Murrumbidgee Local Health District (MLHD) director of public health Tracey Oakman said residents should take extra precautions and protect themselves against mosquitoes following the detection of the mosquito-borne virus in mosquitoes and sentinel chicken flocks.

"In Griffith a few chickens have been found to have had seroconverted to Kunjin virus," she said.

"It means a mosquito has bitten it and it has been exposed to the virus, so we know that some mosquitos in the Griffith area must be carrying the virus.

"It is generally a mild disease and very rarely can become nasty.

"It is really rare, in fact I don't know of anyone around here who has ever had it."

Ms Oakman said mosquito numbers in Griffith were normally high and this season was no exception.

"There have been a high number of mosquitoes in our Griffith traps," she said.

"It's about now, late summer, that mosquitos have viruses.

"My message for residents is to be sensible and be really careful not to get bitten."

The majority of Kunjin virus infections do not show symptoms. However a small number of people develop mild illness with fever, enlarged lymph nodes, rash, swollen and aching joints, headache, muscle weakness and fatigue. Some people with Kunjin virus disease may develop encephalitis, a severe brain infection which may require hospitalisation.

Ms Oakman said people need to take steps to avoid mosquito bites including wearing protective clothing and repellent.

"You should also protect your home with screens and remove collections of water around the house where mosquitoes can breed," she said.

"The next few weeks will be ideal breeding conditions for mosquitoes which carry a range of human diseases like Ross River virus, Barmah Forest virus, Kunjin virus, and Murray Valley Encephalitis virus.

"Avoiding mosquito bites will be especially important now and until at least after Easter when many people may be enjoying outdoor activities such as camping or fishing in areas with high mosquito numbers."