Survey for Pneumocystis carinii infection of wild-born and laboratory-bred monkeys by indirect immunofluorescence and cyst-staining methods.

A serosurvey for Pneumocystis carinii infection of laboratory-bred and wild-born monkeys was made by the indirect immunofluorescence method. The antibody titers of wild cynomolgus (Macaca fascicularis) and Japanese monkeys (Macaca fuscata fuscata) to P. carinii (Pc) were higher than those of laboratory-bred cynomolgus monkeys; 54.9% of the wild cynomolgus and 40% of Japanese monkeys had antibody titers higher than 1:40, although only 9.4% of the laboratory-bred cynomolgus monkeys did so. Pc cysts in the lungs were examined in the laboratory-bred cynomolgus monkeys by using toluidine blue O stain, and the number of cysts in the lung was small, when compared with those in the lungs of SIV-infected monkeys showing severe pneumosystosis. The results obtained from the studies suggested the possibility that P. carinii infection was more widely epidemic in the wild-born monkeys than in laboratory-bred monkeys.