GAS – Group A Streptococcus – Serotyping

Specimen Collection and Handling

Specimen Requirements

Test Requested Required Requisition(s) Specimen Type Minimum Volume Collection Kit

Group A Streptococcus – Serotyping

Pure isolate on a blood agar plate; or swab of pure isolate in Amies charcoal media3

Submission and Collection Notes


Enter outbreak number on the requisition if this is related to an outbreak.


Indicate the following on the requisition:

  • test requested
  • culture information 
  • clinical/epidemiology

Primary cultures are not acceptable; and must be processed by the originating lab. The submitter will be contacted by telephone prior to rejection of the primary sample followed by a written report to indicate that the test has been rejected.

Storage and Transport

Label the specimen container with the patient’s full name, date of collection and one other unique identifier such as the patient’s date of birth or Health Card Number. Failure to provide this information may result in rejection or testing delay.

Special Instructions

Specimen should be transferred to the laboratory within 48 hours of collection.

Requisitions and Kit Ordering

Test Frequency and Turnaround Time (TAT)

Streptococcus pyogenes cultures are tested Monday to Friday.

Turnaround time for typing is up to 21 days from receipt by PHO laboratory.

Test Methods

Streptococcus pyogenes isolates are identified by MALDI-tof.

Isolates from invasive infections as well as outbreak specimens are forwarded to the Public Health Agency of Canada, Winnipeg for emm typing and emm Sub-Typing.


Results are reported to the ordering physician or health care provider as indicated on the requisition.

Specimens that are positive for invasive Streptococcus pyogenes Lancefield group A are to be reported as per Health Protection and Promotion Act.

contact lab

Contact Laboratory Customer Service

Laboratory Services

Updated 19 Nov 2020