People who reported hunting or butchering wild animals in rural areas in Cameroon volunteered to collect blood samples from wild animals that they had hunted.Hunters were educated about the risks associated with direct contact with wild animals and about appropriate prevention measures.
Our team had absolutely no control over the species selected by hunters, and also worked closely in the field with staff from the Cameroonian ministry responsible for wildlife to ensure that it was clear to hunters which species were protected and should not be hunted.Likewise, phylogenetic analysis has demonstrated that at least three of the four major HTLV lineages, HTLV-1, HTLV-2 and HTLV-3, originated from multiple introductions of their simian virus counterparts in monkeys and apes, STLV-1, STLV-2, and STLV-3, respectively.Thus, STLV and HTLV lineages are called primate T-lymphotropic viruses (PTLVs).All protocols were developed in partnership with and with guidance from leading conservation organizations, including the Wildlife Conservation Society, the University of California Davis and Eco Health Alliance (formerly, the Wildlife Trust) to ensure the highest ethical standards as we conduct trainings and build wildlife surveillance capacity.Specimen collection from captive and wild animals was approved by IACUC and the Cameroon government.Through detailed examination of SIV infections in over 45 NHP species, it has been demonstrated that HIV-1 arose from multiple cross-species transmissions of SIVcpz and SIVgor from chimpanzees and gorillas, to people in west Central Africa.
Many studies have described ongoing zoonotic infection of primate workers, hunters and butchers with SFV from a variety of monkeys and apes and phylogenetic analysis showing that the co-evolution of SFV with NHPs has facilitated accurate identification of the simian origin of infection.
Given the demonstrated pandemic potential of retroviruses, a full understanding of the epidemiology and animal reservoirs of zoonotic primate retroviruses is of importance for monitoring and preventing future retrovirus pandemics.
The primate origin of these zoonotic infections has been identified by detailed epidemiological and phylogenetic analyses of both human and non-human primate (NHP) retroviruses.
Specimen collection from captive and wild primates was approved by the University of Johns Hopkins Animal Care and Use Committee (FS03M221 and FS06H205), University of California Institutional Animal Care and Use Committees (IACUC) (ARC#2007-110-01A, ARC#2007-110-2, ARC#2007-110-3), the University of California Davis IACUC (Protocol #16067) and the Cameroon government.
All sample collections from captive primates were undertaken by veterinary animal care staff (authors Babila Tafon and John Kiyang) in the Limbe Wildlife Centre and Mfou National Park (wildlife rescue centers) during immobilization as part of quarantine health checks, regular health checks or during transport between enclosures.
Our findings shed further light on the importance of gorillas as keystone reservoirs for the evolution and emergence of human infectious diseases and provide a clear course for preventing HTLV-4 emergence through management of human contact with wild gorillas, the development of improved assays for HTLV-4/STLV-4 detection and the ongoing monitoring of STLV-4 among gorillas and for HTLV-4 zoonosis among individuals exposed to gorilla populations.