NSW Health has reported a new suspected case of Mycobacterium chimaera infection.
In a media statement issued on Tuesday the Department said the suspect case is in a person who underwent open-heart cardiac surgery at Prince of Wales Hospital in 2015, the same hospital involved in the two confirmed NSW case reported last year.
In January 2017 two NSW patients, one a woman in her 80s and one a man in his 40s, both of whom had undergone open-heart cardiac surgery at Prince of Wales Hospital in 2015, were confirmed to have developed the infection.
This brings the total number of confirmed cases to three, in addition to an earlier confirmed case in Queensland.
According to NSW Health, it may be some time before the infection in the suspect case is confirmed or excluded because of the slow-growing nature of the organism.
International reports of an outbreak of M. chimaera infection associated with contaminated heater cooler units used for cardiac bypass surgery started surfacing around August last year.
Related story: Cardiologists advised to be alert for rare infection
The TGA has said it is conducting a product safety review into all seven brands of heater-cooler devices supplied in Australia.
There have been three reports to date of confirmed M. chimaera in unused ParaTherm Heater/Cooler units supplied to Queensland Health. A fourth unit has reportedly also been contaminated but the bacterium is yet to be confirmed, the TGA revealed.
The regulator said it is considering whether regulatory action is required.
According to the TGA, the case fatality rate is about 50% but early detection of M. chimaera appears to result in better patient outcomes
Reported infections overseas include surgical site infection, endocarditis, prosthetic valve infection, para-valvular abscess, graft infection and myocarditis.
Some patients have presented with non-cardiac disease including granulomas, osteoarthritis, cholestatic hepatitis, nephritis, splenomegaly, or ocular disease.
Patients undergoing heart valve surgery, particularly with prosthetic implants, are considered to be at highest risk.
But the TGA advised that in appropriately selected patients, the benefits of temperature control necessary during open chest cardiothoracic procedures outweigh the risk of infection transmission associated with using these devices.