Respiratory Viruses (including influenza)

Testing Indications

Public Health Ontario Laboratory (PHOL) utilizes a testing algorithm for influenza and other respiratory viruses.

Refer to the current labstract on respiratory viral testing titled: LAB-SD-121 (Respiratory Viral Testing Algorithm) for detailed information about the testing method that will be performed based on patient setting.

Preparation Prior to 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.

Place the specimen container in the biohazard bag and seal the bag; insert the completed requisition in the pocket on the outside of the sealed biohazard bag. To maintain optimal viability of the virus, specimens should be stored at 2-8°C following collection and transported to PHO on ice packs within 72 hours of collection. If longer storage/transit time is anticipated, specimens should be frozen at -70°C or lower and transported on dry ice.

Special Instructions

Complete all fields of the PHO General Test Requisition Form: include the requesting healthcare provider's CPSO#, complete mailing address, telephone, and fax number, and the patient’s full name, date of birth, Health Card Number (must match the specimen label). Failure to do so may result in rejection or testing delay.

Test Frequency and Turnaround Time (TAT)

Respiratory virus testing is performed daily Monday to Saturday.

The TAT for the Direct Antigen Test for Influenza is within 1 day after receipt.

The TAT for multiplex respiratory virus PCR (MRVP) is up to 3 days after receipt by PHO Laboratory.

Samples tested by traditional virus culture are observed for a minimum of 17 days prior to reporting a negative culture result; samples that are positive can be observed at any point during this period.

TAT for traditional virus culture is up to 18 days.

TAT will vary during the winter months.

Reporting

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

Specimens that are positive from Outbreaks are reported to the Medical Officer of Health as per Health Protection and Promotion Act.

Public Health Ontario Laboratory (PHOL) utilizes a testing algorithm for influenza and other respiratory viruses which is based on patient setting.

Respiratory virus testing is available at PHOL according to the following table:

Table footnotes:

1. Patient setting must be provided on the requisition to help triaging of specimens. If patient setting is not provided, the specimen will NOT be tested.
2. ICU - Intensive Care Unit; CCU - Critical Care Units.
3. MRVP detects: Panel 1: influenza A, influenza A H3 subtype, influenza B, and respiratory syncytial virus (RSV NA/B); Panel 2: parainfluenza (1 – 4), adenovirus, enterovirus and influenza A H1 (pdm09) subtype; Panel 3: Seasonal human coronavirus (OC43, 229E, NL63, HKU1), rhinovirus and human metapneumovirus.
   Note: The assay detects the different RSV, parainfluenza  and season human coronaviruses listed but does not differentiate between them.
4. CMV PCR is available upon request (indicate on the requisition) for bronchoalveolar lavage (BAL)/bronchial wash/pleural fluid.
5. A limit of 4 outbreak specimen are routinely accepted for testing. For outbreaks with special concerns, including requests for additional testing, contact PHO Laboratory’s Customer Service Centre.
6. Respiratory virus swab collection kits will not be supplied for these patient settings.
7. To assist with patient management, in particular when respiratory virus testing is not available, healthcare providers are encouraged to refer to PHO’s respiratory surveillance reports for information on respiratory pathogen activity in Ontario.

Labstracts

LAB-SD-121 (Respiratory Viral Testing Algorithm and Enhanced Surveillance - Update)