Control measures for invasive group A streptococci (iGAS) outbreaks in care homes

J Infect. 2012 Feb;64(2):156-61. doi: 10.1016/j.jinf.2011.11.017. Epub 2011 Nov 23.

Abstract

Objectives: The incidence of invasive group A streptococcal infections (iGAS) is increasing in Europe, with a particularly high morbidity and mortality in the elderly. Control of outbreaks in care homes is therefore important; but is unclear how best to manage these incidents. We attempted to identify which control measures are most likely to be effective.

Methods: We undertook literature searches using PubMed and Google Scholar and contacted colleagues in Health Protection Units in England for unpublished outbreaks.

Results: We identified 31 outbreaks; of which 20 had sufficient detail for further analysis. Overall carriage rates of GAS in care home residents identified in outbreak investigations were 4.7%, and in staff 3.2%. In 8 outbreaks mass antibiotic prophylaxis was offered, in 9 selective prophylaxis only and in 3 none at all. Surveillance swabbing had limited influence on decisions regarding prophylaxis. A few papers mentioned the role of environmental contamination and the risk from an affected roommate.

Conclusions: Pooling of results from these outbreaks failed to suggest any clear advantage to either a selective or mass antibiotic prophylaxis strategy in controlling spread. Systematic investigation and data collection from future outbreaks could be of benefit in informing future policy.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Antibiotic Prophylaxis
  • Cross Infection / epidemiology
  • Disease Outbreaks / prevention & control*
  • Disease Outbreaks / statistics & numerical data*
  • England / epidemiology
  • Europe / epidemiology
  • Humans
  • Nursing Homes / statistics & numerical data*
  • Streptococcal Infections / epidemiology*
  • Streptococcal Infections / mortality
  • Streptococcal Infections / prevention & control*
  • Streptococcus pyogenes* / pathogenicity