Diagnosis of acute and latent varicella-zoster virus infections using the polymerase chain reaction.

A simplified assay for the diagnosis of varicella-zoster virus (VZV) infections based on the polymerase chain reaction (PCR) is described. Omitting the procedures for extraction and purification of DNA, the crude vesicle fluid materials were used for PCR. Moreover, hybridization was not necessary for detection of the amplification products because they were already visible after ethidium bromide staining of the electrophoresis gel. Results could therefore be obtained within one day. In comparison to virus isolation, PCR proved much more rapid, highly sensitive, and specific. DNA extraction and a double PCR assay with nested primers were necessary for detection of latent VZV infections in trigeminal and thoracic ganglia. The data suggest that the procedures described are universally applicable to several types of specimens dependent on the calculated amount of target DNA.