Invasive Group A Streptococcus
Current Situation:
Hamilton Public Health Services (PHS) is notifying health care providers of invasive Group A Streptococcus (iGAS) case trends. Locally, iGAS has remained stable in Hamilton across all age groups. In 2023, currently there have been 25 confirmed cases, which is consistent with other years. However, in the last 6 months, we have had 3 cases in the 0-9 age group with severe outcomes. While the number of pediatric cases hasn’t increased in Hamilton, given the increase in severe outcomes, providers are asked to be vigilant and ensure prompt diagnosis and treatment of pediatric GAS.
Background:
Group A streptococcus is caused by Streptococcus pyogenes and typically causes mild illness such as strep throat and impetigo. Invasive GAS may cause severe illness such as sepsis, toxic shock, necrotizing fasciitis and in rare cases can lead to death.
GAS is spread by direct contact with secretions from the nose, throat or wound of an infected person. Co-infection with respiratory viruses and varicella are risk factors for developing pediatric iGAS. People with iGAS are infectious for about 7 days before symptom onset until 24 hours after appropriate antimicrobial treatment has been initiated. Viral infections, such as influenza and varicella, have been identified as risk factors for iGAS infection in children, adolescents, and adults and can be reduced by vaccination.
Action Required:
Hamilton PHS is requesting health care providers to:
- Consider iGAS as part of your differential diagnosis. Initiating treatment as soon as possible is key to preventing severe disease.
- Ensure your patients are up to date with all their routine vaccinations (including varicella).
- Encourage annual influenza vaccination for all patients 6 months of age and older. Refer to NACI guidelines for age-specific recommendations for influenza vaccine types.
Reporting Requirements
Invasive Group A Streptococcus (iGAS) disease is reportable to the Medical Officer of Health under the Health Protection and Promotion Act, R.S.O. 1990, c. H.7.
Reporting to Hamilton Public Health Services:
To report suspect and confirmed iGAS cases, call PHS Monday to Friday, 8:30 am to 4:30 pm at 905-546-2063 or fax 905-546-4078. After-hours, on weekends and holidays please ask to speak with the on-call Public Health Nurse.
For more information about iGAS, please visit our website: www.hamilton.ca/InfectiousDisease
Resources
Canadian Immunization Guide. Available at: https://www.canada.ca/en/public-health/services/canadian-immunization-guide.html
Canadian Paediatric Society. (2019). Available at: https://cps.ca/en/documents/position/Invasive-group-A-streptococcal-disease