Morphological characterisitcs of the pathological process in the central nervous system of monkeys infected with variants of measles virus strain L-16.

The neurovirulence of L-16 vaccine measles virus strains and its 9 clonal variants was investigated in intracerebrally infected Macaca mulatta monkeys. Two groups of clones were distinguished: one comprised variants that caused destructive changes of neurons in the brain and diffuse proliferative gliosis, and the second variants that caused changes of a transitory character, connected with the traumatic exposure.