Posted on August 12, 2010

Doctors Brace for More Cases As Indian Superbug Hits Canada

Jill Mahoney, Globe and Mail (Toronto), August 11, 2010

At least two Canadians have become infected with a dangerous new superbug from India that is spreading around the world, partly due to medical tourism.

The superbug, which is resistant to almost all antibiotics, has Canadian public-health experts bracing for outbreaks.

“There will be others. It’s just a matter of time,” said Dylan Pillai, a medical microbiologist at the Ontario Agency for Health Protection and Promotion. “It’s just the nature of the beast.”

Researchers reported dozens of cases of British, Indian and Pakistani patients who contracted infections caused by bacteria harbouring an enzyme called New Delhi metallo-beta-lactamase, or NDM-1, in the journal The Lancet Infectious Diseases on Wednesday.

Of 29 Britons, more than half had recently travelled to India or Pakistan and 14 had been admitted to hospitals in the subcontinent, where the drug-resistant enzyme originated, including for kidney transplants and cosmetic surgery.

Two cases have been confirmed among Canadians who spent time in India. In addition, the drug-resistant infection has been found in patients from the United States, Sweden, the Netherlands and Australia.

The Lancet researchers called the superbug’s spread a “clear and frightening” potential “major global health problem,” noting that pharmaceutical companies are not producing new antibiotics for NDM-1 sufferers.

“At a global level, this is a real concern,” lead author Timothy Walsh, a professor of medical microbiology and antimicrobial resistance at Cardiff University in Wales, told Reuters.

“Because of medical tourism and international travel in general, resistance to these types of bacteria has the potential to spread around the world very, very quickly. And there is nothing in the [drug development] pipeline to tackle it.”

With only a couple of effective antibiotics, NDM-1 is one of the most difficult superbugs to treat. There are many more medications available for other drug-resistant infections, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE).

“It’s quite concerning because there are very limited treatment options,” Dr. Pillai said. “We’re really in a tight spot here.”

In a commentary accompanying The Lancet study, Johann Pitout, a University of Calgary professor of pathology and laboratory medicine, urged screening patients who undergo medical procedures in India before they receive treatment in their home countries.

“The consequences will be serious if family doctors have to treat infections caused by these multiresistant bacteria on a daily basis,” he wrote.

In an interview, Dr. Pitout said that his lab analyzed a sample earlier this year from an Albertan who contracted NDM-1 after being hospitalized in India. The patient has recovered.

At the time, Dr. Pitout, a medical microbiologist, was unaware of the new superbug. He said he “put two and two together” after reading medical reports out of Britain, where NDM-1 was first detected in 2008. He plans to publish a paper on the case.

As well, a Vancouver woman contracted NDM-1 in India, where she was hospitalized and treated without success, said Howard Njoo, director-general of the Public Health Agency of Canada’s Centre for Communicable Diseases and Infection Control. In February, the woman came to Vancouver, where doctors found an effective combination of antibiotics, he said.

“This case was, in a sense, not unusual because of the association and travel to India. It still underscores the fact that we haven’t had a case of this bug actually circulating in Canada,” he said.

Dr. Njoo said he was not aware of the details of the Alberta case.

NDM-1 is an enzyme that is produced by bacteria that renders most antibiotics inactive. It is commonly harboured in E. coli and Klebsiella pneumoniae. People infected with NDM-1-producing bacteria often contract urinary-tract infections, pneumonia or blood infections.

“If you get it in the hospital, this could be certainly a tipping point, and if the doctors don’t have good antibiotics to resort to, it could be very, very dangerous,” Dr. Pillai said.

The spread of NDM-1 within health-care facilities can be curbed through strict infection-control measures, including patient isolation and hand washing.

[Editor’s Note: The initial story on the “superbug” can be read here.]