Horses in Thailand are now being vaccinated with the hope of protecting them from African horse sickness. | Photo: Courtesy TheHorses Endurance Stable, Thailand

As veterinarians rush to vaccinate Thai horses against the deadly African horse sickness (AHS) virus, the outbreak continues to create a path of destruction, said local officials. With a death toll now standing at 463 horses, AHS is spreading east and west from its initial outbreak site in central Thailand.

More than 400 of the deaths have been recorded in the Nakhon Ratchasima province, where veterinarians first identified the disease following the sudden death of 40 horses in the province’s Pak Chong District last month. An additional 62 horses have died as of April 28, as the disease has progressed southwestward into provinces along the Gulf of Thailand toward Malaysia and eastward toward Cambodia, the Thai Equestrian Federation reported.

Meanwhile, vaccination programs began April 19, according to government reports to the World Organisation for Animal Health (OIE) in Paris. The first horses to receive vaccines were the animals used in the snake venom and rabies antidote development center of the Thai Red Cross Society in the Phetchaburi province. Although the center is 350 km (217 miles) from the initial outbreak site, the 560 Red Cross horses received priority vaccination because of their role in human medicine