There is an urgent need for a vaccine to prevent a bacteria that is a major cause of pre-term births, disability and baby deaths worldwide, experts have said.
A report from the World Health Organisation (WHO) and the London School of Hygiene & Tropical Medicine (LSHTM) reveals the global impact of Group B streptococcus (GBS).
What is Group B streptococcus (GBS)?
It is a common bacterium that can be transmitted in the womb, during birth or in the early weeks of life.
GBS leads to around 150,000 deaths of babies each year, more than half a million pre-term births and significant long-term disability, researchers have found.
WHO researchers say their study is the first to quantify the major contribution of GBS to pre-term births, as well as neurological impairments – such as cerebral palsy, hearing and vision loss.
According to the Group B Strep Support (GBSS) charity, in the UK two babies a day develop GBS, one baby a week dies from the infection, and one baby a week survives with disability.
Dr Phillipp Lambach, medical officer from the WHO’s Immunisation, Vaccines and Biologicals department, and report author, said: “This new research shows that Group B strep is a major and underappreciated threat to newborn survival and wellbeing, bringing devastating impacts for so many families globally".
Can the infection be treated? The new report calls for the urgent development of maternal vaccines against GBS to reduce the high disability and death toll.
The experts say vaccines could be highly cost-effective and have significant health benefits across the world.
“WHO joins partners in calling for urgent development of a maternal GBS vaccine, which would have profound benefits in countries worldwide”, Dr Lambach said.
While several GBS vaccine candidates have been in the pipeline for a number of decades, none are yet available.
Professor Joy Lawn, director of the Maternal Adolescent Reproductive & Child Health (MARCH) Centre at LSHTM, and a contributor to the report, said: “Maternal vaccination could save the lives of hundreds of thousands of babies in the years to come, yet 30 years since this was first proposed, the world has not delivered a vaccine.
How can vaccines help?
An average of 15% of all pregnant women worldwide – nearly 20 million annually – carry the GBS bacterium in their vagina, usually without symptoms.
This can then spread from a pregnant woman to her unborn baby in the womb, or to newborns during labour.
Currently women are given antibiotics during labour as a means of preventing GBS disease in newborns, if the bacterium is detected during pregnancy.
However, the researchers suggest that even in regions with high preventative coverage, there remain significant health risks.
The report calls for researchers, vaccine developers and funders to accelerate development of an effective GBS vaccine that could be administered during routine pregnancy check-ups.
Estimates suggest that if GBS vaccination reached more than 70% of pregnant women, then over 50,000 GBS-related deaths could be averted annually – as well as more than 170,000 pre-term births.
Who is most at risk?
According to the report, the largest burden of GBS is in low and middle-income countries.
The highest rates of maternal GBS are found in sub-Saharan Africa (accounting for around half of the global burden), and Eastern and South-Eastern Asia.
Debbie Forwood, whose daughter Ada was stillborn after they both developed a GBS infection, said: “It is difficult to describe the breadth or depth of the grief when your child dies, or the accompanying guilt, and how it changes you, your family, and your relationships forever.
“Only a GBS vaccine could have saved Ada.
“When a vaccine can be widely rolled out, I will weep and scream with the unfairness that it came too late for her, and for all the other babies who are needlessly suffering and dying every year that it is delayed.
“But I will also weep with joy that in the future, many more will live, and their families will be saved from the living hell that is the death of a child”.
The report was launched at the global conference on GBS, the ISSAD conference being held by the WHO and LSHTM.
Dr Jo Mountfield, vice president of the Royal College of Obstetricians and Gynaecologists, said: “We are all too aware of the devastating consequences GBS can have on babies both here in the UK, but particularly in low-income countries where screening is harder to routinely implement and antibiotic administration during birth not as readily available.
“Around one in every 1,750 newborn babies in the UK and Ireland are diagnosed with early-onset GBS infection each year.
“It’s important pregnant women are informed about GBS as a routine part of their antenatal care and all new parents informed about the key signs of GBS in babies so they can seek vital early treatment, which can save lives”.