Increased Risk for Invasive Group A Streptococcus Disease for Household Contacts of Scarlet Fever Cases, England, 2011-2016

Emerg Infect Dis. 2019 Mar;25(3):529-537. doi: 10.3201/eid2503.181518. Epub 2019 Mar 17.


The incidence of scarlet fever in England and Wales is at its highest in 50 years. We estimated secondary household risk for invasive group A Streptococcus (iGAS) disease within 60 days after onset of scarlet fever. Reports of scarlet fever in England during 2011-2016 were matched by residential address to persons with laboratory-confirmed iGAS infections. We identified 11 iGAS cases in ≈189,684 household contacts and a 60-day incidence rate of 35.3 cases/100,000 person-years, which was 12.2-fold higher than the background rate (2.89). Infants and contacts >75 years of age were at highest risk. Three cases were fatal; sepsis and cellulitis were the most common manifestations. Typing for 6 iGAS cases identified emm 1.0 (n = 4), emm 4.0 (n = 1), and emm 12.0 (n = 1). Although absolute risk in household contacts was low, clinicians assessing household contacts should be aware of the risk to expedite diagnosis and initiate life-saving treatment.

Keywords: England; Streptococcus pyogenes; bacteria; household contacts; iGAS disease; incidence; invasive group A Streptococcus disease; respiratory infections; risk; scarlet fever; streptococcal infections; streptococci.

Publication types

  • Historical Article

MeSH terms

  • Child
  • Child, Preschool
  • England / epidemiology
  • Family Characteristics
  • Female
  • History, 21st Century
  • Humans
  • Incidence
  • Infant
  • Male
  • Retrospective Studies
  • Risk Assessment
  • Risk Factors
  • Scarlet Fever / epidemiology*
  • Scarlet Fever / history
  • Scarlet Fever / microbiology
  • Scarlet Fever / transmission*
  • Streptococcal Infections / epidemiology*
  • Streptococcal Infections / history
  • Streptococcal Infections / microbiology
  • Streptococcal Infections / transmission*
  • Streptococcus pyogenes*