New superbug gene may spread worldwide: study
Published Wednesday, August 11, 2010 10:25PM EDT
Researchers in England are warning of a new gene that can turn any bacteria into a superbug, rendering it impervious to most antibiotics. They also say the gene may soon begin rapidly spreading worldwide.
The gene was first discovered in hospitals in India and Pakistan, but cases have also been reported in Australia, the Netherlands, the United States -- and Canada.
The new gene, called NDM-1, appears to be most commonly linked to the bacteria that cause urinary tract infections and some types of pneumonia. However, it can also impact other types of bacteria.
"It's not a single bug. It's not like MRSA, for instance," lead researcher Timothy Walsh, of Cardiff University in the U.K., told CTV News Channel on Wednesday.
MRSA refers to a drug-resistant strain of bacteria.
"It's a type of resistance that's carried on a mobile piece of DNA called a plasmid, and it's able very quickly to transfer from bacteria to bacteria," said Walsh.
He said the gene renders infections immune to all but two antibiotics.
Writing in the journal Lancet Infectious Diseases, the researchers say the gene is already widespread in India. The gene has also been identified in 37 British patients, all of whom travelled to India or Pakistan for low-cost surgery.
The researchers say that with the growing popularity of medical tourism, where patients seek a cheap operation or hope to jump a long surgical queue back home, potentially dangerous superbugs may begin popping up around the globe.
"The potential of NDM-1 to be a worldwide public health problem is great, and co-ordinated international surveillance is needed," the authors wrote.
In a commentary piece published with the study, microbiologist Johann Pitout of the University of Calgary, called for worldwide monitoring for the gene, especially in countries that are popular with medical tourists.
"The spread of these multi-resistant bacteria merits very close monitoring," Pitout wrote.
"The consequences will be serious if family doctors have to treat infections caused by these multi-resistant bacteria on a daily basis."
Infectious disease specialist Dr. Neil Rau said the gene is not widespread in Canada, and cautioned that these so-called superbugs may not lead to debilitating disease.
"This word superbug is a bit of a dangerous moniker, it can be a rather frightening word for people," Rau told News Channel. "It's a superbug in the sense that it's resistant to antibiotics, but it may not be more virulent and able to attack and cause infection than the standard strains."
Rau said researchers have yet to determine the "survival advantage," or fitness, of the gene to continue to churn out these superbugs.
But he said should the gene continue circulating, it will likely have a greater impact in a hospital setting where "the standard antibiotic cocktails that we use today may not be effective three or five years from now. So the whole treatment paradigm or approach might be changed."
Walsh said researchers are already setting up a network of observers in India to get a closer look at whether the gene is prevalent in the community.
But he said so far, the general public in North America is "not vulnerable at all" unless they are travelling to India or Pakistan.
"I would suggest that if people are travelling to India or Pakistan they drink bottled water, they be careful of what they eat and where they eat, and just wash your hands frequently," Walsh said.
With files from The Associated Press