Children in the United States today receive vaccines to prevent 14 different infections in the first few years of life. This can mean as many as 27 inoculations during that period and as many as five shots at one time. Some parents worry, reasonably, that this represents an assault on the child’s immune system. They worry that children’s immune systems can be weakened or overwhelmed or perturbed.

To address this issue, Jason Glanz and coworkers performed an interesting epidemiological study (Glanz J, Newcomer SR, Daley MR, et. al. Association between estimated cumulative vaccine antigen exposure through the first 23 months of life and non-vaccine targeted infections from 24 through 47 months of age. JAMA. 2018 Mar 6;319(9):906-13). They reasoned that if children’s immune systems were weakened by vaccination, then those children should experience a greater number of non-vaccine targeted infections. To answer this question, they examined 193 children who had non-vaccine targeted infections between 24 through 47 months of age and compared them with 751 control subjects who didn’t have non-vaccine targeted infections. Infections included upper and lower respiratory infections and gastrointestinal infections. Was the group that suffered the non-vaccine targeted infections more likely to have been vaccinated (as determined by the number of vaccine antigens received in the first two years of life) than the group that didn’t suffer these infections? The answer was no. The non-vaccine infection group had received 240 vaccine antigens and the group without such infections, 243 vaccine antigens — an insignificant difference.          

The study by Glanz and coworkers represents yet another piece of evidence that the immunological challenge from vaccines in the first two years of life does not weaken a child’s immune system. Quite the opposite. By allowing children to become immune to diseases that can cause significant suffering, vaccines strengthen their immune systems.

Materials in this section are updated as new information and vaccines become available. The Vaccine Education Center staff regularly reviews materials for accuracy.

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