Biosecurity Queensland is quarantining a property in Cairns, Queensland, Australia, after a horse returned an initial positive test for hendra virus infection. At least five people were exposed to the horse before he died.
Queensland Chief Veterinary Officer Rick Symons, BVSc, MBA, PhD, said the horse was sick on July 25 when it was seen by a private veterinarian.
"The horse was sampled yesterday and results have come back today as positive," he said. "The horse died (July 27). Tracing is being conducted to indentify other animals that may have come into contact with the deceased horse.
On July 28, Symons said Biosecurity Queensland officers had spent the day on the property assessing how many other horses may have been exposed.
"There have been quite a few other horses moving on and off the site in recent weeks," he said. "We are conducting tracing of these horses and speaking to the owners."
Hendra virus has been known to yield numerous clinical signs in horses including respiratory distress, frothy nasal discharge, elevated body temperature (above 40°C, or 104°F), and elevated heart rate; however, authorities caution that hendra infection does not have specific signs. The disease is zoonotic, meaning it can be transmitted from horses to humans, and as proved deadly for several humans exposed to sick horses in the past.
The Australian Veterinary Association suggested that horse owners can reduce the risks of hendra virus in their horses by fencing off trees attractive to flying foxes (a type of fruit bat thought to spread hendra to horses), covering horse feed and water containers, and not feeding horses food that could appeal to flying foxes, such as fruit and vegetables.
Queensland's Chief Health Officer Jeannette Young, MB, BS, FRACMA, FFPH, said to date, public health experts had identified five people who had contact with the infected horse near Cairns.
"Public health staff have conducted thorough assessments today and all contacts have had a low level of exposure to the sick horse," Young said. "We acknowledge that these are difficult circumstances for these people. Our public health staff will continue to consult with them to ensure they are provided with all the information and support they require.
"I can also confirm that the woman assessed as having a high level of exposure to a horse infected with hendra virus near Rockhampton, remains in a stable condition," Young said. "The patient does not have any symptoms of hendra virus infection. The patient does not wish any further information be released at this time."
The Cairns case is the sixth hendra virus incident in Queensland this year. One property at Rockhampton and two properties near Mackay remain under quarantine after recent confirmed cases of hendra virus infection.