Recovery of a new herpesvirus from the ground squirrel (Citellus citellus).

A new herpesvirus recovered from the kidneys of mature ground squirrels (Citellus citellus) produced an effect in tissue culture cells resembling that of herpesviruses, including the formation of multinucleated syncytia and type A intranuclear inclusions. The isolate caused latent infection in the natural host, but it proved fatal for intracerebrally inoculated suckling mice and it produced pocks on the chorioallantoic membrane of embryonated eggs. Electron-microscopic examination of infected cells revealed intranuclear virus particles exhibiting a size and ultrastructure characteristic of herpesviruses. The isolate was ether-resistant and a DNA nucleic acid type was inferred from observations on inhibition by fluorinated pyrimidine. This ground squirrel herpesvirus was found to be antigenically distinct from Herpesvirus hominis and from ground squirrel cytomegalovirus, with no detectable cross-reactivity.