THE INFECTION OF CHIMPANZEES WITH ECHO VIRUSES

Abstract

The oral and parenteral infections of chimpanzees receiving echo Types 6 and 4 viruses successively are described. The two infections, spaced 2½ months apart, and given by the same route in each animal, failed to induce overt disease. The inapparent infections were demonstrated by virus excretion in the throat and the stools and the development of neutralizing antibodies. Complement-fixing antibodies also appeared after Type 6 infection, but fell more rapidly than the neutralizing antibodies.