A Poxvirus of Primates. I. Growth of the Virus In Vitro and Comparison With Other Poxviruses 2

A primate poxvirus (OrTeCa) isolated from a skin lesion in a rhesus monkey (Macaca mulatta) was studied along with four known poxviruses: vaccinia, monkeypox, swinepox, and Yaba. It grows in established lines of monkey kidney cells at a rate intermediate between that of vaccinia and monkeypox and that of swinepox and Yaba. The cytopathic effects produced by OrTeCa virus resemble those produced by swinepox virus, although, unlike swinepox, it cannot be propagated in porcine cells. Neither can OrTeCa be grown in rabbit kidney or chick embryo cells or on chick chorioallantoic membranes, all of which support the growth of vaccinia and monkeypox viruses. OrTeCa forms plaques about the same size as those of Yaba and swinepox viruses, but they appear earlier; they are morphologically similar to the plaques of vaccinia and monkeypox viruses. The thermal stability of OrTeCa is about the same as that of vaccinia and monkeypox but greater than that of Yaba virus.