20 days (P<0.05) and 21-31 days (P<0.05) after the second dose.
Conclusion: IgG antibody response could be induced by inactivated SARS-CoV-2 vaccine in healthy individuals (>18 years), which can be influenced by age and detection time after the second dose of vaccination.
Keywords: COVID-19; IgM and IgG antibody responses; inactivated SARS-CoV-2 vaccine.
【저자키워드】 COVID-19, IgM and IgG antibody responses, inactivated SARS-CoV-2 vaccine., 【초록키워드】 IgM, vaccination, antibody, SARS-COV-2 infection, COVID-19 pandemic, Antibody Response, SARS-CoV-2 vaccine, Retrospective study, Antibody responses, IgG antibody, IgG antibodies, male, female, age, seropositive, inactivated, dose, IgM and IgG, no effect, Older, Factor, dose of vaccination, recipients, subject, second dose, All participants, healthy individuals, all subjects, individual, positive result, effort, vaccine candidates, significantly lower, Effects, anti-IgG, defined, less, significantly higher, had no, elicited, accelerated, in healthy individual, All participant, for inclusion, were assessed, 【제목키워드】 SARS-CoV-2, Human, response, IgM and IgG,