SA researchers make headway against silent baby killer

20 November 2017 - 12:48 By Tanya Steenkamp
Worldwide, the bacteria Group B Streptococcus kills 90‚000 newborns each year.
Worldwide, the bacteria Group B Streptococcus kills 90‚000 newborns each year.
Image: 123RF/vitalinka

Lesego Letlhake died when she was just two weeks old. She had contracted a fatal bacteria from her mother before or during birth‚ which developed into meningitis.

Devastated mom Palisa had no idea she had Group B Streptococcus (GBS)‚ an asymptomatic bacteria found in about 20% of pregnant women globally.

While it lives harmlessly in the digestive tract or lower vaginal tracts of women‚ it is a silent killer of babies‚ causing serious infections as well cerebral palsy and permanent loss of hearing or sight.

Worldwide‚ the bacteria kills 90‚000 newborns each year. South Africa has one of the highest incidences of GBS‚ with more than 1‚700 infants succumbing to it each year‚ 1‚250 of whom are stillborn.

But hope is on the horizon. South African researchers are among a global group of scientists who are developing a vaccine that has been 80% effective during initial trials.

The Wits/Medical Research Council respiratory and meningeal pathogens research unit has completed the first study of an investigational GBS vaccine in pregnant women‚ which has been published in the Lancet Infectious Diseases journal. The vaccine was tested on 60 non-pregnant and 320 pregnant South African women at Chris Hani Baragwanath Academic Hospital.

"This was the first clinical trial of this vaccine undertaken in pregnant women‚ which includes three 'strains' of GBS‚" said the unit's head‚ Prof Shabir Madhi.

"The vaccine was shown to be safe in pregnant women‚ although it was not as immunogenic as we hoped for in HIV-infected women. The vaccine is now being reformulated to expand the number of strains which [will] provide a higher effectiveness."

The study‚ which is being coordinated by The London School of Hygiene and Tropical Medicine‚ is the first comprehensive study of its kind and involves about 100 countries. A second study has also be conducted in Malawi and the third phase will involve thousands of participants from across the globe.

South Africa has recorded a higher incidence of invasive GBS disease than any other country over the past 20 years

Madhi said South Africa had recorded a higher incidence of invasive GBS disease (at three per 1‚000 live births) than any other country over the past 20 years. This was compared to the global average of 0.54 per 1‚000 and an average of one per 1‚000 live births in Africa.

The unit's deputy director‚ Dr Clare Cutland‚ said it was unclear when phase three trials would start.

"The sooner the better‚ but there are a lot of factors that impact that. It would be a good five-plus years before results of a phase three trial would be ready and probably close on 10 years until a vaccine that's found to be safe and effective would be close to coming on the market."

She said the aim was to vaccinate all pregnant women‚ as testing for GBS was "resource intensive".

The vaccine would enable the body to create the antibodies to protect the unborn baby.

"That has been used very widely for Tetanus and very successfully‚" she said.

The rollout of the vaccine would mean thousands of women would not have to experience what Palisa did.

Two years after the tragedy‚ Palisa is pregnant again. She and her husband said their prayers had been answered‚ with their daughter due to be born within the next few weeks.

This time‚ doctors will be ready to administer antibiotics to Palisa as soon as she goes into labour. However‚ this treatment is not a guarantee. While the antibiotics will protect the infant for its first week of life‚ there is still a chance the baby could contract a GBS-related disease between the ages of one week and four months old.

While they are still debating names‚ Palisa said she's set on calling her daughter Reneilwe‚ meaning "we are given". - TimesLIVE