Abstract
Rhesus monkeys (Macaca mulatta) exposed to small-particle aerosols of the Aichi strain of type A2 influenza virus responded by shedding virus from the nasopharynx for 7 to 9 days and by seroconversion (hemagglutination inhibition) 8 or 9 days after exposure. After rechallenge with the homologous virus, no replication of the organism was observed, and a serological anamnestic reaction occurred. The data indicate that the rhesus monkey is a useful primate model for evaluating induced immunity to influenza virus infection.