Illegal Wildlife Trade Increases Interspecies Disease Risk

For every decade a species remains in the illegal global wildlife markets, the risk of interspecies disease increases, according to a new study published in Science on April 13, 2026.

The research, which analyzed decades of global wildlife trade data, found that 41% of traded mammal species carry at least one pathogen capable of infecting humans, compared to just 6.4% of non-traded species.

Each additional decade a species spends in wildlife markets corresponds to an average increase of one more human-infecting pathogen, indicating that prolonged trade actively amplifies disease risk over time rather than merely exposing humans to existing threats.

Colin Carlson, an epidemiologist at the Yale School of Public Health and co-author of the study, stated that the findings provide the strongest evidence to date that reducing wildlife trade will lower pandemic risk.

The study highlights that the danger is particularly pronounced in illegal markets and the exotic pet trade, where live animals are kept in close quarters, increasing opportunities for cross-species pathogen transmission.

Past outbreaks linked to wildlife trade include the 2003 mpox outbreak in the United States, traced to Gambian giant rats imported for the pet trade, and numerous Ebola outbreaks associated with bat handling for food or traditional medicine.

Although the study’s implications are primarily public health-focused, its findings resonate within entertainment industries that rely on exotic animals for film, television, and live performances, where close human-animal contact on sets heightens potential spillover risks.

The research underscores the need for stricter regulation of wildlife use in entertainment, particularly as global demand for authentic animal portrayals in media continues to drive both legal and illegal trade channels.