When you think of a so-called "superbug" you probably think of what’s known as MRSA (methicillin-resistant staph aureus), a bacteria resistant to many antibiotics that has been found in hospitals for decades and more recently has even appeared in gyms. But this bacteria is generally treatable, and the hype surrounding it has been greater than the risk posed to patients.

But now a new superbug is emerging that is more worrisome. A garden variety bacteria that invades the intestine, causing diarrhea, or the bladder, causing a urinary tract infection, has now acquired a gene (NDM-1) that renders it resistant to almost all antibiotics.

This bacteria has spread in India and is now jumping to other countries (including the U.S.) when people travel to India for medical tourism.

Here are a few points to keep in mind:

1. Bacteria grow in millions of colonies, and in order to survive they seek to gain resistance to the drugs that kill them.

2. India is an overpopulated country that overuses antibiotics, which increases the chance of resistance developing in patients.

3. Drug companies are not making new antibiotics to fight these bacteria, because it isn't profitable enough for them.

4. Hospitals and clinics are helping to spread these bacteria, by not using proper hygiene and disinfection techniques.

5. Even though I am concerned about this emerging bacteria, the chances that you or anyone in your family will get it are still extremely low, even if you travel to India.

At this point, the new strain of resistant bacteria remains quite scarce here, with only 3 cases in the U.S. so far, all among travellers to India who were exposed to it in medical facilities there. 

It is impossible to tell whether it will take hold and become widespread like MRSA or remain as isolated cases. There are other bacteria, more native to the U.S., including KPC-producing bacteria (Klebsiella Pneumoniae Carbapenemases) which are also highly resistant due to a genetic change. KPC is much more prevalent here and is deadly 40 percent of the time.

Marc Siegel M.D. is an associate professor of medicine at NYU Langone Medical Center and a Fox News Medical contributor.

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