Update: Evaluation of Captive Gibbons in North American Zoological Institutions for an Epizoonotic Agent: The Gibbon Ape Leukemia Virus (GALV)
The gibbon ape leukemia virus (GALV) is an infectious gammaretrovirus associated with neoplasias in gibbons. Highly related retroviruses have been isolated from other animals (woolly monkey, koalas).1-4 The virus is shed in urine, feces, and saliva and can be transmitted in utero and via postnatal contact. Since its initial characterization in the 1970s and 80s, the incidence of GALV has not been assessed in gibbons. Investigating the disease status of captive animals as well as factors affecting their health is a critical first step in determining if captive gibbons are infected, and if an etiologic linkage between infection and neoplastic diseases exists. Diagnostic assays developed and validated with National Zoological Park animals (PCR of genomic DNA, co-culture for virus isolation, and ELISA) were used to identify the presence or absence of viral DNA, RNA, and GALV antibodies in 80 captive gibbons representing 29 zoological institutions in North America. Samples were obtained during routine and diagnostic examinations. Studies revealed possible exposure to GALV, but lack of integration or expression of the virus.
The authors thank the members of the primate team, Department of Animal Programs at the National Zoo for their care of these animals, and the medical technologists in the Department of Pathology for their assistance.
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