Pregnant women have even more reason to get a flu shot this year with evidence mounting that it will also benefit their baby.
Results of a North American study just published in the June edition of the American Journal of Public Health found second or third-trimester H1N1 (swine flu) vaccination was associated with improved foetal and neonatal outcomes during the recent pandemic.
These included a reduced risk of pre-term birth at less than 32 weeks, small-for-gestational-age neonates and foetal death, although the study authors said the results were preliminary and more research was required.
A new Australian study will test the effectiveness of the vaccine in protecting babies of vaccinated mothers from flu.
Telethon Institute for Child Health Research Vaccine Trials Group director Peter Richmond said the four-year FluMum study, a large-scale trial involving 10,000 pregnant women nationally, including about 1000 from WA, had just started recruiting.
The study will investigate whether the babies of vaccinated mothers are less likely to get flu than the babies of mothers who did not and also measure how long any protection may last.
Professor Richmond said other studies looking at cord blood had already demonstrated that flu antibodies did pass from the mother into the baby.
"The missing link is knowing how long does that effect last for and how much protection does it give," he said.
"In Australia now we have had a recommendation for some time about vaccinating mums in pregnancy on the basis of protecting the mother and, really, the idea of the FluMum study is we wanted to demonstrate the benefit for the baby in preventing them being hospitalised or them developing influenza in that first six months."
Professor Richmond said this theory might also translate for the babies of mothers vaccinated against other diseases including whooping cough and pneumococcal disease.
Small studies had shown that, similar to influenza, babies born to mothers vaccinated with the whooping cough vaccine had high levels of antibodies.
"We do think that this may be a good way to protect very young babies who are maybe too young to benefit from the vaccine- produced protection so I think we will see more in this space - maybe even for pneumococcal disease," he said.
Professor Richmond said the H1N1 pandemic had reinforced that pregnant mothers were at risk of serious flu complications, with a large number of mothers admitted to hospital.
"I think pregnant mums do tend to think more about their babies rather than themselves so it is important to get this message out there that it is to the benefit of both of them," he said.
First-time mum Melissa O'Donnell, 36, who is due this week, had the flu shot in April after her obstetrician told her it could benefit her baby.
"I checked with my obstetrician whether it was a good idea to have it and he said that new research is emerging to say it would be good for my baby up until six months of age, that he would be protected from the flu," she said.
"Then when I saw the information about the study, I thought I'd really like to know whether the decision I made was the right one."
All pregnant women are eligible to receive a free flu vaccine and it is recommended for women in their second or third trimester.
The FluMum study is recruiting women who have had their baby in the past eight weeks or who are due in the next four months. Participants will be asked to answer questions over the phone.
To find out more about the FluMum trial, phone 9340 8542 or email email@example.com.