Victoria’s Chief Health Officer, Brett Sutton, has announced today the detection of Japanese encephalitis virus (JEV) in pigs in the Echuca area (see attached link). Evidence of the virus has also been found in pigs in New South Wales and in southern Queensland. Attached is a more detailed discussion on JEV published by the World Organisation for Animal Health (OIE) for those who are interested.
Wild water birds act as a reservoir for the virus. Pigs play an important role as virus amplifiers. Mosquitoes spread the disease. Horses (and humans) can become infected but are considered to be ‘dead end hosts’ (animals that can become infected but are not able to transmit the organism to a different host).
The disease is often fatal in humans who develop clinical symptoms. Infected horses can also get very sick, with many dying. Like Murray Valley Encephalitis (a related disease) most infected horses are asymptomatic or have mild symptoms.
Evidence of JEV has been detected in the Torres Straight Islands since the 1990s. The fact that it has arrived on the mainland is no surprise. It could become an established disease particularly in parts of Australia with year-round mosquito activity and feral pigs.
I understand that there is a vaccine for humans, pigs and horses, but it’s not currently available in Australia.
It’s much too early to predict the impact, if any, of the detection of JEV in eastern Australia on the harness racing industry. I anticipate that the focus of work by State veterinary authorities in coming weeks will be on gaining a better understanding of the extent of distribution of the virus. Some countries to which horses are exported could potentially also raise concerns about the JEV status of horses awaiting export.
Potential for Japanese encephalitis infections in Victoria | health.vic.gov.au
