331 Choosing Strategy for Prevention of Neonatal Group B Streptococcal (GBS) Infection - Has Maternal Origin Country to be Consider?

Abstract

Background: During the last two decades our maternal GBS carrier and neonatal sepsis rates has varied, 3.5%–11% and 0.2–0.9/1000 LB respectively. Thus, Israeli current policy is Risk Factor Approach with no routine GBS screening.Objective: 1. To update colonization & attack rate. 2. To determine whether our Risk factor Approach is still applicable.Design/Methods: In Jan.-June 2002 we randomly sampled women admitted for delivery. Vaginal & rectal cultures were obtained before 1st pelvic examination. GBS was isolated using a selective broth medium and identified by latex agglutination and antigen B assay. Neonatal sepsis/meningitis rate was defined as positive blood/CSF cultures in 2002. Chi2 and multivariate analysis were performed.Results: Of the 637 sampled women 94 were GBS positive (14.7%). Fifty (7.8%) of the mothers were from N. America origin and there colonization rate was 26% (13:50) as opposed to mothers of other origins which was 13.8% (81:587) p= 0.02. In multivariate analysis, including variables of maternal age, parity, blood type, duration of rupture of membranes, infant gender and birth weight, N. America Origin was found to be the single risk for GBS carrier (p= 0.0273). Neonatal sepsis (8:9995) rate was 0.8/1000 LB for the entire population. The percentage of the N. America Origin mothers in the sampled population was 7.8% (50/637) their component in the GBS infected group was 37.5% (3:8) p=0.016. No difference was noted in GBS serotypes between origin groups.Conclusions: We identified N America origin women as an increased risk factor for GBS colonization in the Israeli society. The high N American origin neonatal GBS sepsis rate was correlated with the higher colonization rate in these mothers. Given our high carrier & attack rate in N. America origin women & babies we now recommend routine prenatal screening in that ethnic subgroup.