Should We Be Afraid of the Superbug?
A mysterious infection-breeding gene is sweeping the world -- or possibly just cable news.
For a few days this August, much of the news media in the West became convinced that we were headed back to the 1800s, medically speaking. A study in the September 2010 issue of British medical journal the Lancet argued that bacteria carrying genes for NDM-1, a gene that imparts resistance to a key family of antibiotics, had made their way through India and Pakistan into Britain and were now threatening to derail medical treatment across the developed world. Linked with the always shady-sounding concept of "medical tourism" — the practice of traveling to other countries for budget surgery — the so-called "superbug," able to breed vicious and deadly infections, became an instant media panic during a slow news month. The Drudge Report and Andrew Breitbart’s news website both featured it. A Guardian science columnist wrote, "Now, the post-antibiotic apocalypse is in sight."
Er, not so much. As with most August stories, the reality of superbugs is a bit more complex than the media has portrayed it. Yes, antibiotic-resistant bacteria are a threat, as this week’s news of an outbreak among premature infants in London reminds us. But no one yet knows how bad NDM-1-related infections could be. Not only is it far too early to say we’re headed for apocalypse, we’ve also got a lot to learn from superbugs — namely, how our own over-use of antibiotics is making it more likely that a superbug of the future could live up to this summer’s hype.
Alexander Fleming discovered the first antibiotic by accident in 1928, when he left out a bacterial culture for a month while on vacation and came back to find that some of the bacteria had been killed by a fungus named Penicillium. By the early 1940s, a commercial product, penicillin, was mass-produced to cure bacterial infections in humans, and medical practice hasn’t been the same since.
These days, antibiotics are a major weapon in medicine’s war on disease, used to treat everything from life-threatening infections like meningitis to more run-of-the-mill ear infections. For more advanced medical technologies, like chemotherapy or organ transplantation, antibiotics are needed to prevent and treat infections while patients heal. Neither treatment would be possible without antibiotics.
At this point, in fact, antibiotics are suffering from their own success. They are so engrained in the medical and social culture that over-prescription is a major problem. Recent surveys have found that 70 to 80 percent of doctors’ visits for sinus infections result in an antibiotic prescription. But most sinus infections are caused by viruses, and antibiotics don’t cure viral infections.
The medical sin of antibiotic overuse goes beyond mere ineffectiveness — it actually can be harmful. Here’s how it works: Bacteria are everywhere on our bodies, even when we are not sick. When we take antibiotics for a bacterial infection, they only kill certain bacteria (usually the ones making us sick). Then, as the body gets better, the surviving bacteria multiply and take over. Now and then a few remaining bacteria carry special resistance to antibiotics — which is what kept them alive in the first place. With the other bacteria out of the way, the resistant bacteria (i.e., the superbug) can multiply and sometimes cause problems. For example, if one of those superbugs causes an infection, some antibiotics won’t work anymore, and then you have an infection that is more difficult to treat.
One of the prototypical superbugs caused by antibiotic use (and overuse) is Methicillin-Resistant Staphylococcus aureus (MRSA). MRSA is resistant to many antibiotics, including penicillin, and causes a variety of problems in humans: mostly skin infections, but also more invasive diseases like pneumonia and bloodstream infections.
Another superbug that’s been around for a while but has also taken a recent media tour is Clostridium difficile (C. diff), which can be spread when antibiotics wipe out normal intestinal bacteria that keep C. diff in check. A recent study found C. diff infection occurred in 13 out of every 1,000 hospitalizations. C. diff causes diarrhea, and in some cases a particularly severe and sometimes lethal infection of the colon.
Looking at bacteria carrying the NDM-1 gene, C. diff, and MRSA, it’s not surprising that people would panic over the possibility of these or other, even more resistant, bugs of the future making our advances in antibiotics worthless. And it’s a legitimate fear. Although there are antibiotics and other treatments that work against all known superbugs, bacteria will continue to evolve, developing stronger antibiotic resistance in the future. It is conceivable that bacteria will someday outsmart our best medical technologies.
But it is unlikely that it will happen any time soon. One reason is that there are many different classes of antibiotics, so while some don’t work against superbugs, there are usually others that do. Antibiotics that have been shelved for years might even be re-introduced to fight superbugs, though obviously this would be less than ideal because of higher risk of side effects. A better and more likely solution is for drug companies and other scientists to discover new classes of antibiotics. The financial incentives for heading off a true superbug-led medical catastrophe would be huge — something that always drives medical innovation quite nicely, as it did with treatments for HIV in the 1990s.
Beyond praying for technology to catch up with biology, however, we also need to cut back on the over-prescription of antibiotics, ideally by giving doctors incentives to adhere to standard treatment guidelines. The National Quality Forum has recently endorsed a measure requiring physicians to stop prophylactic antibiotics used during surgery within 24 hours of the end of the procedure, ensuring that people stop getting antibiotics when they stop needing them.
These sorts of measures need to happen everywhere, not just in the United States or in the developed world. Reducing the spread of superbugs in only one part of the world is likely to be ineffective because the ease of global travel and medical tourism can spread superbugs bred in Bangladesh directly to Boston in a matter of hours. So creating stricter standards for antibiotic use in the many countries where patients can bypass doctors and buy antibiotics over the counter from pharmacies would be crucial.
Like the MRSA panic of last summer, this year’s superbug frenzy, too, will die down. On the scale of media-freak-out irrationality, superbugs have more credibility than the Large Hadron Collider apocalypse, for example, but they’re not even up there with swine flu.
Ultimately, as with most such overreactions, the real solution is to give some c
alm thought to the serious problems behind the panic — in this case, over-prescription of antibiotics — and then just be glad it’s September.