Varicella Zoster Virus Detection
Submission and Collection Notes
Samples requesting VZV will be tested by an in-house multiplex HSV1 and 2/VZV PCR method.
VZV molecular typing is available to differentiate between wild type and vaccine strains of VZV. Resistance testing is also available when clinically indicated. Specimens submitted for either of these tests are initially cultured at the PHO laboratory prior to submission to National Microbiology Laboratory (NML), Winnipeg, for further testing.
Please refer to VZV genotyping of wild-type strain and vaccine strain.
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 in biohazard bag and seal. Specimens should be stored at 2-8°C following collection and shipped to the PHO laboratory on ice packs. If transport is delayed for more than 72 hours store at -80˚C prior to shipping.
Follow the instructions found in the Virus-Culture Kit Instruction Sheet.
Complete all fields of the General Test Requisition Form. Include, the patient’s full name, date of birth, Health Card Number (must match the specimen label), enter the name of the test requested under test description, source of specimen, date of onset, date of collection, physician name and address, and clinical diagnosis.
Test Frequency and Turnaround Time (TAT)
Varicella Zoster virus PCR testing is performed daily Monday to Friday. TAT is up to four days.
Samples tested by culture are observed for a minimum of 14 days prior to reporting a negative culture result; samples that are positive can be observed at any point during this period. TAT for virus culture is up to 16 days after receipt.
Contact the PHO laboratory Customer Service Centre to request typing or resistance testing or refer to: NML guidelines: VZV genotyping of wild-type strain and vaccine strain.
Results are reported to the ordering physician or health care provider as indicated on the requisition.
Specimens that are positive for Varicella Zoster virus are reported to the Medical Officer of Health as per Health Protection and Promotion Act.
As of August 6, 2019, virus culture will no longer be performed for VZV detection. Specimens will be tested for HSV1/HSV2/VZV at PHO - Toronto laboratory using a more sensitive in-house real-time multiplex PCR method.