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Updated: May 14, 2026

A Murine Model of Group B Streptococcus Vaginal Colonization
Published on: November 16, 2016
Recurrent late-onset group B Streptococcus sepsis in a preterm infant acquired by expressed breastmilk transmission:
Gaurav Jawa1, Zafar Hussain, Orlando da Silva
1Children’s Hospital London Health Sciences Centre, Schulich School of Medicine and Dentistry, University of Western Ontario, London,Ontario, Canada.
Group B Streptococcus is a known cause of neonatal sepsis, being more common in the early period by maternal genital tract transmission and less so in the late neonatal period, ascribed to intestinal colonization or horizontal transmission. Although breastmilk transmission of Group B Streptococcus has rarely been reported in the past, most cases are of patients nursed on the mother's breast and less commonly in expressed breastmilk-fed infants. This case describes a preterm infant (born at a gestational age of 24 weeks 6 days) in the neonatal intensive care unit who acquired recurrent late-onset sepsis with Group B Streptococcus with the mother's expressed breastmilk culture growing the same organism that was later matched to the infant's isolate. The mother had presented with features of mastitis only during the second episode of sepsis and was then treated with oral antibiotics. The infant was fed on formula feeds after the second incidence and remained healthy, being discharged on a regular follow-up plan at 39 weeks corrected gestational age.
Group B Streptococcus is a known cause of neonatal sepsis, being more common in the early period by maternal genital tract transmission and less so in the late neonatal period, ascribed to intestinal colonization or horizontal transmission. Although breastmilk transmission of Group B Streptococcus has rarely been reported in the past, most cases are of patients nursed on the mother's breast and less commonly in expressed breastmilk-fed infants. This case describes a preterm infant (born at a gestational age of 24 weeks 6 days) in the neonatal intensive care unit who acquired recurrent late-onset sepsis with Group B Streptococcus with the mother's expressed breastmilk culture growing the same organism that was later matched to the infant's isolate. The mother had presented with features of mastitis only during the second episode of sepsis and was then treated with oral antibiotics. The infant was fed on formula feeds after the second incidence and remained healthy, being discharged on a regular follow-up plan at 39 weeks corrected gestational age.
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