CHAING MAI – A field veterinarian has raised new concerns about the real cause behind the deaths of 72 tigers in Chiang Mai province. The questions came after the Livestock Office released a written statement saying lab tests found no genetic material of Influenza A. Instead, the report cited CDV (canine distemper virus) and Mycoplasma spp.
Still, the veterinarian says several details don’t add up. The tigers were kept at two separate sites about 30 kilometers apart, yet they became sick and died with similar symptoms.
In his view, the strongest shared factor was their food, which came from the same source, but he says officials barely mentioned it. He also warned that blaming one or two diseases could turn into a way to “pick a diagnosis” and hide a bigger problem, especially when it could affect high-value livestock industries.
What happened at the private tiger park
The case involves tigers at a well-known private tourist attraction in Chiang Mai. Reports say the animals began showing signs of illness between February 8 and February 18, 2026. The deaths gradually increased, reaching a total of 72.
During the incident, the facility closed temporarily. Staff also disinfected areas and allowed relevant government agencies to inspect the site.
On February 21, 2026, the Livestock Office Region 5 issued its explanation. The statement said the Upper Northern Veterinary Research and Development Center’s lab tests did not detect Influenza A.
However, it reported finding genetic material consistent with CDV and Mycoplasma spp. The statement also noted possible transmission routes, including blood-sucking vectors, contact through bites and blood exposure, and mother-to-offspring transmission.
Even so, many people continued to question the explanation. Some pointed out that the tigers lived in a controlled setting with strict hygiene measures. The animals were also not all housed together because they were kept in separate enclosures.
In addition, observers found it unusual that tigers at Mae Rim and Mae Taeng, two locations about 30 kilometers apart, fell ill and died in the same way.
The veterinarian’s on-site observations
On February 22, 2026, Dr. Visit Arsaithamkul (Wisith Asai-thamkul), a former veterinarian with the Zoological Park Organization of Thailand and part of the on-site veterinary team from the beginning, shared his views on Facebook (Visit Arsaithamkul).
He said he felt uneasy about disease surveillance and outbreak management, especially with the public debate growing. He then summarized what he saw and why he believes the case needs a wider look.
He described the first signs as lethargy, loss of appetite, and fever. After that, some tigers developed seizures and died quickly.
According to him, necropsies on the first group of deaths (within 1 to 2 days after symptoms began) did not show obvious severe lesions. Because of that, the team considered several possibilities early on, including viruses, toxins, and bacteria.
He said the main puzzle was how tigers in both Mae Rim and Mae Taeng could get sick and die with the same pattern, despite being separated by about 30 kilometers. As he saw it, the most obvious common factor was diet.
He stated that more than 200 tigers across both sites ate the same food product, which came from a single source and was linked to a livestock-based supply chain. He added that nearly all tigers that ate this food showed illness, while three cubs that were still on milk did not.
As the days went on, he said the number of sick and dying tigers continued to rise. Since test results were not available right away, suspicion of a viral cause increased, and samples were sent to both university labs and government diagnostic centers.
How the team managed the remaining tigers
Because many tigers were still alive, he said the team grouped them into five categories: no symptoms, mild illness, moderate illness, severe illness, and critical illness or death. Each group received different care plans. He mentioned supportive and emergency treatments such as immune support, fever reducers, anti-seizure medication, and antibiotics.
He said university testing later supported a specific viral cause. After that, the team avoided necropsies on later deaths to reduce risk. He added that the group continued working with veterinarians from the Department of National Parks on evidence checks and carcass disposal.
He also pushed back on rumors about improper use of tiger carcasses, saying those claims were unfair and driven by bias.
Dr. Visit wrote that he understands the pressure to prevent damage to livestock industries worth tens of billions, even when compared with losses in the tiger operation. Still, he warned that sweeping the issue under the rug means the system learns nothing.
He tied this to the bigger One Health idea, where animal health, wildlife health, human health, and the environment are closely linked. He said he couldn’t accept pushing blame onto a convenient target while the real cause may remain and could strike again.
He ended by criticizing what he described as selecting a disease to serve as a scapegoat, arguing that it could harm trust in the veterinary profession both in Thailand and internationally, and that the truth would eventually come out.
