Epizootic of parainfluenza-3 virus infection in gibbons.

A laboratory-housed breeding colony of white-handed gibbons (Hylobates lar) experienced an epizootic of upper respiratory tract disease characterized by lethargy, anorexia, coughing, and serous rhinorrhea. Signs were more severe in adults than in offspring, and all animals recovered without complications. Base-line, acute, and convalescent sera from the most severely affected gibbons were tested for antibodies against a wide spectrum of infectious agents. For personnel known to have had contact with the gibbons, testing for the same agents was done on base-line sera and sera obtained at the same time as the acute and convalescent sera were obtained from the gibbons. Rising titers against parainfluenza-3 virus were detected in 6 of 7 gibbons tested. An increase in titer was not seen in the sera of personnel.