Magnitude and Type of Maternal Bacterial Colonisation at Delivery and Risk of Early-onset Neonatal Sepsis of their babies admitted to Neonatal Intensive Care Unit at University Teaching Hospital, Lusaka, Zambia

Abstract

The incidence of early neonatal deaths and infections varies worldwide depending on the quality of antenatal care, intrapartum services and neonatal intensive care unit services. It is estimated that ninety eight percent of newborn deaths due to infections occur in developing countries mostly in Africa and Asia while two percent occur in developed countries. According to the Perinatal Audit Reports for the University Teaching Hospital, Neonatal Intensive Care Unit (UTH, NICU) in 2015, sixty percent of the admissions resulted in neonatal deaths within seven days of life. There were several different causes attributed to these deaths, but fifty percent were due to neonatal infections. Of these almost two-thirds (62.4%) were due to early onset sepsis. This study aimed at exploring the maternal bacterial colonisation of the vagina and perineum of the women in labour at UTH and whether it resulted in early infections in their newborn babies admitted to NICU. This was a prospective cross-sectional study of women that delivered a singleton baby by vaginal delivery whose newborns were admitted to NICU for any reason. After consent, a structured interviewer administered questionnaire was used to collect the demographic, reproductive, medical, perinatal and social characteristics of the women. Vaginal and rectal swabs (to represent perineum) were taken from the eligible mothers in the immediate postpartum period and sent to the UTH laboratory for microscopy, culture and sensitivity. Similarly, blood cultures from the eligible newborns, as was standard of care, were also collected before administration of any antibiotics at admission to NICU. The descriptive data of the maternal and newborn characteristics and their culture results were presented in summary form. Ninety-four mother-newborn dyads were enrolled. Of these, 87 (92.6%) of the vaginal swabs had normal flora on culture. A further 7 (7.4%) had Escherichia coli, Morganella morganii, Staphylococcus species and Staphylococcus epidermidis isolated. Also, 92 (97.9%) of the rectal swabs had normal flora isolations and 2 (2.1%) with Salmonella species isolated. There were no beta haemolytic Streptococcus in either swabs. The newborns blood culture results showed 93 (98.9%) with no growth and no isolations and 1(1.1%) with Staphylococcus epidermidis isolated attributed to possible contamination. This study population showed women in labour could not be the likely source of the high levels of infections in the newborns as previously suspected. The conclusion from this study was that maternal colonisation of the vagina and rectum in the study population showed no Group B streptococcus but a predominance of normal flora. There were no isolations in the blood cultures taken at admission from the newborns in NICU and hence it was not possible to link maternal colonisation with early newborn infections of babies admitted to NICU in this series. Studies with larger numbers are needed to better understand the source of early newborn infections. Continued surveillance and infection prevention measure are recommended.