In May 2020, a plane full of monkeys, intended for COVID-19 research, was supposed to depart Mauritius. But it never did. So, who purchased the monkeys? What lab was their final destination? When Jackie Flynn Mogensen began to investigate why the flight didn’t take off as planned, she discovered a whole lot more about the wider trade of primates, and how a shortage of monkeys for research leads to serious issues, from stalled research and drug testing in many high-priority areas to an increase in the smuggling of animals.

By the fall of 2020, monthly monkey imports had returned to their 2019 levels, thanks to large increases in supply from Cambodia and Mauritius—and since have largely stabilized. And last year, despite zero monkeys coming from China, the US managed to import more than 31,000 monkeys in total, just 8 percent less than imports in 2019. But this has hardly meant a return to normalcy in the US. Keep in mind that while the total number of imports may have recovered, the entire world is fighting a pandemic. On top of the demand for studying HIV, or malaria, or cancer, or an endless number of other research areas, two years ago a never-before-seen virus swept across the planet. And we needed monkeys to fight it.

For fields outside of Covid, like Alzheimer’s, Parkinson’s, and heart disease, the low monkey supply has been “devastating,” Roberts adds.

Cheri Lucas Rowlands

Cheri has been an editor at Longreads since 2014. She's currently based in the San Francisco Bay Area.