As shown in Table I, 97 guinea pigs were used in this study. Fifty-seven were exposed by placing a virus suspension on their normal skins. Of this number, 34 had screw-top capsules attached to them. Thirteen were exposed by spreading the virus suspension on their feed and cage litter. Ten were inoculated intracerebrally to establish the potency of the virus. The remaining 17 were not exposed artificially to the virus and were employed as controls to detect cross infection.
Twenty-two guinea pigs, to which capsules were attached, died as a result of virus infection; 1 died of unknown causes and 11 survived without showing any clinical signs of the infection. Sixteen of the animals without the capsules died of virus infection and 7 did not become infected. The 10 guinea pigs that were inoculated intracerebrally became infected and died. None of the animals that were exposed by spreading the virus on the feed and the litter in the cages, or those used as unexposed controls, developed any clinical signs of infection with lymphocytic choriomeningitis.
It is realized that minute abrasions, not visible with a hand lens, may have been present in the skins of these guinea pigs. However, any condition of this nature would be a factor encountered in any normal skin.
In view of these facts, it is believed that these results indicate that the virus of lymphocytic choriomeningitis may infect guinea pigs through the normal, apparently intact, skin.