St Vincent's Hospital is screening patients for a superbug that can kill up to half the people it infects, after the bacteria was discovered in an elderly patient who had surgery there six months ago.

St George's Health Service in Kew - a St Vincent's rehabilitation and aged care facility - is also on alert because the patient, Renee Scott, is now being cared for there in a single room with strict infection control procedures.

Mrs Scott, 81, is carrying the antibiotic resistant bacteria called Carbapenem Resistant Enterobacteriaceae (CRE), a relatively new superbug that is fuelling grave concern in Australia about a post-antibiotic era. The bacteria can colonise a person's bowel or skin without harming them, but if it causes an infection, there are very few antibiotics that can treat it, if at all. Infections with the bacteria carry a death rate of about 50 per cent.

A St Vincent's spokesperson confirmed the case but would not reveal whether other cases had been found at the hospital since June last year, when it first revealed dozens of its patients had been affected by the bacteria since 2012.

Mrs Scott had her hip replaced during surgery at St Vincent's Hospital in Fitzroy in November and her family is angry it did not know about previous CRE cases.

Daughter Diane Rojek said her mother had suffered ongoing infections since November, including a urinary tract and chest infection, as well as a weeping wound from her hip surgery.

On Thursday, the St Vincent's spokesperson said although the particular strain of CRE found inside Mrs Scott had not been associated with sickness in the medical literature to date and was not causing Mrs Scott's ongoing sickness, staff were trying to prevent the bacteria from spreading to other patients.

The spokesperson said Mrs Scott was being cared for in a single room and that people entering the room are being asked to wear protective clothing. She said St Vincent's hospital staff detected CRE in Mrs Scott through a screening program for the superbug. Screening is occurring at other Victorian hospitals, too.

Ms Rojek said the hospital was doing a good job of caring for her mother, but that she wanted more transparency around superbugs.

"It's been horrific," she said. "I don't want anybody else to go through this."

In a written statement, St Vincent's infectious diseases expert Professor Kumar Visvanathan said other patients and their families should not be concerned because extensive testing at St George's had not found any other cases.

The new case came as Australia was invited to join a global, multibillion-dollar fight against superbugs which are predicted to kill more people than cancer if left unchecked.

On Wednesday, Britain's Treasury secretary Jim O'Neill said a an 18-month review into antimicrobial resistance found that superbugs could kill 10 million people a year by 2050 – more than cancer kills today.

It prompted Britain's chancellor, George Osborne, to call on finance ministers from around the world to agree on a common approach to fighting the threat of superbugs – antibiotics-resistant bacteria. It could include big new taxes on any pharmaceutical companies that don't work to find new antibiotics.

A spokeswoman for the federal department of health said while the British report echoed many strategies already under way in Australia, the government could not commit to implement its recommendations ahead of the election.

"These will be for the consideration of the new government," she said.

In June last year, Victorian hospitals were ordered to update their infection control procedures when it was discovered that a particular type of CRE known as KPC had been spreading between patients for the first time in Australia, mainly at St Vincent's hospital facilities in Melbourne. The hospital said several patients had died with the bacteria inside them and that it may have contributed to the death of two patients.

Professor Ben Howden, a microbiologist and infectious diseases physician at the Doherty Institute, said CRE had become a priority class of superbug globally because they were resistant to Carbapenems - antibiotics that have traditionally been viewed as "last resort" drugs.

This meant doctors often used potentially toxic antibiotics that could damage people's kidneys, with no guarantee of success.

He said people who are already sick, and who have been treated with many antibiotics, are most at risk of a CRE infection.