Streptococcus agalactiae: Vaginal Carriage, Associated Risk Factors and Antibiotic Susceptibility in Pregnant Women Received at Ouakam Military Hospital Laboratory, Senegal

Introduction: Streptococcus agalactiae or Group B Streptococcus (GBS) is a commensal bacterium of the female reproductive tract that can be pathogenic in newborns. The objectives of this present study were: to determine the rate of vaginal carriage of GBS in pregnant women, the associated risk factors and to evaluate antibiotic resistance.

Methodology: We conducted a prospective, descriptive, analytical study in the medical biology laboratory of Ouakam Military Hospital from July 1, 2022 to June 30, 2023. Identification and antibiotic susceptibility testing were performed using the Vitek 2 COMPACT automated system (bioMérieux). Statistical analysis was performed with RStudio software (version 4.3.2) and differences were considered significant if p<0.05.

Results: We received 327 pregnant women with a mean age of 31.8 ± 5.4 years. Vaginal GBS carriage was 17.74% (58/327), higher in women aged 26-35 years (70.69%), in the third trimester of pregnancy (46.6%), primiparous (46.6%), university-educated (44.8%) and having used contraception at least once (67.2%). It was higher in those with non-fetid leucorrhoea (53.4%), local inflammation (53.4%), local symptoms (67.2%), balanced vaginal flora (75.9%), use of a disposable pad (61.5%), and no previous abortion (58.6%). However, none of these factors was significantly associated with vaginal GBS carriage (p>0.05). There was no resistance to vancomycin, tigecycline, teicoplanin, linezolid and daptomycin, while tetracycline was the least active molecule.

Conclusion: The rate of vaginal carriage of GBS in the pregnant women in our study was relatively high, with no significantly associated risk factors. Non-negligible resistance to penicillin G was noted. However, vancomycin, tigecycline, teicoplanin, linezolid and daptomycin could be therapeutic alternatives.