Compelling research shows immunising pregnant mums protects babies from whooping cough
Whooping cough remains an all too common preventable disease in New Zealand and epidemics continue to occur. Fully
immunised infants get their best protection by the age of 6 months, leaving a wide window of opportunity to catching
this nasty disease in the first few weeks and months of life. At this age they are particularly vulnerable to severe
disease; for every seven infants who catch whooping cough, at least one will end up in hospital. Tragically too, four
infants have died in the past two years from complications associated with whooping cough.
“It is heartbreaking to watch a young infant cough uncontrollably with this awful disease. It causes a prolonged bad
cough, which can go on to pneumonia, brain inflammation and bleeding from excessive coughing. Whooping cough is a very
dangerous disease, particularly for young infants. The earliest infants can be vaccinated is from 6 weeks of age, then
at 3 and 5 months. Before five months they are at risk of this highly infectious disease.
Since 2012 The Ministry of Health has funded the immunisation of pregnant mums, as they pass some of their protective
antibodies onto their infant through the placenta. This may protect the new baby for the first and most vulnerable few
weeks of life. Newly published research in the Lancet has taken this one step further and demonstrates the first
estimates of the effectiveness of a maternal
pertussis vaccination programme in prevention of infant disease.
In this large British study that included 26,684 women and their infants there were significantly fewer cases of
whooping cough in infants born to mothers who received a booster vaccination during the latter stages of their
pregnancy. The vaccine was over 90% effective in preventing whooping cough in infants during their first few months of
life.
Dr Helen Petousis-Harris, Director of Research at the Immunisation Advisory Centre notes “We have research showing that
babies receive some maternal antibodies from their mum before birth.
But until this we had only indirect evidence that this protected the baby from actually acquiring whooping cough. These
findings show that maternal immunisation with an acellular-pertussis-containing vaccine can provide over 90% protection
against infant disease. This is the first time that this protection has been shown.”
The University of Auckland is currently undertaking an HRC funded study on the effectiveness of maternal vaccination
with pertussis vaccine and the results will be available in 2015. Principal investigator Helen Petousis-Harris says the
New Zealand study will complement the British study as it uses different methods.
This new study and the growing body of safety data shows that maternal immunisation against this disease is one of the
best strategies we currently have against severe whooping cough disease in our youngest infants.
ends