Collecting Specimens for Varicella Zoster Virus (VZV) Testing

Refer to the Infectious Disease Laboratories Test Directory entry for each test, see links below, for instructions on acceptable specimen types, specimen collection, storage, and shipment as well as points of contact for testing at CDC using VZV-specific serologic assays.

Varicella Zoster Virus (VZV) Serology (Test CDC-10255)

Refer to the Infectious Disease Laboratories Test Directory entry for each test, see links below, for instructions on acceptable specimen types, specimen collection, storage, and shipment as well as points of contact for VZV PCR testing at CDC.

• Varicella Zoster Virus Detection (Wild-type vs. Vaccine) – (Test CDC-10254)

To make a laboratory diagnosis of VZV infection using polymerase chain reaction (PCR) method, the presence of the virus DNA should be demonstrated in tissues, vesicular fluid, maculopapular lesions, or crusts from lesions. The following methods are recommended.

Polyester Swab Method

(best suited to sampling vesicular lesions)

Guidelines

1. A sterile needle should be used to unroof the top of the vesicle.
2. A sterile swab† is then used to vigorously swab the base of the lesion— applying enough pressure to collect epithelial cells without causing bleeding—and collect vesicular fluid. It is important to collect infected epithelial cells from the base of the lesion because they usually contain a significant amount of virus.
   †We recommend swabs made from synthetic fibers, such as polyester, because it is difficult to elute virus from cotton swabs, and wooden swab supports usually absorb extraction buffer and inhibit PCR.
3. Swabs must be placed individually into separate, empty tubes to avoid contamination. Place swabs directly into tubes. Tubes must be individually labeled and must be resistant to breakage.
4. Swabs can also be placed in 0.5 – 1.0 mL of viral transport media.
5. See Handling and Shipping PCR Specimens for shipping instructions.

Glass Slide Method

(This method is critical for the collection of material from maculopapular lesions)

Guidelines

1. Rake the edge of the slide over the selected lesion, abrading the lesion with sufficient vigor to ensure that skin cells are gathered onto the slide. Use a sterile polyester swab to scrub the abraded lesion and (using the same swab) collect the material collected on the edge of the slide. Note: with young children, it may be less stressful if you ask them to help with this. If more than one lesion is sampled, a separate swab should be used for each one.
2. Insert the swab into a tube and close it (many swabs are provided with a tube that includes a label for marking the specimen).
3. Ship in a padded envelope. The swab for each sampled lesion must be placed in a separate swab tube, but multiple tubes can be shipped in the same envelope.
4. See Handling and Shipping PCR Specimens for handling and shipping instructions.

Collecting Crusts (Scabs)

Whenever present, crusts are excellent samples for PCR detection of VZV DNA. Crusts can be lifted off the skin (a glass slide is also useful for this purpose) and transferred directly into break-resistant, snap-cap or screw-top tubes. See Handling and Shipping PCR Specimens for shipping instructions.

Collecting Other Specimen Types

For some disease presentations with a suspected VZV etiology (e.g., meningitis, multi-focal organ damage), samples of cerebral spinal fluid (CSF), blood, biopsy, or autopsy tissue may also be shipped. See Handling and Shipping PCR Specimens for handling and shipping instructions.

Handling and Shipping PCR Specimens

Refer to the Infectious Disease Laboratories Test Directory entry for each test, see links below, for instructions on acceptable specimen types, specimen collection, storage, and shipment as well as points of contact for VZV testing at CDC.

• Varicella Zoster Virus (VZV) Serology (Test CDC-10255)
• Varicella Zoster Virus Detection (Wild-type vs. Vaccine) – (Test CDC-10254)

In rare cases involving severe complications or death, other types of specimens (e.g., biopsied or autopsy tissue, cerebrospinal fluid, peripheral blood, etc.) may be sent to the National VZV Laboratory for PCR testing.

Address for shipping specimens