Bacterial Colonisation and Antimicrobial Resistance in Mother-Neonate Dyads

Abstract

Maternal bacterial carriage is influential in neonatal colonisation and is a factor in the transfer of bacterial infections from mother to child. However, there is scant evidence on this from resource-constrained circumstances. This cross-sectional research determined the frequency, antibiotic susceptibility profiles and transmission of bacterial infections among 50 mother-infant dyads at Niger Delta University Teaching Hospital and Federal Medical Centre, Yenagoa, Nigeria. Maternal nasal and hand swabs and neonatal umbilical cord swabs were collected from October 2024 to March 2025. Bacteria were isolated, identified and their sensitivity to antimicrobial agents was determined using conventional microbiological procedures. A total of 269 bacterial isolates were recovered from 150 specimens. 23 pairs (46%) shared at least one bacterial species, with Staphylococcus aureus being most frequently matched (48.70%), followed by Staphylococcus epidermidis (22.68%), Pseudomonas aeruginosa (10.04%), and Escherichia coli (6.69%). All the organisms isolated in this study were resistant to amoxicillin, augmentin, cefuroxime, methicillin, and oxacillin. The incidence of resistance to cloxacillin (99.26%), ceftriaxone (99.63%), erythromycin and vancomycin (92.94%), were very high, but all the organisms isolated were sensitive to imipenem. Chi-square analysis revealed associations between neonatal colonisation, shared isolates and shared organisms, but not with delivery mode, gender, or medical conditions. These findings suggest that maternal bacterial carriage can be an important contributor to early neonatal colonisation, and the high prevalence of resistance to first-line antibiotics and the retention of carbapenem sensitivity shows a need for maternal screening, infection control, and the implementation of antimicrobial stewardship programmes in Nigerian healthcare settings.