NT Health

Japanese encephalitis risk in the NT

7 April 2022

NT Health is urging Territorians to stay vigilant and take precautions against mosquito bites after evidence of the Japanese encephalitis virus (JE) was detected in a small number of feral pigs in the West Daly region. 

Since the first fatal JE case occurred in early 2021 on the Tiwi Islands, there have been no further cases in people in the Northern Territory. However, recently JE has been confirmed in multiple people interstate, including in New South Wales, Queensland, South Australia and Victoria, as well as at a number of piggeries.

Nina Kurucz, Director of the Medical Entomology Unit, NT Health, said JE is a serious disease spread by mosquitoes that can infect humans and animals, such as pigs, some birds and horses.

“JE cannot be transmitted from human to human, or by eating meat from an infected animal,” Ms Kurucz said.

“JE infection in humans is most commonly asymptomatic but, on rare occasions, it can result in severe disease and even death. Symptoms can include fever, headache, neck stiffness, vomiting, confusion, seizures and paralysis.

“People who believe they may be infected with the JE virus should seek urgent medical assistance.”

In response to recent cases interstate, JE surveillance has increased in the NT, expanding on an ongoing program which commenced following the fatal case recorded in the Territory last year.  

To date, all mosquito samples tested in NT have been negative for JE.

The NT Chief Veterinary Officer, Dr Sue Fitzpatrick, said that as the Territory has no commercial piggeries, free, voluntary testing is being undertaken on domestic pigs registered through the property identification code (PIC) system by staff from the Department of Industry, Tourism and Trade (DITT).

“Pig owners are asked to be highly vigilant for signs of this disease and report unexplained pig miscarriages or stillbirths or neurological signs in young piglets. Horse owners are also asked to report any cases of neurological signs to their local vet for investigation, and hunters should be on alert for signs of JE in feral pigs,” Dr Fitzpatrick said.  

“DITT is working with landholders who have had JE detected in feral pigs on their property.

“JE is a notifiable disease. This means animal owners and hunters should report suspicious or unusual signs in animals to the Emergency Animal Disease Watch hotline on 1800 675 888.”

Samples are also being taken from feral pigs in partnership with the Australian Government’s Northern Australia Quarantine Strategy staff.

While there is no specific treatment for JE, a vaccine is available. It is important to take steps to avoid mosquito bites, such as: 

• Wear protective light-coloured clothing with long sleeves, long trousers and socks in areas where mosquito bites are likely;
• Avoid outdoor exposure near wetlands and flooded areas, especially after sundown;
• Use a protective repellent containing DEET, picaridin or oil of lemon eucalypt (PMD) and other mosquito protection devices;
• Ensure infants and children are adequately protected against mosquito bites;
• Consider insecticide barrier treatments by pest control companies for use around residential grounds;
• Ensure windows and doors have screens to prevent mosquitoes from entering houses.

More information about JE and the current outbreak is available on the Australian Government Department of Health website.

Further details about JE in animals, including signs of the disease, are available online at: nt.gov.au/japanese-encephalitis

Media Contacts:

Russel Guse 0436 933 810 (NT Health)

Jessica Tapp 0409 640 859 (DITT)