Respiratory – Virus

Testing Indications

Public Health Ontario Laboratories (PHOL) utilizes different testing algorithms for influenza and other respiratory viruses during the winter and summer seasons.

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 and time of year.

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. Failure to provide this information may result in rejection or testing delay.

Place specimen container in the biohazard bag and seal bag, and insert the completed requisition in the pocket on the outside of the sealed biohazard bag. Specimens should be stored at 2-8°C following collection and shipped to PHO laboratory on ice packs.

Special Instructions

Follow the instructions found in the Virus-Respiratory Kit Instruction Sheet.

Test Frequency and Turnaround Time (TAT)

Respiratory virus testing is performed daily Monday to Saturday.

The Turnaround time (TAT) for the Direct Antigen Test for Influenza is within 1 day after receipt.

The TAT for Influenza A/B PCR and MRVP 1 is up to 2 days after receipt by PHO laboratory.

The TAT for rapid respiratory virus culture (R-Mix TOO) is up to 4 days.

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 for adenovirus from Outbreaks are reported to the Medical Officer of Health as per Health Protection and Promotion Act.

Algorithm

Public Health Ontario laboratories utilizes different testing algorithms for influenza and other respiratory viruses during the winter and summer seasons.

The winter algorithm usually takes effect the first Monday of November and remains in effect until the first Sunday of May. 

The summer algorithm usually takes effect the first Monday of May and remains in effect until the first Sunday of November. 

Exact effective dates may vary due to influenza activity in the community during the transition time periods.

Influenza testing available at PHO laboratory (summer and winter). 

Table Footnotes

1. Patient setting must be provided to help triaging of specimens. If patient setting is not provided, sample will NOT be tested.
2. ICU - Intensive Care Unit; CCU - Critical Care Units.
3. MRVP1 detects: influenza A, influenza A H3 subtype, influenza B, respiratory syncytial virus (RSV) A and B. 
4. Timmins testing site will use Flu A/B RT PCR until subsequent implementation of MRVP1.
5. For outbreaks with special concerns, including requests for additional testing, contact PHO Laboratory’s Customer Service Centre.
6. Specimens that are positive for influenza A and negative for H3 using MRVP1 will be subsequently tested for influenza A (H1N1) pdm09 subtype.
7. The Rapid Viral Culture system (R-Mix Too©) detects:  adenovirus, influenza A, influenza B, respiratory syncytial virus (RSV), parainfluenza 1, 2 and 3, and human metapneumovirus.
8. CMV PCR for bronchoalveolar lavage (BAL)/bronchial wash/pleural fluid will be done if requested on the requisition.
9. Respiratory swab collection kits will not be supplied for these patient settings.
10. To assist with patient management 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 (see 5 below).

Labstracts

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