Detection of varicella-zoster virus DNA in throat swabs of patients with herpes zoster and on air purifier filters

Zoster patients are considered to be less contagious than those with varicella because their infectious lesions are localized. However, it is not known when the spread of varicella-zoster virus (VZV) from zoster patients begins, how long it continues, and how far the virus spreads from the zoster patients. Twelve cases of hospitalized zoster patients were studied. The polymerase chain reaction (PCR) was used to detect VZV DNA in samples taken from the surface of their eruptions, throats, and the air purifier filters in their rooms. In all patients, VZV DNA was detected in the samples from eruptions. VZV DNA was detected in 8 of 12 patients from the throats. VZV DNA was detected for 9 of 12 patients from the filter samples. This study shows the possibility of a wide distribution of VZV DNA to the environment from infected patients. VZV may be excreted from cutaneous eruptions or from the throats of patients.