An investigation is underway after a patient at the Royal Alexandra Hospital died after picking up a "multi-drug-resistant bacteria" believed to have been brought to the city from an overseas traveller.

The unidentified patient died within the last ten days and there are questions surrounding the cause of death.

It appears the patient died after coming in contact with antibiotic-resistant bacteria. Investigators are trying to determine if it is the same strains brought into Canada by a woman who had been travelling overseas.

The female traveler, who had to undergo surgery while overseas, came back with an infection in a surgical wound.

She was admitted to the Royal Alexandra Hospital about six weeks ago with the infection.

The woman was not immediately isolated upon being admitted, which is against hospital policy.

She was treated for three days before it was discovered that she had been infected by two types of bacteria overseas - one called acinetobacter and the other containing a group of genes called New Delhi metallobetalactamase or "NDM" that allows bacteria to become resistant to multiple antibiotics.

"Really what that means is we may have a limited number of antibiotics to treat infections that may be caused by this type of bacteria," said Dr. Mark Joffe, AHS senior director of infection, prevention and control.

Once the bacteria were discovered, intensive screening took place at the Royal Alexandra Hospital.

More than 400 patients were screened, while staff at the hospital closed various units and also stopped admitting new patients to the unit.

"We've been extremely aggressive in our approach to controlling these bacteria," Joffe said.

Officials say a health care worker did not follow proper procedures when dealing with the female traveler.

"I suspect that there was at least one opportunity for cleaning their hands that must have been missed," Joffe said.

Two patients at the hospital are confirmed to have picked up the bacteria containing NDM.

Two other patients have picked up the acinetobacter.

Investigators are still trying to determine if another two patients – including the one who has died – contracted the same strain of drug-resistant bacteria brought back by the female traveler.

Joffe says it won't be known until next week which bacteria caused the patient's death.

NDM is not new. Joffe says it is very common in some parts of the world, but hasn't been seen much in Canada and is very rare in Alberta.

He says patients shouldn't worry about becoming ill as a result of the bacteria.

"We do want to assure everyone, particularly patients and families, that the risks from these bacteria's are extremely low," Joffe said.

With files from Susan Amerongen