NDM-1 superbug cases jump to 8 in Canada

Canada now has eight recorded cases of NDM-1 highly drug-resistant superbug infections, up from three cases reported by late August, the Public Health Agency confirms.

Four of the patients came from British Columbia, one from Alberta, two from Ontario and one from Quebec, said Dr. Michael Mulvey, chief of Antimicrobial Resistance and Nosocomial Infections at the federal agency.

Two of the four a 76-year-old B.C. woman and a Quebec patient died, although not directly from the NDM-1 bacterial infections, Mulvey said.

The B.C. woman, whose case is described in the journal Emerging Infectious Diseases, died from complications of sepsis. The Quebec patient, whose sex was not identified, succumbed to cancer.

At least five of the eight people had travelled to India or Pakistan, where NDM-1 superbug infections are becoming more widespread. Four of them had spent time in hospital in those countries, and one person had contact with the health-care system.

NDM-1 is an enzyme recently found in several types of bacteria, including some strains of E. coli. NDM-1 or New Delhi metallo-beta-lactamase makes the microbes resistant to most, if not all, antibiotics.

The 76-year-old woman had returned to Vancouver in February after spending more than three months in northern India. She had developed persistent diarrhea while in that country, where she was hospitalized and treated for high blood pressure, congestive heart failure and ongoing diarrhea.

She was treated with antibiotics for a urinary tract infection without success and was transferred back to Canada, where her condition deteriorated in hospital and she died.

Tests showed the woman had contracted strains of E. coli and Klebsiella pneumoniae, both of which contained NDM-1.

Red flag for doctors, not public

"She was a very ill person," said Mulvey, lead author of the report published Wednesday in the U.S. Centers for Disease Control journal.

Mulvey said the case report is intended as a red flag for the medical community.

"We're highlighting that it's in Canada, that many other countries now are reporting NDM-1 infections," he said from Winnipeg. "Many of them are linked to India, Pakistan, Bangladesh.

"The U.S.A. has seen it [and] numerous countries in Europe, Japan, Hong Kong, Taiwan, Australia.

"I guess these are sort of initial cases. They haven't really spread a great deal in any of these countries. But they're starting to see them sporadically," said Mulvey.

He noted that the superbug infections are on the rise in the U.K. and are becoming more pervasive in south Asian countries like India.

While he said the emergence of NDM-1 bacterial infections should not alarm the public, it is a concern for infectious disease experts because the bugs "just became more difficult to treat."

"And the other concern is that there are essentially no new antibiotics in the pipeline that are being developed right now, so we're a number of years away before we see anything new to combat these infections."

NDM-1 infections are not reportable, meaning doctors aren't required to inform provincial and federal health officials about cases. But a group of 50 hospitals across the country, which make up the Canadian Nosocomial Infection Surveillance program, has been keeping track of cases involving NDM-1-affected organisms since September 2009, he said.