[Maternal-fetal vertical transmission of Haemophilus influenzae and Haemophilus parainfluenzae]

Maternal-fetal transmission of Haemophilus influenzae (HI) and Haemophilus parainfluenzae (HPI) as well as characteristics of the infection in the neonate have been poorly described.

From 1982 to 1994 18 HI and 12 HPI from vaginal secretion of 30 women obtained intrapartum or immediately post partum were isolated. The following was observed in the 18 patients in whom HI was isolated: 1 abortion, 2 antepartum death, 1 post partum death, and 14 live neonates from whom 10 were suspect a infection with 5 cases being confirmed with isolation of HI in blood culture. Mortality was 40%. The rate of vertical transmission of HI was 80% (8/10) and neonatal sepsis 50% (5/10) (71.4% of the infants whose mothers did not receive intrapartum antibiotics and 0% in those who did). Twenty-seven point seven percent of the strains of HI were beta-lactamase producers with II and III being the most frequent biotypes observed. Of the 12 patients from whom HPI was isolated the following was reported: 1 antepartum death, and 12 live neonates of whom 10 were suspect a infection, but no case was confirmed because HPI was not isolated from blood culture. The vertical transmission of HPI was 20% (2/10).

The isolation of HI in the vagina of pregnant women should be considered as being potentially very virulent since despite a low prevalence, the rate of vertical transmission and, overall, neonatal sepsis, is high.