Immunohistological localisation of rinderpest virus in formalin-fixed, paraffin-embedded tissues from experimentally infected cattle.

Six Freesian steers were subcutaneously inoculated with the virulent rinderpest virus strain Kabete "0" and sacrificed at the height of fever. Sections of formalin-fixed, paraffin-embedded tissues were stained according to the peroxidase anti-peroxidase (PAP) technique. Labelling of viral antigen, both in the cytoplasm and in the nuclei of infected cells, was observed in the epithelial cells of the upper and lower alimentary tract and in lymphoid organs, i.e. spleen, lymph nodes, pharyngeal tonsils, Peyer's patches and thymus. Electron microscopy studies confirmed the results.