August 11, 2010

New Antibiotic-Resistant Superbug On The Rise

Experts say that a new superbug could spread throughout the globe that is resistant to even the most powerful antibiotics.

Researchers have found a new gene called New Delhi metallo-beta-lactamase, or NDM-1, in patients in South Asia and in Britain.

The new gene makes bacteria highly resistant to most antibiotics, including the most powerful class known as carbapenems.  The experts say there are no new drugs on the horizon that can battle it.

Timothy Walsh, who led the study, said that he feared the new superbug could soon spread around the world.

"At a global level, this is a real concern," Walsh, from Britain's Cardiff University, said in telephone interview with 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."

The overuse and misuse of antibiotics have helped grow drug-resistant "superbug" infections like methicillin-resistant Staphyloccus aureus (MRSA).

Walsh's team found that NDM-1 is becoming more common in Bangladesh, India, and Pakistan and is also being brought back to Britain in patients returning after treatment.

"India also provides cosmetic surgery for other Europeans and Americans, and it is likely NDM-1 will spread worldwide," the scientists wrote in their study.

Antibiotic research has been a "Cinderella" sector of the pharmaceuticals industry for many years.  It shows a mismatch between the scientific difficulty of finding treatments and sales of these types of products are likely to generate because new drugs are typically saved for only the sickest patients.

However, the new threat of superbugs is encouraging a hunt for new types of antibiotics for companies like Pfizer, Merck, AstraZeneca, GlaxoSmithKline and Novartis.

The researchers collected bacteria samples from hospital patients in India, Chennai and Haryana.

They said that they found 44 NDM-1 positive bacteria in Chennai, 26 in Haryana, 37 in Britain, and 73 in other sites in Bangladesh, India and Pakistan.

The scientists wrote in The Lancet Infectious Diseases journal on Wednesday that bacteria derived from the NDM-1 are resistant to many antibiotics like carbapenems, which is a class of drugs often reserved for emergency use and to treat infections caused by other multi-resistant bugs like MRSA and C-Difficile.

Anders Ekblom, global head of medicines development at AstraZeneca, told Reuters he saw "great value" in investing in new antibiotics.

"We've long recognized the growing need for new antibiotics, he said. "Bacteria are continually developing resistance to our arsenal of antibiotics and NDM1 is just the latest example."

Johann Pitout from the University of Calgary in Canada said in reference to Walsh's findings that it was important to be alert to the new bug and start screening early.

"If this emerging public health threat is ignored, sooner or later the medical community could be confronted with carbapenem-resistant (bacteria) that cause common infections, resulting in treatment failures with substantial increases in health-care costs," Pitout wrote in a commentary in same journal.

Dr. David Livermore, a researcher who works with U.K.'s Health Protection Agency (HPA), told BBC news:   "There have been a number of small clusters within the UK, but far and away the greater number of cases appear to be associated with travel and hospital treatment in the Indian subcontinent.

"This type of resistance has become quite widespread there.

"The fear would be that it gets into a strain of bacteria that is very good at being transmitted between patients."


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