Investigation on the loss of protective immunity with hand-foot-mouth vaccine in children of different ages
Objective To investigate the loss of protective immunity with hand-foot-mouth vaccine in children of different ages,with a particular focus on Enterovirus 71(EV71)antibody levels to help better understand the immune status of children.Methods Serum samples were collected from 100 children who underwent health checkups,and their serum levels of EV71 antibodies[immunoglobulin G(IgG)and immunoglobulin M(IgM)]were detected by enzyme linked immunosorbent assay,and the serological detection of EV71 antibody in children of different ages was compared.Results In 100 children,the positive rate of EV71-IgG antibody was 60.0% (60/100)and the positive rate of EV71-IgM antibody was 7.0% (7/100).The positive rate of IgG antibody in both boys and girls was 30.0% (30/100);the positive rate of IgM antibody in boys was 2.0% (2/100),and the positive rate of IgM antibody in girls was 5.0% (5/100).The IgM positive rate was 6.7% (2/30)and IgG positive rate was 50.0% (15/30)in children aged 3-5 years.The IgM positive rate was 6.7% (2/30)and IgG positive rate was 66.7% (20/30)in children aged 5-6 years.The IgM positive rate was 7.5% (3/40)and IgG positive rate was 62.5% (25/40)in children aged 6-7 years.There was no significant difference in the positive rates of IgM and IgG antibodies in children of different age groups(P>0.05).Conclusion Children aged 3-7 years are relatively susceptible to EV71 infection,and this finding underscores the importance of routine prevention efforts for hand-foot-mouth disease(HFMD)in children and the urgency of increasing vaccination rates,which will help to reduce the risk of EV71 infection in children and reduce the incidence of HFMD,thereby safeguarding children's health and public health.
Different agesChildrenHand-foot-mouth vaccineLoss of protective immunity