Human Varicella-Zoster virus (VZV)

Test code: S0035 - Qualitative detection of human Varicella-Zoster virus by polymerase chain reaction

Varicella (chickenpox) and zoster represent different clinical manifestations of infection with the same agent, varicella-zoster virus (VZV). Varicella occurs most frequently in children and is characterized by a generalized vesicular exanthem often accompanied by fever. Zoster (shingles) usually occurs in adults or immunocompromised patients (including those with AIDS) and consists of a painful, circumscribed eruption of vesicular lesions with accompanying inflammation of associated dorsal root or cranial nerve sensory ganglia. Varicella is the primary infection with VZV, whereas zoster is a secondary infection due to reactivation of latent VZV in sensory ganglia.

VZV is a member of the Herpesviridae. The genomic size is approximately 125 kb. The genome can exist in four different isomeric forms.

Nonhuman primates, such as the common marmoset, Callithrix jacchus, have been shown to be capable of being infected with human varicella-zoster virus (Provost et al., 1987). This observation is not surprising as simian varicella-zoster virus and human varicella-zoster virus share a high degree of genomic similarity and antigenicity (Felsenfeld and Schmidt, 1979; Gray and Oakes, 1984). The outbreak of human varicella virus infections in captive monkeys is of concern as the potential exists for contact between monkeys and human carriers of this virus.

Serological detection of VZV infection is not very reliable, sensitive or specific. VZV detection by PCR is the most rapid, sensitive and specific method for the diagnosis of this infection.

Utilities:

• Confirm the disease causing agent
• Ensure that animal colonies are free of VZV
• Early prevention of spread of this virus among a colony
• Minimize personnel exposure to this virus
• Safety monitoring of biological products and vaccines that derive from primates

References:
Felsenfeld, A.D. and Schmidt, N.J. (1979) Varicella-zoster virus immunizes patas monkeys against simian varicella-like disease. J. Gen. Virol. 42:171-178.
Gray, W.L. and Oakes, J.E. (1984) Simian varicella virus DNA shares homology with human varicella-zoster virus DNA. Virology 136:241-246.
Provost, P.J., Keller, P.M., Banker, F.S., Keech, B.J., Klein, H.J., Lowe, R.S., Morton, D.H., Phelps, A.H., McAleer, W.J. and Ellis, R.W.(1987) Successful infection of the common marmoset (Callithrix jacchus) with human varicella-zoster virus. J. Virol. 61:2951-2955.

Specimen requirement: 1 ml whole blood in EDTA (purple top) or ACD (yellow top) tube, or lesion swab or lesion scab, shipped overnight at room temperature.

For specimen types other than those listed here, please call to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodologies: Qualitative PCR

Normal range: Nondetected