Characteristics of Herpes Zoster and Varicella Viruses Propagated in Vitro

Summary The agents of varicella and herpes zoster grown in cultures of human amnion retain infectivity only when associated with viable cells. Conditions which lead to cell death as measured by the eosin Y dye exclusion test result in concomitant loss of infectivity. Using a plaque assay method without agar overlay, the optimum conditions for virus absorption, propagation and release have been investigated. The preparation of cell-free infectious varicella virus from infected primary human thyroid cultures has been confirmed.