Twenty tigers and one panther dead after bird flu outbreak at Vietnam zoo

More than a dozen tigers have died after contracting bird flu at a zoo in southern Vietnam, according to officials.

State media VNExpress reported that a caretaker at Vuon Xoai zoo in Bien Hoa city said the animals had been fed raw chicken purchased from local farms.

One panther and 20 tigers, including several cubs, have been incinerated and buried on the zoo grounds. They weighed between 10 and 120 kilograms (20 and 265 pounds).

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Zoo manager Nguyen Ba Phuc said: "The tigers died so fast. They looked weak, refused to eat and died after two days of falling sick." Tests conducted on samples taken from the tigers confirmed they were positive for H5N1, the virus responsible for bird flu.

The virus was initially identified in 1959 and has since evolved into a widespread and highly lethal threat to migratory birds and domestic poultry. In recent years, H5N1 has been detected in an increasing variety of animals, including dogs, cats, sea lions, and polar bears.

In felines, researchers have discovered the virus attacking the brain, damaging blood vessels, causing seizures, and leading to death.

More than 20 other tigers are currently isolated for monitoring. The zoo is home to approximately 3,000 other animals, including lions, bears, rhinos, hippos, and giraffes.

The 30 staff members who were looking after the tigers tested negative for bird flu and were in good health, according to VNExpress. The newspaper also reported another outbreak at a zoo in the nearby Long An province, where 27 tigers and 3 lions died within a week in September.

Occasionally, unusual flu strains originating from animals are found in humans. US health officials announced on Thursday that two dairy workers in California had been infected, bringing the total number of cases detected in the country in 2024 to 16.

"The deaths of 47 tigers, three lions, and a panther at My Quynh Safari and Vuon Xoai Zoo amid Vietnam's bird flu outbreak are tragic and highlight the risks of keeping wild animals in captivity," PETA Senior Vice President Jason Baker told The Associated Press. "The exploitation of wild animals also puts global human health at risk by increasing the likelihood of another pandemic."

Bird flu has resulted in hundreds of deaths worldwide, with the vast majority involving direct contact between people and infected birds.