A population-based cohort study in Sweden suggests prenatal antibiotic exposure is associated with increased risk of group B Streptococcus (GBS) disease in newborns, researchers reported last week in the Journal of Infection.

The study, led by researchers at Sweden’s Karolinska Institutet, used four Swedish national registries to examine prenatal antibiotic exposure during all singleton live births in Sweden from 2006 to 2016. Although intrapartum antibiotic prophylaxis (prevention), guided by risk-based strategies, was implemented by Sweden in 2008 to prevent GBS transmission from mother to newborn during the intrapartum period (all stages of labor and delivery) and reduce early-onset GBS disease, GBS still accounts for 40% of severe early-onset infections in Swedish newborns. Some research has suggested a moderately increased risk of infection in children who had prenatal antibiotic exposure.

“Given the widespread use of antibiotics during pregnancy (~25% of pregnancies globally), rising GBS resistance, and the lack of licensed maternal GBS vaccine, this potential association warrants further studies,” the study authors wrote.

29% increased risk of GBS disease in antibiotic-exposed newborns

Among 1,095,644 liveborn singletons, prenatal antibiotic exposure was recorded in 24.5%, of which 4.9% were exposed in more than one trimester. During the study period, the overall incidence of GBS disease was 0.71 per 1,000 live births.

Compared with unexposed newborns, GBS incidence within four weeks postpartum was higher among exposed newborns (0.86 vs 0.66 per 1,000 live births), for an increased risk of 29% (adjusted odds ratio [aOR], 1.29). Among pregnancies without any GBS risk factors, prenatal antibiotic exposure was associated with a 34% higher risk of GBS disease (aOR, 1.34), while no association was observed among pregnancies with at least one risk factor (aOR, 0.91). The strongest association was observed with early third-trimester antibiotic exposure (aOR, 1.67).

Although the authors say it’s too early to draw causal conclusions and further confirmation of the association is needed, they suggest the findings hint at a possible mechanism involving antibiotic-induced disruption of the maternal microbiota, particularly a decline in Lactobacillus species, which dominate the vaginal microbiome and help prevent GBS colonization.

“Studies with detailed intrapartum antibiotic data and dose-response analyses are needed to provide a more complete picture of this important topic,” they wrote.

The Louisiana Department of Wildlife and Fisheries (LDWF) has announced the first case of chronic wasting disease (CWD) in a wild deer in Concordia Parish.

Concordia Parish is in east-central Louisiana, on the Mississippi River. The infected buck was taken by a hunter in the Richard K. Yancey Wildlife Management Area, LDWF said this week. The department said that it is implementing its CWD response plan. 

“We will continue to count on our hunters, property owners, deer processors and taxidermists for their assistance in monitoring CWD as their continued partnership with our department will help manage the expanse of CWD in the state keeping our deer population healthy,’’ LDWF Secretary Tyler Bosworth, JD, said in the news release.

Free CWD testing of hunter-harvested deer

Since CWD was first found in Louisiana in 2022, the state has tallied 49 positive cases. CWD is a neurodegenerative disease of cervids such as deer, moose, and elk. It spreads from animal to animal and via environmental contamination through infectious misfolded proteins called prions. It causes symptoms such as emaciation, excessive salivation and thirst, lack of coordination, loss of fear of humans, and eventually, death.

It is recommended that people hunting in areas known to harbor CWD-infected deer have their deer tested for the disease prior to consumption.

"Although CWD has not been shown to be contagious to humans, the Centers for Disease Control and the World Health Organization recommend against the human consumption of deer known to be infected with CWD,” LDWF said. 

“Also, it is recommended that people hunting in areas known to harbor CWD-infected deer have their deer tested for the disease prior to consumption,” it added. “LDWF provides CWD testing for hunter-harvested deer free of charge.”

• Today the Coalition for Epidemic Preparedness Innovations (CEPI) and the European Union’s Horizon Europe program announced $26.7 million in funding for new vaccine development of filoviruses, including Ebola virus, Sudan virus, Bundibugyo virus, and Marburg virus. A team at the University of Oxford will lead the research. There are two licensed vaccines for Ebola virus, but no vaccines are licensed for Sudan virus or Marburg virus. CEPI CEO Richard Hatchett, MD, said in a press release, “The first-ever outbreak of Marburg in Ethiopia is a stark reminder that filoviruses are among the world’s most menacing pathogens, capable of triggering devastating outbreaks and epidemics. A broadly protective filovirus vaccine could be transformative, protecting those most vulnerable to these viral threats and strengthening global health security against both known and emerging members of the filovirus family.”
• Virometix AG, a biotech company, today announced positive topline data from a phase 1 trial of V-212, a serotype-independent pneumococcal vaccine candidate, in development for the prevention of pneumococcal disease cause by Streptococcus pneumoniae infections. The vaccine candidate proved to be safe among 60 healthy volunteers aged 18 to 45 years, and the data showed evidence of a robust increase in immunoglobulin G antibodies.
• The nonprofit scientific research organization IAVI said earlier this week that the first doses of experimental HIV vaccine antigens had been administered as part of the IAVI G004 clinical trial in December at the Perinatal HIV Research Unit in Soweto, South Africa. Three antigens will be delivered via Modern’s mRNA platform, and the trial will assess safety, immune responses, and dose levels. “With this year’s global funding cuts to HIV prevention, care, and treatment, bringing new prevention tools forward is more important than ever. We believe we are on the most promising path ever pursued for the development of an effective vaccine against HIV,” said IAVI President and CEO Mark Feinberg, MD, PhD, in a press release.