The marmosets Callithrix leucocephala (E. Geoff.) and Callithrix jacchus (L.) and the lion marmoset Leontocebus rosalia (L.) were found to be susceptible to infection with yellow fever virus.
In C. jacchus and L. rosalia, death in general did not supervene following inoculation with the Asibi or French pantropic strains; the virus circulated in the blood and neutralizing antibodies subsequently appeared. Most of the South American jungle strains, however, were highly lethal for these species.
In C. leucocephala, on the other hand, fatal infections were produced not only by the jungle strains but also by the Asibi strain, the only African strain tested. The average survival time of animals infected with the Asibi strain, however, was greater than that of animals infected with the South American strains.
Specific liver lesions were found in all three species of marmosets following fatal infection with yellow fever virus. These are described and compared with the lesions produced by the virus in the liver of man and rhesus monkeys. Differences between the types of lesions produced in L. rosalia on one hand and in C. jacchus and C. leucocephala are described and discussed.
Marmosets which survived infection with any of the African or South American strains developed a humoral immunity.