Conjunctival instillation of scrapie in mice can produce disease.

Mice were infected with one of two strains of scrapie by instilling brain homogenate into the conjunctiva to establish whether infection could be initiated. Of the 55 mice infected with ME7 scrapie, 23 developed clinical disease 323 +/- 8 (mean +/- standard error) days later. Three out of 12 mice infected with 79A scrapie developed disease after 232 +/- 35 days. The ME7 incubation period is similar to that for the oral route of infection. We feel that these results emphasize the need for adequate eye protection when handling tissues infected with spongiform encephalopathies.