Magnitude of maternal vaginal colonization of Group B streptococcus and neonatal transmission in pregnant women during labor and delivery at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia


  • Yitbarek Fantahun
  • Shemse Sebre
  • Aminu Seman
  • Solomon Kumbi


Background and aim: Streptococcus agalactiae or Group B Streptococci (GBS) frequently colonizes the human genital and gastrointestinal tract and a risk factor for subsequent infection in pregnant women and newborns. The study was conducted to determine the prevalence of maternal vaginal colonization of GBS during delivery, transmission rate to the newborns, to identify the possible risk factors and determine the antimicrobial susceptibility pattern of GBS isolates. 

Subjects and Methods: A cross-sectional study design was used to enroll 250 pregnant women coming for delivery at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia. Both maternal vaginal and neonatal oropharyngeal swabs were collected and inoculated onto CHROMagarTM StrepB and 5% sheep blood agar plates. Isolates were identified based on the mauve color on GBS CHROMagar, colony morphology, gram reaction and hemolysis on 5% sheep blood agar. Antimicrobial susceptibility testing was performed by using Kirby–Bauer disk diffusion method according to the Clinical Laboratory Standard Institute (CLSI) guidelines.

Results: The overall prevalence of GBS colonization among the participants was 23.6% with a transmission rate to the newborns of 47.4%. GBS colonization was significantly associated with occupation and parity (p< 0.05) GBS isolates had significantly high resistance level to cefepime (59.4%) and penicillin (57.7%). Highest susceptibility to vancomycin (93.3%), clindamycin (86.4%) and chloramphenicol (79.6%) were observed.

Conclusions: There was high rate of maternal colonization and maternal to child transmission of GBS with high resistance to commonly used antibiotics.

Keywords: Antibiotics susceptibility, Group B streptococcus, Intra-partum antibiotic


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How to Cite

Fantahun, Y. ., Sebre, S. ., Seman, A. ., & Kumbi, S. . (2020). Magnitude of maternal vaginal colonization of Group B streptococcus and neonatal transmission in pregnant women during labor and delivery at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia. Ethiopian Medical Journal, 58. Retrieved from