Molecular characterization of high-risk infection vaginal bacteria isolated from pregnant women in CHU-MEL of Cotonou (Benin)

The aim of this study is to determine the distribution of the genotypic pathogenicity traits of vaginal high-risk infectious bacteria (HRIB) collected in the CHU-MEL of Cotonou (Benin). To achieve this, a recto-vaginal swab of 42 pregnant women in the third trimester of pregnancy was collected. Species identification was carried out by specific biochemical tests. Antimicrobial susceptibility was tested according to the microbiology standard recommendation. Macrolide resistance genes in Gram-positive bacteria and virulence genes in Escherichia coli were investigated by polymerase chain reaction (PCR). E. coli is the most isolated species (14.7%) followed by Klebsiella pneumoniae (11.8%). Mono-microbial carriage was 55.9%. Gram-negative antibiotic susceptibility shows strong resistance to beta lactam. While Gram-positive bacteria showed strong resistance to beta-lactamine, tetracycline and macrolides with cMLS B (70.4%), iMLS B (3.7%) and M (25.9%) phenotypes. ErmB and ermTR were not detected in Gram-positive bacteria but mef(A/E) was detected at a high. Virulence genes in E. coli were detected and fimA was the most common (52.2%) followed by sfa/foc (30.4%) and cnf1 (13.0%). NeuC and ibeA have not been detected. The hvgA virulence gene was detected in S. agalactiae at a rate of 61.54%. These results demonstrate the importance of introducing antenatal screening for HRIB to improve obstetric and neonatal management in Benin.