Cytological, cytochemical and immuno-fluorescence studies with Dugbe virus - a new Nigerian tick-borne virus

Dugbe virus, a new tick-borne arbovirus from Nigeria, was propagated in continuous porcine kidney (PS) cells, and the cytopathology studied by various staining techniques such as May-Grunwald-Giemsa, methyl-green pyronine, Feulgen, and immuno-fluorescence. The gross cytopathology was slight and infected cells continued to undergo normal mitotic divisions. The outstanding cytopathologic feature was the presence of large basophilic intracytoplasmic inclusion bodies, which were pyroninophilic and Feulgen negative. By immunofluorescence these inclusions were shown to be depots of viral antigen; specific fluorescence was confined to the cytoplasm throughout the replication of the virus.