Molecular Characterization and Antibiogram of Bacteria from High Vaginal Swabs of Pregnant Women Attending Antenatal Clinic at Selected Hospitals in Akwa Ibom State, Nigeria

Introduction: Vaginal bacteria pose a significant public health challenge to female’s reproductive health in Nigeria. This study aimed to characterise the dominant vaginal bacteria and evaluate their antibiotic susceptibility patterns in pregnant women undergoing antenatal care in selected hospitals in Akwa Ibom State. Methodology: Three hundred and sixty (360) high vaginal swab samples were aseptically collected from antenatal attendees and characterised using standard laboratory procedures. The confirmed isolates were subjected to antibiotic susceptibility testing using the Kirby-Bauer diffusion method. The selected bacterial isolates were further characterised using molecular methods. Results: Of 360 HVS samples, 60 yielded significant bacterial growth, giving a 16.7% prevalence of bacteria from HVS. Of the 60 bacterial isolates, 24 (40%) were Enterococcus faecalis, 12 (20.0%) were coagulase negative Staphylococcus, 7 (11.7%) were Enterobacter spp., 5 (8.3%) were Klebsiella spp., 2 (3.3%) were Staphylococcus aureus, Bacillus spp., Acinetobacter spp., and Aerococcus spp., 1 (1.7%) was Streptococcus spp., and 3 (5.0%) were miscellaneous. Gram-positive vaginal bacteria had equal sensitivity rates to erythromycin and azithromycin, 40 (87.0%); levofloxacin 38 and ciprofloxacin, 38 (82.6%); and resistant to amoxicillin-clavulanate, 26 (56.5%). For gram-negative bacteria, imipenem was 100% sensitive, followed by gentamicin 11 (78.6%), ofloxacin and levofloxacin 9 (64.3%), cefotaxime 9 (64.3%), and nitrofurantoin 8 (57.1%). Molecular identification revealed that the selected vaginal isolates included Bacillus amyloliquefaciens, Staphylococcus aureus, Enterococcus faecalis, Enterobacter cloacae, Acinetobacter ursinguii, and Aerococcus urinaeequi. Alcaligenes aquatilis, and Lynsinibacillus fusiformis. The 16S rRNA of these isolates showed a percentage similarity to other species of 99-100% while phylogenetic analysis of the obtained gene sequences revealed a very high level of evolutionary similarities between the isolates obtained in this study and those deposited in the NCBI database. Conclusion: This study confirmed the vaginal microbiota of pregnant women and provides novel insights into bacterial diversity and antibiograms for the therapeutic management of vaginal infections.