Group B streptococcus neonatal invasive infections, France 2007-2012

Area of Science:

• Neonatal infectious diseases
• Bacteriology
• Epidemiology

Background:

• Group B Streptococcus (GBS) causes invasive neonatal infections, presenting as early-onset disease (EOD) or late-onset disease (LOD).
• Intrapartum antibioprophylaxis (IAP) has reduced EOD incidence, but LOD rates remain unchanged.
• LOD constitutes a significant proportion of GBS neonatal infections in industrialized nations.

Purpose of the Study:

• To analyze the clinical and bacteriological characteristics of 438 GBS neonatal invasive infections in France (2007-2012).
• To identify risk factors and prevalent strains associated with EOD and LOD.
• To inform the development of novel prevention strategies for GBS neonatal infections.

Main Methods:

• Retrospective analysis of GBS isolates from neonatal invasive infections reported to the French National Reference Centre for Streptococci.
• Clinical data collected from hospitalization reports and questionnaires.
• Characterization of isolates included capsular type, clonal complex (CC17) assignment, and antibiotic susceptibility.

Main Results:

• LOD accounted for 60.3% of cases, while EOD represented 39.7%.
• LOD was predominantly associated with meningitis (55%), and EOD with bacteremia (61%).
• Capsular polysaccharide (CPS) III and CC17 were significantly associated with LOD, particularly GBS meningitis.

Conclusions:

• LOD is the predominant form of GBS neonatal disease in France, even with IAP.
• The hypervirulent CC17 strain, especially CPS III, is a key target for new prevention strategies.
• Low gestational age and low birthweight are critical risk factors for adverse outcomes in neonatal GBS infections.