Two new retroviruses—the type of virus which causes AIDS—have jumped from non-human primates to people, a new study reveals.
The study of blood samples from nearly a thousand bushmeat hunters or handlers in Cameroon showed that at least six viruses had crossed from monkeys to the people who were exposed to freshly caught bushmeat. And two of these viruses have never been seen before in humans.
The newly discovered human T-cell lymphotropic virus 3 (HTLV-3) and HTLV-4 are closely related to the known viruses, HTLV-1 and HTLV-2. These are implicated in cancers like leukaemia and can cause inflammatory or neurological diseases.
Retroviruses such as HTLV or HIV insert their genetic material into a host cell’s DNA. The emergence of HIV is widely blamed on a primate retrovirus, SIV, jumping to humans. Previously, it was thought that the emergence of these viruses was limited by the rarity of successful cross-species transmission.
“What’s increasingly clear is that the hunting and butchering of non-human primates is associated with the transmission of retroviruses to humans,” says Nathan Wolfe, at the Johns Hopkins Bloomberg School of Public Health in Baltimore, US, who led the study.