Experimental poliomyelitis in bonnet monkey. Clinical features, virology and pathology.

We have investigated the distribution of virus and the pathology in the spinal cords of bonnet monkeys (Macaca radiata) with experimental paralytic poliomyelitis induced by inoculating poliovirus type 1 (Mahoney) into the right ulnar nerve. Viraemia and alimentary tract infection due to the inoculated virus were found in all monkeys. Between two and seven days after the onset of limb paralysis, the animals were killed and the spinal cord examined. Virus was isolated from the cervical enlargement, thoracic region and lumbar enlargement in titres ranging from 10(2.5) to 10(6.4) TCID50/gram of tissue. Cellular infiltrate, perivascular cuffing, early and late neuronal damage such as chromatolysis, nuclear pyknosis, retraction of the cytoplasm and neuronophagia were seen distributed throughout the spinal cord. This experimental animal model resembles human paralytic poliomyelitis clinically and pathologically.