[Epidemiology and prevention of perinatal group B streptococcal infections].

Neonatal group B streptococcal infection is frequent and may be responsible for lethal neonatal septicaemia. Its preventive treatment is still hotly debated. Digestive and genital tracts colonization is frequent in mother (15-20% of the cases) but it is unstable. About one out of two infants born of a colonized woman becomes colonized or infected. Neonates can also be colonized during their stay in maternity hospitals. Colonization is much more frequent than infection which strikes 0.2 to 0.6 per cent of neonates (at a very early period in two-thirds of the cases), but it jeopardizes their prognosis for life and later their functional prognosis. Prematurity and chorioamnionitis are the two main infection facilitating factors. Some of the various measures proposed to prevent infection in neonates, such as antibiotic therapy of colonized mothers during pregnancy and of symptomatic colonized neonates, do not seem to be effective, but others are interesting, including administration of antibiotics to mothers during delivery in high-risk situations, combined with early detection and immediate bactericidal treatment of neonatal infections.