A sample from the Betta Maid bakery in Unanderra on the NSW South Coast has tested positive for the rare salmonella strain implicated in the outbreak at Canberra and Illawarra aged care homes which has claimed two lives.
The Illawarra Retirement Trust centres, where the vast majority of the cases have emerged from, has a centre which has been affected by the outbreak at Belconnen.
The NSW Food Authority confirmed on Wednesday an environmental sample had returned positive for salmonella bovismorbificans – the strain found in all 31 infected patients.
A spokeswoman said the Food Authority had collected a variety of product and ingredients, as well as equipment and environmental swabs from Betta Maid which supplied bakery products to the affected facilities.
Bakery products from the business were withdrawn from these facilities on the afternoon of February 17.
On February 25, results for a number of environmental and food samples taken from the bakery returned positive for salmonella species, the spokeswoman said.
"Further testing was undertaken to determine if the salmonella type was the same strain that was implicated in the outbreak or a different type of salmonella," the spokeswoman said.
"Four environmental samples have been returned with one returning positive to the strain of salmonella bovismorbificans that was also detected in affected residents."
The three other samples are being tested to determine the type of salmonella.
The spokeswoman said eight food samples supplied by the bakery to affected facilities had also returned positive results for salmonella and were "awaiting final typing to a particular strain".
There have been no reports of illness in the wider community related to consumption of food from the bakery.
Subsequent product samples the Food Authority has tested from the bakery were negative.
As a result of the positive salmonella result the NSW Food Authority is now undertaking further investigations.
The spokesman said the Food Authority was unable to comment further while the investigation was "open and ongoing".
To date, 31 cases of confirmed salmonella have been reported from 10 aged care facilities in the Illawarra, south-east Sydney and the ACT.
At least three of these cases have been in the ACT at IRT's Kangara Waters property in Belconnen.
NSW Health said the positive findings reported by the NSW Food Authority on Wednesday were consistent with the pattern of salmonellosis observed to date.
NSW Health is continuing to work with the affected aged care facilities to monitor and investigate any gastrointestinal illness among residents or staff, noting that the incubation period for salmonella can range from five to 20 days in some situations.
Betta Maid was unable to be contacted for comment.
With Primrose Riordan.