Epidemiologic Studies of Latent Virus Infections in Captive Monkeys and Baboons1

From February through December 1966, a total of 365 pairs of sera were collected from rhesus and green monkeys and baboons while they were kept in captivity. Both rhesus and green monkeys showed a low rate of SV5 and parainfluenza 3 virus infections at the time of arrival at the local laboratories as determined by the neutralization tests, but showed an average conversion rate of 30% to parainfluenza 3 and 50% to SV5 during 30–90 days of quarantine. None of the 193 paired sera tested showed antibody titers to either parainfluenza 1 or parainfluenza 2. On the other hand, both rhesus and green monkeys, as well as baboons, showed a high incidence of group A influenza anti-s antibody titers, but no inhibition could be demonstrated when these sera were tested against PR8, FM1, Jap/305/57, Taiwan/1/64, and swine viruses. The specificity of the influenza A anti-s titers in monkey sera is under investigation.