, results of a study show.
From 2010 to 2015, researchers collected data from a cohort study of full-term infants born at Kaiser Permanente of Northern California. “We estimated the effectiveness of maternal pertussis vaccination for protecting newborns against pertussis in the first 2 months of life and in the first year of life, accounting for each infant DTaP dose,” said Roger Baxter, MD, and his associates at Kaiser Permanente Vaccine Study Center, Oakland, Calif.
Among 148,981 newborns, the vaccine effectiveness of maternal Tdap was 91% during the first 2 months of life and 69% during the entire first year of life.The vaccine effectiveness was an estimated 88% before infants had any DTaP vaccine doses, 81% between doses 1 and 2, 6% between doses 2 and 3, and 66% after infants had 3 DTaP doses.
“This result is consistent with 2 earlier studies in the United Kingdom” showing protection in infants less than 3 months of age, and a U.S. study showing maternal Tdap vaccination conferring protection to infants in the first 8 weeks of life, the researchers said.
In conclusion, even after infant DTaP dosing, there was evidence of additional protection from maternal Tdap vaccination for the first year of life (Pediatrics. 2017 Apr 3. doi: 10.1542/peds.2016-4091).