Medical tourists pick up antibiotic resistant gene

MRSA infections might be down, but there's another bug that is spreading from India. The NDM-1 gene in bacteria is prevalent in India, but is spreading to other parts of the world through medical tourism.
Written by Boonsri Dickinson, Contributing Editor on

An antibiotic resistant gene has been identified in India and patients who traveled there for medical tourism are picking up the bug too. Does this really hint at a gloomy future for us?

When I read The Guardian article called "Are you ready for a world without antibiotics," I got chills. I keep hearing this concern echoed.

When I was in San Francisco, I spoke with Kevin Judice, the CEO of Achaogen, about his company's mission to discover new ways to treat drug-resistant pathogens. He warned me of these gram-negative resistant bacteria that might launch us into an era without antibiotics. But that's also why his company is focused on developing drugs to combat multi-drug resistant gram negative bacteria and Methicillin-resistant Staphylococcus aureus, or MRSA.

Doctors and the government prepared for the fight against the gram-positive superbug MRSA and the outbreaks appear to be more controlled. Infection of MRSA in the hospital has dropped.

But Darwinian evolution is part of life — and bacteria will continue to evade the drug weapons we throw at it. The bacteria will find some way to survive.

Meet NDM-1 gene. Cardiff University professor Tim Walsh discovered the NDM-1 gene in Klebsiella pneumoniae and Escherichia coli bacteria. It was first identified in a Swedish patient who was infected after undergoing a procedure at an Indian hospital in 2009.

The bug has been found in the UK, US, Australia, and in a number of other countries. Some fear that it will spread throughout the world as medical tourism remains a popular and cheap alternative.

What's worse, the mutation makes bacteria resistant to nearly all antibiotics — even the ones that are supposed to act as our last line of defense.

The Lancet reports the spread of the mutated gene from where it is common in India and Pakistan back to the UK. The researchers report the incidence of the gene mutation as follows:

They identified 44 (1.5%) NDM-1-positive bacteria in Chennai, 26 (8%) in Haryana, 37 in the UK, and 73 in other sites in Bangladesh, India, and Pakistan. NDM-1 was mostly found in E coli (36), the most common cause of community-associated urinary tract infections, and K pneumoniae (111).

The gene can hop from one strain of bacteria to another because it is found on plasmids in the bacterial nuclei. Its location on the plasmid makes the mutant gene pretty promiscuous. While the infection has been found in a small number of people, experts worry that it transfers between different types of bacteria, which makes it harder to contain.

The fact that it exists in gram-negative bacteria, limits the number of drugs in the pipeline that can treat it.

Drug-resistant bacteria like the NDM-1 mutation are typically a problem in hospitals. Not only do the patients have welcoming open wounds, their immune systems are weaker, and the antibiotics they are on kill off healthy bacteria and let the drug-resistant ones flourish.

The growing trend for medical tourism will enable this bug to spread throughout the world. We are seeing what some experts believe, is the tip of the iceberg, in our inability to treat infections.

It only took this mutant three years to rise from obscurity to infect up to 3 percent of the population in India and Pakistan. The gram-negative bacteria resides in the gut and the fact that only two drugs can treat this infection (if at all) has some experts worried about the potential public health risk.

“The rapid emergence of these multi-drug resistant NDM-1 producing bacteria and their potential worldwide spread could herald a period in which antibiotics become redundant and demands very close international monitoring and surveillance," Walsh says in a statement.

The Guardian paints a dark picture of what the world would be like if antibiotics couldn't kill infectious bacteria: Transplant surgery can't be done without running the risk of infection from life-threatening bacteria, routine appendix operation becomes dangerous once again, pneumonia will return as big-time killer, gonorrhea will become resistant, and there's really going to be no way to treat tuberculosis.

The best thing doctors can do is practice better hygiene and take extra precaution in the hospital. Unfortunately the NDM-1 doesn't discriminate. It has been found in the Asian community, spread through contaminated water — and can be spread to other parts of the world through travel.

Like my colleague Andrew Nusca mentions, the Indian government is calling the study unscientific and anti-India.

Related on SmartPlanet:

This post was originally published on Smartplanet.com

Editorial standards