Offering insight that may help in developing planned measures to curtail future pandemics, a new paper shows that one-quarter of mammal species in wildlife trade host 75% of diseases known to transfer between animals and humans.
The paper, ‘Mammals, wildlife trade and the next global pandemic’ by wildlife trade and infectious diseases researchers from the Ashoka Trust for Research in Ecology and the Environment (ATREE), in collaboration with The Nature Conservancy (TNC), was published in the journal Current Biology .
Researchers surveyed the association of 226 viruses responsible for zoonotic diseases with more than 800 mammal species distinguished into three categories: traded, non-traded, and domesticated mammals. Rodents and bats were previously identified as the significant players for disease transmission. The study also added primates and even-toed ungulates such as deer (often poached for their meat) and carnivores to the hot list. It shows that primates, bats, ungulates, and carnivores alone host 58% of the known zoonotic viruses present in the wildlife trade.
The study now provides empirical evidence for the strong association between wildlife trade and zoonotic disease risks, said Sandeep Sen of ATREE, one of the co-authors.
“It is important to survey and monitor groups that have high zoonotic virus richness. Other than bats, it is primates, carnivores, ungulates and rodents. These groups may likely harbour more undiscovered zoonotic viruses. One-quarter of the mammals in the wildlife trade harbour about 75% of known zoonotic viruses, which is alarming. What this means is that we need to monitor and curtail trade in a very large number of species,” said Mr. Sen.
The authors also acknowledge the threats posed by ongoing deforestation, land-use change, and habitat fragmentation which result in direct contact and disease transmission between humans and the species listed in their study. “Strong policy measures are needed for curtailing and monitoring wildlife trade,” added KN Shivaprakash of the TNC, the lead author of the study who heads the research project. Asked about remedial measures, Mr. Sen said, “In a way, it is simple. Curtail deforestation and fragmentation of habitats; increase connectivity of natural habitats..”
Kamal Bawa, another co-author and the president of ATREE, said the one health component of the National Mission on Biodiversity and Human Wellbeing, proposed the establishment of surveillance sites to prevent outbreaks of infectious diseases. Such sites, he said, could also be used for pathogen surveillance in confiscated wildlife specimens.