Avian influenza has been detected at an egg farm on the northern fringes of Greater Sydney, the first time the virus has been found in New South Wales in 11 years.
The virus at the farm in Hawkesbury was identified as the H7N8 strain – different from the outbreaks of the H7N3 and H7N9 strains first detected in Victoria one month ago.
Officials believe the high-pathogenicity virus likely came from infected wild birds.
The outbreak may cause some localised supply disruptions, the egg industry said, but added there is no shortage of eggs or safety concerns around eating eggs or poultry products.
“These new cases of avian influenza will cause further disruption to egg supply in some areas, but we’re still a long way from a collapse in supply,” said Rowan McMonnies, the managing director of peak body Australian Eggs.
“The natural threat of [avian influenza] is ever present and the next few months will be challenging for Australian egg farms, but the industry will continue to work hard to ensure there’s eggs on shelves.”
Tara Moriarty, the NSW agriculture minister, said in a statement on Wednesday the outbreak is a “separate spillover event” from the Victorian cases and believed to be the result of contact with infected wild birds.
Moriarty said the government had triggered its emergency animal disease response, locking down the affected farm to prevent the movement of equipment and animals. A control order will extend biosecurity controls to a radius of one to two kilometres around the property.
The farm will be “depopulated”, meaning all chickens will be euthanised and disposed of to prevent further spread.
She said the government would “work closely with industry to reduce the risk of spread and minimise any impact on egg supply”.
Australia takes a zero tolerance approach to all strains of high-pathogenicity avian influenza, meaning all birds on an infected property, from commercial egg farms to back-yard flocks, must be destroyed.
More than one million chickens and ducks have already been euthanised as a result of the outbreak in Victoria, which has spread to seven poultry farms.
Genomic sequencing of the viruses, conducted at the CSIRO’s Australian Centre for Disease Preparedness in Geelong, found the two strains identified in Victoria, H7N3 and H7N9, can be traced back to a common strain 12 months ago.
Dr Joanne Sillince, the acting chief executive of the Australian Chicken Growers Council, said the laboratory had done a “stupendous” job in quickly identifying strains.
“There’s a level of cooperation, that’s the big difference between [this outbreak] and the last one,” Sillince said. “That takes a lot of the anxiety out of it for producers because you know that as soon as something happens you are going to be told about it.”
Various strains of avian influenza are present in the wild bird population in Australia, and are particularly spread by wild ducks, which fledge in late summer.
McMonnies said wild birds in Australia were “dishing up a tough winter for Australian egg farmers”.
“Our systems provide for early detection as the critical first step in getting on top of [avian influenza] outbreaks and the industry will continue to support NSW as we step through the process,” McMonnies said.
The H7N3 strain of the virus was detected at an egg farm at Meredith in Victoria on 22 May and has since spread to five other egg farms and one duck farm in the immediate area. The H7N9 strain was detected at a property at Terang 130km away, which was linked through contact tracing to the first farm at Meredith. A control order has been issued to mandate that all birds within a 20km and 15km radius, respectively of the affected farms be kept indoors or otherwise away from contact with wild birds.
A spokesperson for NSW Farmers said the organisation is working with the Department of Primary Industries to ensure primary producers have the support they need.
“Our focus is on biosecurity for all farmers with poultry, including rapid identification and containment, to help safeguard the health and safety of our birds,” they said.
They urged anyone with poultry or other birds, including back yard chooks, to report any symptoms, which include fever, respiratory distress and sudden death, to the Emergency Animal Disease hotline on 1800 675 888.
