New research indicates that human immune responses to vaccines vary with the seasons, showing stronger antibody production during winter months in temperate regions. The findings come from an analysis of dozens of clinical trials involving children worldwide.
Researchers combined results from 96 randomised controlled trials that included around 48,000 children vaccinated against 14 different infections. In temperate areas of both hemispheres, antibody responses peaked in winter, consistent with changes in day length. Near the equator the pattern was more variable and depended on the specific vaccine.