The state's first case of bird flu is in the Hunter. Here's what you need to know

Hundreds of government staff have converged on the Hunter after the state's first case of deadly bird flu was confirmed this week.

Preliminary test results had raised the alarm on Friday, July 3, prompting the NSW Agriculture Minister to trigger the state's bird flu response plan on Saturday night after the case was confirmed.

Farmers have been advised to house poultry and take extra biosecurity precautions, and the community has been told to be vigilant for signs of unusual wild bird deaths or sickness as the state and national response ramps up.

Officials have urged the public not to panic and offered reassurances that the state's agricultural sector was safe, supplies were unaffected, and the risk to humans was low.

The state had been preparing for the first case of the deadly H5N1 strain for some time, Agriculture Minister Tara Moriarty said at the weekend, and mitigation efforts were working effectively.

Authorities confirmed late on Saturday, July 4, that a sample taken from a migratory bird at Hawks Nest in Port Stephens had become a confirmed case after preliminary tests returned a presumptive positive on Friday.

It represents the sixth case in Australia after confirmations in Western Australia and South Australia last month.

Australia's chief veterinary officer Sam Hamilton said there was no evidence of mass mortality events resulting from the disease, and testing has failed to find cases in poultry or the domestic agricultural system.

"The risk to human health remains low," Dr Hamilton said.

Testing was ongoing over the weekend, but authorities have said the virus' detection was not a surprise.

While the virus could be deadly for animals, the risk to humans is generally considered low in terms of transmission and health impact according to the state's top vet, Jo Coombe.

Dr Coombe described the symptoms of the virus in humans as being similar to a common cold, adding there had been no recorded cases of human-to-human transmission.

Surveillance on land and in the sky via drone ramped up at the weekend in a large-scale response to control the event. The efforts were expected to continue over the coming weeks.

Some 500 additional state staff have converged on the region to assist the effort as part of the government's response, the minister said. They will coordinate with federal counterparts, Ms Moriarty added, as part of the broader national response plan.

The state took measures to reassure farmers and the community at the weekend, with Ms Moriarty saying preparations for the first case of bird flu on local shores had been under way for some time.

"The NSW government has been preparing for a positive result for some time and there is a clear plan in place to support industry and the community," she said.

"There is no impact on the supply of chicken meat or eggs and I would encourage everyone to purchase these products as they normally would."

"At this stage the result is limited to a single migratory seabird and has not impacted our poultry sector or domestic wildlife."

Ms Moriarty urged the community to avoid contact if they see unusual deaths or illness in wild birds, and to report such instances to the Emergency Animal Disease hotline on 1800 675 888.

The public has been urged to record locations and take photos as part the push for community vigilance.

Common signs of bird flu include wild birds that cannot stand, walk or fly properly; have a droopy or puffed-up appearance; appear to be panting or experiencing breathing problems; have an unusual head or neck posture; or die suddenly.

In mammals, including dairy cattle which have been most highly affected internationally according to the American Veterinary Medical Association, symptoms of low appetite, a sudden reduction in milk production, abnormal milk appearance, respiratory illness, lethargy, dehydration and fever.

Dr Coombe said the response over the weekend demonstrated the state's biosecurity system was working as intended.

"This confirmed case of H5N1 avian influenza in a giant petrel was detected as a result of our surveillance activities, which included increased awareness and advice to the public to report sick or dead birds or wildlife," Dr Coombe said.

"I thank the broader community, NSW government staff, the veterinary community, wildlife sector and our poultry industries who are all working together to detect cases early and avoid any onward spread."

Burnet Institute scientific director for research translation Professor Heidi Drummer said the Hunter case was significant, but there was no reason to panic.

The alarm was raised late this week after preliminary testing on samples taken from a migrating giant petrel. The species migrates annually along the Southern Ocean flyway from breeding grounds on sub-Antarctic islands and the Antarctic coast to Australia's subtropical waters between autumn and early spring.

The species in listed as vulnerable by the NSW Environment and Heritage Department, and are common to NSW waters.

Dr Drummer said careful surveillance and testing were crucial as authorities tried to determine whether the detections in migratory seabirds were isolated events or part of a broader pattern of virus movement in wild bird populations.

"It is important to be clear that detection in wild birds does not mean the virus is widespread in Australia, or that it has entered commercial poultry," she said.

The strain was first detected on the Australian mainland on June 14 in a brown skua found in Esperance, on WA's south coast.

The spread among migratory birds was "largely inevitable" but Australia was still doing "a very good job" of containing bird flu, Mater Health Services director of infectious diseases, Professor Paul Griffin, said.

Dr Griffin said it was now "only a matter of time" before further cases were detected in other states, and the impact on commercial bird populations could be devastating if large-scale culls were required.

"But we do have good protocols in place ... some of the largest producers have implemented more stringent measures to reduce that risk," he said.

Emma Grant, from La Trobe University's Institute for Molecular Science, said the virus could spread very quickly.

"It can also be quite severe in different animals, so what it means for the wildlife in Australia is yet to be seen," Dr Grant said.

This story includes reporting by AAP.