| Abstract: | The pathogenesis of mouse hepatitis virusâ‚„ (MHV-4) was studied in weanling specific pathogen-free mice using light, fluorescent and electron microscopy. Mice were inoculated intranasally with 0.03 ml. of a 15% (w/v) brain homogenate which contained 5,630 MLD[subscript 50's] of MHV-4 virus. Control mice were inoculated in a similar manner with non-infectious control inoculum. Gross lesions consisted of discrete white foci on the surfaces of the livers of infected mice. Histologic lesions were detected in the lungs, thymus, lymph nodes, intestine, spleen, liver, brain, eyes, spinal cord, and stomach respectively. The lesions were characterized by interstitial pneumonia, lymphoid necrosis and focal areas of necrosis in the intestine, stomach, and eyes. Hepatic lesions were characterized by multiple focal areas of necrosis. Histologic lesions in the brain were characterized by meningitis, focal to diffuse necrosis in the gray matter and status spongiosus in the white matter. Similar changes were seen at various levels in the spinal cord. ... |
|---|