Varicella zoster virus PCR

Diagnostic Use

Varicella zoster virus causes both latent, asymptomatic and symptomatic infections. During primary infection shedding can occur from sites other than the primary lesion, similarly during reactivation virus shedding may occur in the presence or absence of symptoms.

Diagnostic testing is helpful when clinical diagnosis is uncertain (especially immunocompromised individuals), where atypical lesions are present or when antiviral therapy is contemplated.

Department

Microbiology - Virology

Delphic Registration Code

Swabs = HERP; CSF = CNSP; Other samples (eg Tissue/Aspirate) = DVAR

Synonyms

Chicken pox
Herpes zoster virus
Shingles
VZV

Turnaround Time

3 days

Test Code

2321

Specimen Type

• Tissue
• Aspirate
• Fluid
• Swab - see Additional Information

Specimen Requirements

Tube/Container Type:

Preferred

• Swab - Viral

Acceptable

• Pottle
• Syringe

Pre-testing Requirements

Please consult laboratory if urgent.

Additional Specimen Information

Lesion, ulcer and vesicle swabs:
It is optimal to collect specimens within three days of eruption. Specific Syphilis and Herpes PCR collection packs are available from CHL patient services (email: Labinfo@cdhb.health.nz). These contain a dry swab with 80mm breakpoint and standard viral transport fluid tube.
Disrupt/remove top of vesicle, and collect fluid with tip of swab. With the same swab rub the base of the lesion, ulcer or open vesicle. Place swab in routine virology transport media and snap at breakpoint. Ensure cap is firmly tightened in place to prevent leakage and place in biohazard transport bag. Return the swab to the Laboratory. DO NOT place in bacterial transport medium (other acceptable transport medium is Green top viral transport swab if standard viral media not available, or a dry swab).

For non-vesicular lesions it is recommended that cells be collected from the base of the lesion using a swab pre-moistened with sterile saline prior to taking.

See link to Swab Guide under Additional Information section below.

Tissues:
Place small samples into virus transport medium to prevent drying. Place bigger specimens into a sterile container.

Deliver to lab as soon as possible.

Aliquot Instructions

Transport to Lab

Chilled (2 - 8 degrees Celsius)

Additional Referral/Aliquot Information

Place specimen in PCR bag.

Interpretation

Varicella zoster virus causes both latent, asymptomatic and symptomatic infections. During primary infection shedding can occur from sites other than the primary lesion, similarly during reactivation virus shedding may occur in the presence or absence of symptoms.

Diagnostic testing is helpful when clinical diagnosis is uncertain (especially immunocompromised individuals), where atypical lesions are present or when antiviral therapy is contemplated.

Results are reported as Varicella zoster virus DNA DETECTED or Varicella zoster virus DNA NOT detected.

PCR results should always be interpreted in conjunction with clinical history or symptomatology.

For additional clinical interpretation contact the Clinical Microbiologist or Microbiology Registrar via Virology. Phone 03 3640356 (x80356) or 03 3640354 (x80354).

Test Method

Detection of VZV DNA. Nucleic acid extraction, PCR amplification and detection.

Contact Canterbury Health Laboratories on +64 3 364 0484 or email LabInfo@cdhb.health.nz

Diagnostic testing for Varicella zoster virus (VZV) is very helpful when a clinical diagnosis is uncertain (especially in immunocompromised individuals), where atypical lesions are present or when antiviral therapy is contemplated.
These assay can be used for the detection of VZV nucleic acid from all samples and sites.
Nucleic acid testing by PCR for VZV has an increased sensitivity and provides improved turn around time compared to virus culture. PCR is now the diagnostic test of choice for Varicella zoster virus, and has replaced antigen detection and culture at CHL.

Testing Strategy:
Where possible the referrer needs to indicate the site and virus of interest. This will help the laboratory rationalise what testing is needed. For example genital sites will be tested for Herpes simplex viruses (HSV) I & II. Cutaneous sites will be tested for Varicella zoster virus (VZV) first and then for HSV if clinically indicated. Samples from oral and lip lesions will be tested for HSV. Often HSV and VZV skin infections are clinically indistinguishable.

Resources

• Swab Guide

Contact Information

Enquiry Form