Date: 06 December 2018
Group B streptococcus (GBS) is a leading cause of serious infection in new born babies and pregnant women. Globally it accounts for the deaths of over 90,000 babies under three months old and causes long-term disability in more than 10,000 neonates, per annum. It is also a major factor in stillbirth and maternal infection. At least 20% of adults carry GBS harmlessly at any time, however pregnant women are much more susceptible to the bacteria and can transmit it to their babies potentially making one, or both of them, very ill.
An NIHR funded trial, sponsored by St George’s University Hospitals NHS Foundation Trust and being delivered with the support of Poole Hospital NHS Foundation Trust, is helping to progress developments for a potential vaccine which could help eradicate GBS in the future. Research midwife, Susara Blunden, is part of the team helping to lead the delivery of the study, known as iGBS, at Poole Hospital.
“We can all be colonised with GBS at some point in our lives. It doesn’t usually cause symptoms or illness in fit, healthy adults so we don’t worry about it. However, it can be really serious for some mums and babies, especially around the time of birth. At Poole, all pregnant women have a urine sample check around 12 weeks, or if they have certain symptoms in pregnancy, they are tested for GBS. If their samples contain GBS or women have had a baby affected by GBS before, we offer antibiotics in labour and additional observations to monitor for signs of infection. Usually this is all that is needed and women and their babies go home happy and healthy.
“Researchers are trying to develop a vaccine for a number of reasons. Firstly, identifying women and babies at risk can be difficult and it is not clear which is the best way to do this in the UK. Secondly, antibiotics in labour don’t always work and only prevent infections that occur in babies’ first seven days. GBS infections in babies older than this aren’t prevented by giving antibiotics, and are more likely to cause meningitis that can lead to developmental problems. If we can provide a vaccine it will protect mums and babies during pregnancy, birth and the postnatal period. The body is really clever; giving a pregnant woman a vaccine results in her producing antibodies which she will pass onto her unborn baby. That’s two people protected from just one vaccine.
“The Paediatric Infectious Diseases Research Group at St George’s, University of London, is hoping that a GBS vaccine will be licensed in the near future but what they need to know, and the aim of the iGBS study, is the level of antibodies a pregnant woman needs to produce in order to provide protection for herself and her baby against GBS. Some women are colonised with GBS around the time of birth but previous sensitising events have produced enough antibodies to protect themselves and their baby against the disease. We often don’t know about these women because they are not symptomatic and the transient nature of GBS means it hasn’t been present in any samples they have provided in pregnancy. It’s currently not practical to test labouring women for GBS as it takes days to get results back and so the opportunity to give antibiotics will have passed.
“We’re asking all mothers if they are happy to donate up to a teaspoon of cord blood after the cord has been cut. It doesn’t affect women having delayed cord clamping or delivering their placenta physiologically. From this blood sample,the research team can measure the level of antibodies mothers have passed onto their babies.
“The majority of women we talk to are really happy to be involved in the study and so far we’ve recruited 600 women since mid-July. We spend most of the morning on the wards, talking to and screening women for eligibility. If they’re interested, we give them an information sheet and time to consider the study. We go back later to see if they’d like to be involved.
“There are several maternity based studies running at Poole so people are used to research and are really receptive to hearing about it. We’ve tried hard to make our research studies visible by using bright colours and bold posters to make them stand out! Even some of the women who decline to take part in one particular study are always interested in hearing about other research we’re doing.
“Everyone is so helpful when it comes to promoting research; we couldn’t ask for better backing. The midwives who work in our birthing suite and labour ward are amazing at notifying us of anyone who might be suitable, and with this approach finding participants is easier. They are also supporting us by collecting samples after a birth. Biochemistry and microbiology help process samples and flag up cases of GBS. We then approach affected families to see if they are happy to provide additional samples. With this study in particular, everyone is very aware of the impact of GBS and is happy to play their part.
“We’re currently the only hospital outside the M25 area to take part in this feasibility study and we are proud of this. We are also the highest recruiting hospital! Dr Latha Vinayakarao, our principal investigator at Poole, and myself, attended a steering committee meeting at St George’s in October. We appraised data collected so far and analysed how to improve recruitment and data integrity for a national study, which we hope that Poole and other local hospitals will be part of.
“A vaccine is a while in the future but we’re definitely at the beginning of something that’s got a lot of potential. In the UK, we’re privileged to have the NHS, with healthcare professionals, antibiotics, IV equipment and labs where we can test for GBS. GBS can be devastating even with all of this and worse in countries without nearby, affordable healthcare or access to antibiotics.
“Research is so important. It’s making the future happen in a better and safer way. It’s safeguarding the health and happiness of your family and future generations. If we can do research well, we can reduce not only the health burden of the nation but reduce the costs within the NHS because a healthier population has less long-term health needs. If you’re poorly, you’d want someone to make sure they knew everything they possibly could about your condition. That’s what research does. Within the next couple of years, I hope that the importance of this research is widely recognised and that more funding is available. By doing research, we’re safeguarding the future."
iGBS feasibility study is funded by the NIHR Evaluation, Trials and Studies Coordinating Centre and sponsored by St George’s University Hospitals NHS Foundation Trust.
Find out more about public health research in Wessex by viewing the latest issue of VISION magazine.
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