Poxvirus infection in a rat (Rattus norvegicus) in Kuwait

A poxvirus was isolated from skin lesions on the tail of a rat (Rattus norvegicus) in Kuwait in February, 1982. The virus grew on the chorioallantoic membrane (CAM) developing chicken embryos and induced small generalized haemorrhagic pock lesions, 72 hours post-inoculation. It grew also with cytopathic effect (CPE) in CER and Vero cell lines. In cultured cells it produced cell rounding and syncytia 48-72 hours post-infection. The virus was resistant to the effect of ether as well as to chloroform, and showed haemagglutinating activity against chicken red blood cells in a low titer (1:16). It induced in the rabbit skin nodular lesions 4-5 days post-infection. Electron microscopy of the negatively stained preparations revealed brick-shaped typical poxvirus virions measuring 220-250 millmicron in diameter. By using vaccinia antiserum the virus antigen was precipitated in the agargel immunodiffusion test and this indicates its relation to the genus Orthopoxvirus.