A sixth person has been diagnosed with Japanese encephalitis in NSW.

The confirmed case is a man in his 60s from the Balranald area in the Riverina region, who is being treated in a Victorian hospital.

NSW Health is urging the community to stay vigilant and take precautions against mosquito bites.

Several more people in NSW are undergoing further testing for the virus, which is spread by mosquitoes and can infect animals and humans.

The virus cannot be transmitted between humans and cannot be caught by eating pork or other pig products.

There is no specific treatment for JE, which can cause severe neurological illness with headache, convulsions and reduced consciousness in some cases.

The best thing people can do to protect themselves and their families against JE is to take steps to avoid mosquito bites.

NSW Health recommends:

* Avoid the outdoors, bushland and wetlands at peak mosquito times - dawn and dusk

* Wear long sleeves and pants, socks and shoes

* Use insecticides (e.g. permethrin)

* Use and reapply repellent (e.g. DEET, picaridin, or oil of lemon eucalyptus)

* Use mosquito nets for children, and mosquito coils

* Empty and reduce all water-holding containers around your house.