It looks like there's an issue with children.
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"The results reveal that antibiotic use is associated with lower antibody levels to several vaccine antigens and a frequency-dependent effect of antibiotic courses over time in the first 2 years of life," the authors wrote.
In a video abstract that accompanies the study, senior author Michael Pichichero, MD, of Rochester General Hospital Research Institute says that while the study is small and limited to children in one city, the findings nonetheless further highlight the need for careful use of antibiotics in children.
"This is new information for pediatricians, and yet again more reason for judicious antibiotic prescribing," Pichichero said.
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a tip of the hat to Sukie