Burden and risk factors of invasive group B Streptococcus disease among neonates in a Chinese maternity hospital

BACKGROUND: There is a lack of data regarding the prevalence of invasive group B streptococcus (GBS) infection among neonates in China. This study aimed to investigate the incidence and mortality of invasive GBS infection and to identify the risk factors in our hospital. METHODS: Seventy-four cases admitted between January 2011 and December 2016 was included in this study. A retrospective matched case-control study was conducted in a tertiary maternity and paediatric hospital. Risk factors for the acquisition of invasive GBS infection and mortality were analysed by univariable and multivariable analysis. RESULTS: We collected and analysed data from 74 infants aged < 3 months with invasive GBS infection. Among 67,985 live births, we calculated an incidence of 1.09 per 1000 live births (95%CI:0.81–1.37%); the incidence of Early-onset GBS disease (EOD, n = 65) and Late-onset GBS disease (LOD, n = 9) were 0.96‰(95%CI:0.73–1.19%) and 0.13‰(95%CI:0.04–0.22%), respectively. Overall, pneumonia accounted 63.1% (41/65) of EOD, and sepsis accounted 88.9% (8/9) cases of LOD, respectively. The overall case fatality rate was 8.11% (6/74), including 7.69% (5/65) among cases of EOD and 11.1% (1/9) among cases of LOD. No predictor of mortality was found. Membrane stripping (P = 0.005, aOR: 3.68, 95% CI: 1.48–9.13) and non-resident mother (P < 0.001, aOR: 5.88, 95% CI: 2.36–14.61) were independent risk factors for EOD; no increased risk was found for LOD. CONCLUSIONS: This study demonstrates remarkable country-specific variation in comparison with other countries. Our findings can improve awareness of neonatal GBS infection and lay a cornerstone to ensure accurate representation of the burden.