A car wreck on Interstate 59 in Mississippi on Tuesday afternoon gave a handful of lab monkeys their first taste of freedom. But after a multi-agency response and confusion over whether the animals were carrying several serious viral infections, only a few made it out of the ordeal alive.
The crash was reported at around 1:30 p.m. Tuesday just north of Heidelberg, where a truck hauling 21 rhesus macaques from Tulane University’s National Biomedical Research Center on the northshore hit a median and flipped, ejecting eight of the animals from their cages.
Although initial alerts issued by the Jasper County Sheriff’s Department claimed the “aggressive” monkeys were infected with herpes, COVID-19 and hepatitis C, Tulane University officials soon clarified that they were not infectious.
Jasper County Sheriff Randy Johnson told WDAM-TV Tuesday evening that five of the escapees were killed in the ensuing hunt and three remained on the loose. Thirteen monkeys that did not break out of their cages were recaptured.
The crash and subsequent killing of some of the monkeys garnered plenty of public attention, making national headlines and quickly becoming the butt of jokes online. It also sparked outrage among animal lovers and advocates near and far, thrusting Tulane’s controversial animal research center back into the spotlight.
But in the days since the monkeys escaped, authorities have left questions about the crash largely unanswered. It’s still unclear where the monkeys were headed and why some of them had to be killed, and the agencies involved have largely shut out attempts to get more information.
After Tulane officials publicly disputed Jasper County’s account of events, the Sheriff’s Department said in a statement posted to social media Tuesday evening that it was the truck driver who warned authorities the monkeys were dangerous and required personal protective equipment for handling.
“We took the appropriate actions after being given that information from the person transporting the monkeys,” the Sheriff’s Department said.
It has since declined to comment further.
Tulane spokesperson Michael Strecker said the university was not involved in the transport of the monkeys, does not own them and did not have custody of them when the truck carrying them to another unidentified facility crashed.
Strecker didn’t say who the monkeys belonged to or where they were headed, but he confirmed they had just left Tulane’s research center when the “tragic incident” occurred. Strecker said primates from the research center are often provided to other organizations to “advance scientific discovery.”
“This is a common practice among research organizations,” he said. Strecker referred further questions to the Jasper County Sheriff’s Department.
Tulane’s animals are used for medical research and federal law mandates that tests be conducted in animals before approval can be given for clinical trials involving people, according to Tulane.
The Mississippi Highway Patrol is leading an investigation into the cause of the crash. A spokesperson declined to comment further on Wednesday, referring questions about the monkeys to Tulane and the Mississippi Department of Wildlife, Fisheries and Parks.
People wearing protective clothing search along a highway in Heidelberg, Miss., on Wednesday, Oct. 29, 2025, near the site of a truck which overturned Tuesday, that was carrying research monkeys. (AP Photo/Sophie Bates)
Officials with the wildlife department said Wednesday they are coordinating with local authorities to hunt down the remaining monkeys and urged residents to avoid contact and report sightings by calling (800) BE-SMART.
Animal advocacy organization People for the Ethical Treatment of Animals has called for more answers, demanding the release of full necropsies and veterinary records. PETA’s Senior Vice President Kathy Guillermo said in a prepared statement that Tuesday’s ordeal exemplifies the risks of animal testing, particularly on monkeys, which she said often carry diseases that can be transmitted to humans.
“Terrified monkeys running for their lives into unprotected, populated areas is exactly the spark that could ignite the next pandemic,” she said.
Tony Goldberg, a professor at the University of Wisconsin School of Veterinary Medicine and a researcher specializing in cross-species disease transmission, said the macaques in question are not likely to cause the next COVID-19.
Native to Asia, rhesus macaques are the primates that have long been most commonly used in medical testing and research, Goldberg said. They’re about as big as a medium-sized dog and often live in close proximity to densely populated cities, where Goldberg said they interact with people largely without issue.
“So three monkeys on the run in Mississippi, I wouldn’t be alarmist about it,” he said.
Many macaques do carry a form of herpes, B-virus, that affects them in much the same way herpes impacts humans.
Though rare, Goldberg said B-virus can be spread to humans through biting or scratching and can enter the nervous system, causing serious illness or death. But Goldberg said the risk is low. Studies of monkey handlers and research personnel — Goldberg himself studies wild primates in Africa — show “very low” transmission rates.
“As the police proved,” Goldberg said, “we’re much more of a danger to them than they are to us.”
