2017 has been Australia鈥檚 worst flu season on record, with infants, children and the elderly the most vulnerable to the influenza virus. According to Dr Annette Regan, whose award-winning research focuses on maternal child health, it鈥檚 critical for pregnant women to get the flu vaccine and pertussis (whooping cough) vaccine to protect themselves and their unborn children from potentially fatal illnesses, a practice known as 鈥榤aternal immunisation鈥�.
Whooping cough and flu vaccines are free for pregnant women.
The health impacts of influenza and whooping cough are often underestimated, however both viruses can cause debilitating complications, or even death, in vulnerable populations. Vaccinating a pregnant woman against the viruses both the mother and her unborn child. The mother will develop antibodies in response to the vaccines, which protect her from infection, and she will transfer these antibodies to her baby via her placenta. Her baby is then protected until s/he is old enough to be immunised. This protection has been described as the 鈥榰ltimate birthday gift鈥� from a mother to her child.
鈥淲hen pregnant your immune system is slightly depressed, so if you get an infection it tends to be much more severe and that is very likely to impact on the unborn baby,鈥� says Regan.
鈥淧regnant women and their infants are at high risk of serious complications from respiratory infections like influenza. For this reason, influenza and pertussis vaccines are currently recommended during every pregnancy.
鈥淚nfluenza vaccines can be given at any time during pregnancy, and pertussis vaccine is given between 28 and 32 weeks of pregnancy. These vaccines not only protect the mother against infection, but they also prevent serious infections in their infants in the first months of life.鈥�
Maternal vaccination can prevent babies from becoming fatally ill.
Perhaps one of the most high-profile victims of whooping cough is Perth-born baby . In 2015, at three weeks of age, Riley contracted what appeared to be a cold, but was in fact whooping cough. Riley was quickly hospitalised at Princess Margaret Hospital, but developed pneumonia and, despite treatment, tragically died at four weeks of age.
Two days after Riley鈥檚 death, the Western Australian State Government launched a program for pregnant women to access free pertussis booster shots in their third trimester of pregnancy. (Free booster shots are now available for pregnant women in all Australian states and territories, as are flu vaccines.) Riley鈥檚 parents, Catherine and Greg Hughes, went on to establish the , and campaign and advocate for the importance of vaccines for pregnant women and the National Immunisation Program Schedule for infants and children.
Why don鈥檛 pregnant women vaccinate?
Despite the availability of free flu and whooping cough vaccines for pregnant women, and the documented safety of these vaccines, the biggest barrier to maternal vaccination is a lack of guidance from treating healthcare professionals.
鈥淏y far the biggest factor influencing whether a woman will get vaccinated during pregnancy or not, is whether her healthcare provider recommends it to her. Nearly 80 per cent of women say they would be vaccinated if their provider had recommended it to them,鈥� says Regan.
鈥淭here is also sometimes a perception that vaccination is not necessary, as women are not always aware of the severity of these diseases 鈥omen also cite concerns about the safety of the vaccine to their baby, and possible side effects, as a reason why they choose not to be vaccinated.鈥�
The biggest barrier to maternal vaccination is a lack of guidance from treating healthcare professionals.
Vaccines can be a fraught topic amongst some members of the community, who believe vaccinations can cause health issues, or developmental differences, such as Autism Spectrum Disorder, in infants or children. There are no credible studies to support the idea that vaccinations can cause health issues or developmental differences in infants and young children, and vaccines are known to be protective of both the mother and baby鈥檚 health, as Regan鈥檚 research demonstrates.
鈥淭here are unfortunately some anti-vaccine groups who believe that vaccination during pregnancy is not safe and is associated with birth defects, like microcephaly. This is simply not true, as there have been numerous studies showing that both influenza and pertussis vaccines are safe to mothers and their infants,鈥� Regan says.
鈥淚n fact, some studies have shown babies may be healthier if born to vaccinated mothers 鈥� one of my PhD studies showed that influenza vaccination during pregnancy may reduce the risk of stillbirth.鈥�
Regan鈥檚 PhD study, , which combined data sources from 60,000 births in Western Australia between 2012 and 2013, showed that pregnant women who had a flu vaccine had half the risk of stillbirth compared to unvaccinated women. The study garnered national attention, and resulted in an increase in maternal immunisation.
鈥淭he results received a lot of media attention, and were publicized through social media. Several women in parenting blogs like Mama Mia and on the page left comments stating they had booked their influenza vaccine because they heard of the study. Given less than two-thirds of women receive an influenza vaccine each year, encouraging more women to get vaccinated is a fantastic result,鈥� she says.
Regan was awarded the prestigious Aileen Plant Memorial Prize in Infectious Disease Epidemiology in 2017 for her PhD research.
One eye on the future
Up until 2015, when Riley Hughes鈥� death proved a catalyst for maternal vaccinations, pregnant women did not widely receive either flu or whooping cough vaccines, and there is limited data on how these vaccinations impact children鈥檚 health in the long term. Regan, in partnership with a Canadian colleague, Associate Professor Deshayne Fell, University of Ottawa, is currently researching this area.
鈥淎lthough maternal vaccination is not a new idea by any means, until 2015, relatively few pregnant women received these vaccines. As a result, there is little known about the long-term health effects on children,鈥� Regan says.
鈥淒r Fell and myself are starting a study which will look at the long-term health effects of influenza vaccines and pertussis vaccines given during pregnancy on children in Australia and Canada. This area is pretty exciting, as so few studies currently exist.鈥�
In addition to the recommended flu and whooping cough vaccines, more vaccines for pregnant women are currently being developed, including a vaccine for respiratory syncytial virus, a common respiratory virus, which can cause bronchiolitis and pneumonia in infants. Regan is currently researching the impact of the virus on pregnant women, and the results of her work will inform decisions about the value of the vaccine, or otherwise, for pregnant women.
鈥淚鈥檓 currently doing some work with an international network of researchers to identify the clinical importance of respiratory syncytial virus infection during pregnancy. This information will be important for determining whether there is any value of these vaccines for pregnant women in addition to their infants,鈥� she says.
鈥淧ublic health research offers the opportunity to evaluate and inform policies and interventions, which can make a difference in everyday people鈥檚 lives. I most enjoy that the questions my research helps to answer will ultimately be used by prevention programs to promote healthier lives.鈥�
