Seroepidemiologic survey of captive old‐world primates for antibodies to human and simian retroviruses, and isolation of a lentivirus from sooty mangabeys (Cercocebus atys)

Abstract

Sera from 526 Old-World monkeys and apes, representing 50 species and 20 genera and living in US zoos and vivaria, were screened for antibodies to HTLV-I, HTLV-III/LAV, and simian-AIDS retrovirus, type I (SRV-I). Sera were screened initially by ELISA, and ELISA-positive sera, as well as ELISA-negative sera from cage contacts, were further tested by Western blotting. A large number of false-positive and a small number of false-negative ELISA sera were identified. Although most true positive reactions were directed to a single retrovirus, a number of individuals from 4 species were positive for more than one retrovirus. Specific seroreactivity to HTLV-I was found in 39/526 (7%) animals of 15 species. True positive reactions to SRV-I were found in 21/516 (4%) animals, including talapoins and 2 species of macaques. Specific serologic reactions to HTLV-III/LAV were detected in 23/526 (4%) monkeys. Many of the HTLV-III/LAV seropositive animals were from one mixed-species zoo exhibit, containing sooty mangabeys, mandrills, Kolb's guenons, and talapoins. A type D virus was isolated from the blood of 3/10 SRV-I antibody-positive Tonkeana macaques, but from none of 11 seropositive talapoins. A lentivirus was isolated from the blood of 4/7 HTLV-III/LAV seropositive sooty mangabeys, but not from seropositive talapoins in the same exhibit or from 2 seropositive colobus from another zoo. The sooty mangabey lentivirus produced generalized lymphadenopathy, leukopenia, and decreased levels of T4 lymphocytes in 2 experimentally infected rhesus macaques.

Simian Retrovirus Infections: Potential Confounding Variables in Primate Toxicology Studies

“…The natural hosts of SIV include many species of African monkeys and the chimpanzee (Pan troglodytes) (11,35,49,52). Prevalence of infection in various populations of captive and wild African primates may exceed 50% (11,49).…”

“…Prevalence of infection in various populations of captive and wild African primates may exceed 50% (11,49). Infection in these natural host species, however, is almost always subclinical (11,35). Asian macaques are susceptible to SIV infection, but naturally acquired (i.e.…”

“…Asian monkeys of the genus Macaca, which represent the majority of primates currently being used in toxicologic research, are natural hosts for 3 of these viruses (SRV, SFV, STLV) (5,35). Retrovirus infections represent extraneous variables in research protocols.…”

Biology and Pathogenesis of Lentiviruses

“…It is closely related, genetically and antigenically, to HIV-2. Limited serological surveys have shown no evidence that the virus occurs in nature in the Asian habitat of these animals (Lowenstein et al, 1986;Ohta et al, 1986). The first description of SIVmac was by investigators at the New England Primate Center in Massachusetts, who identified the lentivirus during studies on experimentally transmitted lymphomas of rhesus monkeys (Macaca mulatta) (Hunt et al, 1983).…”

Monographs on the Evaluation of Carcinogenic Risks to Humans

“…The first primate 1entivirus to be identified was SIV MAC at the New England Regional Primate Research Center following an outbreak of Iymphoma in rhesus (Macaca mulatta) and cynomoIgus macaques (Macacafascicularis) (Daniel et al, 1985). SIV MAC is not naturally found in Asian macaques (Macaca mulatta) (Lowenstine et al, 1986;Wu et al, 1991), but Its close reIationship to SIVsMM can be expIained by the introduction of SIV sMM-infected mangabeys into primate centres in the United States during the late 1960s and subsequent transfer of SIV into macaques. Each SIV appears to be endemic to the respective monkey species and none has yet been associated with disease in the natural host (Gardner et al, 1994).…”