Vaccinating pregnant women against pertussis was shown to be highly effective in protecting newborn infants against the life-threatening respiratory infection, which is also known as whooping cough, according to a new study to be published in the May 2017 issue of Pediatrics.
The maternal Tdap vaccine was 91.4% effective during the infant's first two months of life, and 69% effective during the child's entire first year.
The study, "Effectiveness of Vaccination During Pregnancy to Prevent Infant Pertussis," analyzed records of 148,981 infants born at Kaiser Permanente Northern California from 2010 to 2015.
The study (published online April 3) strongly supports the current U.S. recommendation to administer Tdap during each pregnancy, preferably between 27 and 36 weeks to maximize antibody transfer. Pertussis, caused by a bacteria, Bordetella pertussis, can affect people of any age but is especially virulent and life-threatening in infants.
The strategy of immunizing pregnant women to boost maternal antibody appears to be more effective for protecting young infants than are attempts at "cocooning," in which mothers and other people close contact with newborns are vaccinated.