A study on the influence of papovavirus upon encephalitis caused by SSPE agent.

To investigate a possible interaction between the SSPE agent and papovaviruses, histopathological and statistical evaluations were made of encephalitis induced in hamsters by intracerberal inoculation with isolates from SSPE and PML patients, and with BK virus, alone or in combination. With SSPE virus alone, hamster brains showed a reduction of susceptibility to encephalitis with increasing age. A modification of the pathology of SSPE encephalitis was observed after administration of the PML isolate or BK virus: encephalitis was either enhanced or inhibited depending on the time the papovaviruses were administered. A possible mechanism of interaction between SSPE and papovaviruses is briefly discussed.