Enterovirus 71 pathogenicity in monkeys and cotton rats.

Enterovirus 71 (EV71) is a neurovirulent non-polio enterovirus that can cause severe central nervous system (CNS) infection in infants. Vervet monkeys infected intracerebrally or intramuscularly with EV71 isolates from the Bulgarian outbreak of 1975 developed clinical manifestations and pathological signs of encephalomyelitis and spinal poliomyelitis that were similar to EV71 neuroinfection in children. In addition, vervet monkeys with encephalomyelitis had severe alterations in the choroid plexus. EV71 neuroinfection could also be reproduced in young (3- to 4-week old) cotton rats with clinical and pathological signs comparable with those observed in vervet monkeys.