Hospital clusters of invasive Group B Streptococcal disease: A systematic review

J Infect. 2019 Dec;79(6):521-527. doi: 10.1016/j.jinf.2019.11.008. Epub 2019 Nov 13.


Objectives: To characterize outbreaks of invasive Group B Streptococcal (iGBS) disease in hospitals.

Methods: Systematic review using electronic databases to identify studies describing iGBS outbreaks/clusters or cross-infection/acquisition in healthcare settings where 'cluster' was defined as ≥2 linked cases. PROSPERO CRD42018096297.

Results: Twenty-five references were included describing 30 hospital clusters (26 neonatal, 4 adult) in 11 countries from 1966 to 2019. Cross-infection between unrelated neonates was reported in 19 clusters involving an early-onset (<7 days of life; n = 3), late-onset (7-90 days; n = 13) index case or colonized infant (n = 3) followed by one or more late-onset cases (median serial interval 9 days (IQR 3-17, range 0-50 days, n = 45)); linkage was determined by phage typing in 3 clusters, PFGE/MLST/PCR in 8, WGS in 4, non-molecular methods in 4. Postulated routes of transmission in neonatal clusters were via clinical personnel and equipment, particularly during periods of crowding and high patient-to-nurse ratio. Of 4 adult clusters, one was attributed to droplet spread between respiratory cases, one to handling of haemodialysis catheters and two unspecified.

Conclusions: Long intervals between cases were identified in most of the clusters, a characteristic which potentially hinders detection of GBS hospital outbreaks without enhanced surveillance supported by genomics.

Keywords: Adult; Cluster; Group B streptococcal disease; Healthcare-associated infection; Neonatal; Outbreak; Streptococcus agalactiae; Systematic review.

Publication types

  • Research Support, Non-U.S. Gov't
  • Systematic Review

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Bacteriophage Typing
  • Cluster Analysis
  • Cross Infection / epidemiology*
  • Cross Infection / microbiology
  • Disease Outbreaks*
  • Epidemiological Monitoring
  • Female
  • Hospitals
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Middle Aged
  • Molecular Typing
  • Neonatal Sepsis / epidemiology*
  • Neonatal Sepsis / microbiology
  • Streptococcal Infections / epidemiology*
  • Streptococcal Infections / microbiology
  • Streptococcus agalactiae / isolation & purification*