Fighting Group B Streptococcus in the hardest hit places

One of the earliest and most dangerous health threats young infants face is one many parents have never even heard of: Group B Streptococcus (GBS), which causes a bacterial infection that can take hold at or within a few hours of birth. The leading cause of sepsis and meningitis in young infants worldwide, GBS reportedly causes more infant deaths than HIV, and more than tetanus, pertussis, and respiratory syncytial virus combined. It can even cause problems during pregnancy: GBS has been linked to preterm birth, miscarriage, and stillbirth.

Nearly 20 percent of women worldwide carry the GBS bacterium, which can live in the gastrointestinal tract and the vagina and be passed from mother to baby in the womb or during birth. This can be managed, to some extent, by screening pregnant women and administering prophylactic antibiotics during labor if they’re found to be GBS carriers. This can contribute, however, to antibiotic overuse and resistance. Not to mention, it is expensive and logistically challenging, especially for the low-income countries that face the highest disease burden.

Across Africa, studies estimate that 8 million infants are exposed to GBS annually, leading to 169,000 cases of infant disease; 42,000 stillbirths; 54,000 infant deaths; and 6,400 infants who suffer moderate to severe long term disabilities. That African nations alone account for 54 percent of all estimated GBS cases and 65 percent of GBS-linked stillbirths and infant deaths represents the inherent inequity in our current treatment and prevention methods. [1]

We’re going to change that. And we’re going to do it with a vaccine. PATH is working with the Biovac Institute in South Africa—a country that suffers one of the highest GBS disease burdens in the world—to develop a vaccine against GBS that can be delivered to pregnant women, who will then pass along protective antibodies to their babies.

But don’t just take our word for it. Dr. Ziyaad Dangor, a pediatrician at the University of Witwatersrand in Soweto, South Africa and a longtime GBS researcher shared his thoughts on why a GBS vaccine is desperately needed, and why it should be developed in, and for, the places hardest hit.

Dr. Dangor is not affiliated with PATH or Biovac, or the vaccine development project.

Pediatrician and GBS researcher Dr. Ziyaad Dangor.

How long have you been studying and treating GBS?

I joined the research team in 2011 and was part of it for several years; I enrolled the study participants myself and had a lot of first-hand experience with the disease. And I saw that a large proportion of babies who contracted GBS were extremely ill.

In 2014, I returned to clinical work as a pediatrician but I try to continue my work on GBS whenever able. And of course I see cases here in the hospital.

What’s the emotional toll of working with such a vulnerable population?

Working in a hospital, we’re faced with heartbreaking situations and difficult decisions. We see a lot of death and disability. That’s just the reality. The thing that saddens me the most is how quickly the disease sets in. How quickly you reach a point where there’s nothing you can do. How does a baby die that quickly? GBS can cause such severe injury and such significant mortality. All I’ve done for five years is study this one little germ, and I still can’t get my head around that.

Do people prioritize GBS prevention and treatment? Is it something they are asking for?

In most cases, GBS is something people are completely unaware of. The first time they find out about it is when their child is diagnosed with it. That’s true for some doctors, too—the first time they truly learn about it is the first time they encounter it. And it’s a shame because people need to understand that this bug is causing a lot more damage than we think.

With so many competing health priorities, especially in low- and middle-income countries, why should people care about addressing GBS?

To really see the impact, I’ll break it down to numbers.

Every month we have six babies that get hospitalized with this disease. One dies before you can intervene. One survives, but will likely become a cerebral palsy patient. In a year, you lose twelve babies. And that’s just at this hospital.

And it’s terrible, absolutely terrible, to know that this can all be prevented.

What type of burden does that place on South African families?

I think the context that we come from, a setting where a lot of the population is already struggling with so much, makes it a lot worse. Here in Soweto, even though we are very close to Johannesburg town, the economic status is very different. Between 20 and 40 percent of Soweto’s residents live on less than $2 USD a day. We have mothers coming in to the hospital who don’t have enough money to get back home. So when death and disability hits these families, it’s very hard for them because they are already coming from such a difficult background. They have no time to process the suffering because they may have to deal with something else—there may be another child to care for, they need to put food on the table. The struggle just goes on and on for them.

Are there any prevention measures in place for pregnant women?

In South Africa, we mostly use a risk-based screening approach. We do not generally screen all pregnant women for carriage. But this strategy has been failing for years. It’s not that it’s a bad strategy, but you have to take into context that in lower income settings, it can be a lot harder to identify everyone who is at risk because of resource constraints at health facilities.

Maternal immunization—the practice of vaccinating a pregnant mother in order to protect her baby from disease—could be a promising strategy to shield young infants from a potentially deadly infection. Photo: PATH/Evelyn Hockstein

What would a GBS vaccine mean for South Africa?

Quite simply, it is the best thing that would work for our setting. Screening for disease carriage does not make sense here from a logistical standpoint. We have on average 60 babies born in this hospital every day—that’s 60 women who require antenatal care. If they were screened, someone would have to collect and process those specimens, find a healthcare worker to report the results, then track down those women to institute antibiotic prophylaxis.

But vaccination is a simpler solution. Give a pregnant woman the GBS vaccine and even if you don’t see her again until the day she presents in labor at the hospital, you know she and her baby are protected.

And to develop and deliver such a vaccine locally—that would help raise awareness of this disease. It would help neonatologists and obstetricians to be more connected on their management and treatment; it would help the public to be more motivated in taking action against GBS; and it would help ensure South Africa—Africa, really—has access to such an intervention.

A vaccine is really the key to turning this around. Simple measures often have the largest impacts.

[1] Seale A, Bianchi-Jassir F, Russell N, et al. GBS in Pregnant Women, Stillbirths, and Children. CID. 2017:65 (Suppl2).

This blog was originally posted on the PATH site.

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