A large US study is the first to provide strong evidence that vaccinating expecting mothers against pertussis protects their newborns.
Data from nearly 150,000 newborns born between 2010 to 2015 showed a 91% efficacy of a maternal vaccine during the first two months of life – a crucial period since babies are only vaccinated at two months.
In the study, of 17 cases of pertussis recorded in the first two months of life, only one involved a newborn whose mother had been vaccinated before birth.
Maternal vaccination continued to protect even after the newborn had been immunised, with a 69% efficacy over the entire first year of life.
The researchers from Kaiser Permanente in Oakland, California, found no evidence of interference between maternal and newborn vaccines.
“The strategy of immunising pregnant women to boost maternal antibody transfer appears to be more effective for protecting young infants against pertussis than are attempts at ‘cocooning’ in which mothers and other persons in close contact with newborns are vaccinated,” they write in the journal Pediatrics.
In Australia, which has one of the highest reported rates of pertussis in the world, the immunisation handbook was updated in 2015 to include a recommendation to vaccinate pregnant women in their third trimester, regardless of their vaccination history.
Although this recommendation, coupled with new funding, significantly boosted vaccination uptake, over a quarter of pregnant women in Australia are still not vaccinated during their pregnancy, report Melbourne researchers writing in the ANZ Journal of Obstetrics and Gynaecology.
The most common reasons for pregnant women not getting vaccinated are that their healthcare provider doesn’t offer it or that they are unaware of the recommendation, the researchers found.
Social media could play a role in boosting vaccination rates in pregnant women, they suggest.