A newly released study in the journal Science indicates that approximately 41% of wild mammal species involved in the global trade for food, furs, scientific research, and traditional medicine carry at least one pathogen capable of causing diseases in humans.
This work, conducted by an international team of scientists, marks the first quantitative analysis of the role of wildlife trade in the spread of infectious agents, reinforcing the urgent need for stricter controls to prevent global disease outbreaks.
The study highlights that various historical outbreaks of diseases in humans have origins in the wildlife trade. Examples include the emergence of HIV, the Ebola epidemic in West Africa in 2014, and the COVID-19 pandemic, which swept the world starting in 2020.
Arinjay Banerjee, a virologist at the University of Saskatchewan in Canada, emphasizes that the transmission of viruses from animals to humans is not new, but the innovation of this research lies in the precise measurement of the scale of this phenomenon, providing concrete data to support public policy.
Comprehensive records on pathogens in wildlife trade have only begun to be systematically compiled in recent years, driven by the COVID-19 crisis. This allowed Jérôme Gippet, an ecologist at the University of Fribourg in Switzerland, to lead a team that correlated animal trade with the prevalence of pathogen-carrying mammals.
According to Gippet, the results provide the first global quantitative evidence that wildlife trade significantly amplifies the risks of zoonoses, diseases transmitted from animals to humans.
The analysis combined four decades of data from three major wildlife trade databases with a 2021 information bank developed by ecologists investigating the origins of COVID-19. The focus was on mammals, which represent about a quarter of globally traded species and have a notable history of pathogen transmission.
Out of a total of 2,079 mammal species analyzed in trade, the team’s models indicate that 41% share at least one pathogen with humans, a rate much higher than the 6.4% observed among non-traded mammals.
The researchers developed predictive models that assess the risks of pathogen spread through commercial interactions, considering variables such as the evolutionary history of species, proximity to human communities, consumption as food, and use in scientific experiments.
An alarming finding is that the trade of live animals, rather than derived products, significantly increases the likelihood of transmission. Additionally, the duration of a species’ presence in trade also influences: with each decade of commercial circulation, a species tends to share, on average, one additional pathogen with humans. Illegal trade, meanwhile, plays a smaller but still relevant role in this risk scenario.
Jérôme Gippet expresses hope that the findings will guide the creation of more effective regulations in wildlife trade, focusing on preventing new epidemic outbreaks. For additional details on the research, further information can be accessed on the Science website, where the study was originally published.
With information from nature.com.
Original published at O Cafezinho.