Detection of varicella-zoster virus DNA in blood of children with varicella.

The nested polymerase chain reaction was used to detect varicella zoster virus (VZV) DNA in 67 samples of peripheral blood mononuclear cells (PBMC) from 39 otherwise healthy children with varicella. Eleven were during the incubation period and 56 were after appearance of rash. VZV DNA was detected in two of eight (25%) PBMC at the early phase of the incubation period (day -14 to -11). The rate of the detection increased to 67% in -5 to -1 days prior to the onset of the rash and 46% in 0-4 days after the onset. It declined gradually with time and was undetectable in patients after 15 days from the clinical onset. The serum antibody determined with the fluorescent antibody to membrane antigen was first detected in the samples on day 2 and subsequently increased to 100% rapidly. In conclusion, VZV DNA cannot be detected usually in PBMC of healthy children except in varicella.