Abstract:

Objective To evaluate the formation of severe acute respiratory syndrome coronavirus 2（SARS-CoV-2） IgM,IgG and neutralizing antibodies of the adult population who injected with the vaccine of SARS-CoV-2. Methods A total of 80 adults who received the vaccine of SARS-CoV-2（vaccination group） were enrolled,and the serum levels of SARS-CoV-2 IgM,IgG and neutralizing antibodies were determined within 7 d and 14 d after the completion of vaccination. Totally,80 healthy adults who did not receive the vaccine of SARS-CoV-2 were enrolled as control group. They were classified according to age and sex. Results On the 14th day after the completion of vaccination,the positive rate of SARS-CoV-2 IgM,IgG and neutralizing antibodies of vaccination group were 37.5%,98.8% and 95.0%,respectively. The false-positive rate of IgM or IgG antibody was 3.8%,and the false-positive rate of neutralizing antibody was 8.8%. The positive rate of SARS-CoV-2 neutralizing antibody in males was higher than that in females（P<0.05）. There was no statistical significance in the positive rates of the 3 antibodies between those aged 20 to 39 and those aged 40 to 60 in vaccination group（P>0.05）. The serum SARS-CoV-2 IgG antibody level on the 14th day of vaccination was higher than that within 7 d of vaccination（P=0.007）. There was no statistical significance in serum SARS-CoV-2 IgM and neutralizing antibody levels at the 2 time points（P>0.05）. The positive rates of serum SARS-CoV-2 IgG and neutralizing antibodies within 7 d of vaccination were lower than those on the 14th day（P<0.01）. There was no statistical significance between the 2 time points of SARS-CoV-2 IgM antibody（P>0.05）. Conclusions For 2 weeks after adults who completed the SARS-CoV-2 vaccination,the positive rate of SARS-CoV-2 IgG antibody reaches 95.0%,and that of neutralizing antibody reaches 86.2%.

Key words: Severe acute respiratory syndrome coronavirus 2, Vaccination, Severe acute respiratory syndrome coronavirus 2 neutralizing antibody