Are the Micro-Bugs Winning?

Bacteria are everywhere. Those tiny, simple little creatures create rich organic soil, munch through compost, clean oil slicks, manufacture the oxygen we breathe, and "fix" atmospheric nitrogen that plants need. They've been found living in boiling hot springs, arctic ice, the middle of rock chunks, and nuclear reactors. When Apollo 12 astronauts retrieved a camera left on the moon for almost three years, they found Streptococcus bacteria that had stowed away on earth, then quietly set up housekeeping on the camera lens assembly.

Closer to home, bacteria help digest our food, synthesize vitamins, and happily munch away at our dead outer layer of skin. They even act as scouts for more sinister kinds of bacteria. Count them all up, and they outnumber our own body cells by perhaps a hundred to one. Zooming out again, it's estimated that all the bacteria on earth piled up on the continents would top out at five feet thick.

Usually, when we think about bacteria, we're most likely thinking about the one species in a thousand that makes us sick with strep throat, pneumonia, tuberculosis, some kinds of food poisoning or ear infections, even some ulcers. When we're afflicted with one of these strains, a visit to the doctor and a course of antibiotics usually clears it up. It's easy to forget that antibiotics have been available for only the last fifty years, and their availability has saved countless lives of people who would otherwise have died, were it not for a few pills over a few days.

Bacteria reproduce by dividing neatly into two identical copies of the parent, and compared to the life we see every day, they do it incredibly quickly. If conditions are right, some bacteria can double themselves every 20 minutes. Bacteria are also promiscuous. They swap genes - the little instruction manuals that build and run every cell - back and forth like we swap good books, and they don't necessarily care if they swap with the same species or not. Therein lies the problem.

Because bacteria reproduce so quickly, and because they share genes, infectious bacteria (called pathogens) can evolve antibiotic resistance very rapidly - within just a few months in some cases. Antibiotics work either by interfering in the pathogen's ability to reproduce, or by killing the pathogen outright. Just like Roundup on weeds, antibiotics kill most, but not always all, bacteria. Perhaps a bacterium has made a beneficial mistake copying itself (called a mutation), or it swapped a gene with another bacterium that allows it to escape the antibiotic effects. The few that escape antibiotics are then resistant. When a pathogen develops resistance, remember it's going to make many identical copies of itself. Each of those copies will also be resistant to one or more antibiotics. That means the pathogens can no longer be treated by some, or all, of the antibiotics available. Our rapid travel also helps resistant pathogens gain a foothold much faster. If I "catch" resistant tuberculosis from the guy on the plane next to me, then not only do I have a hard time getting rid of it, but I can share it with everyone I contact.

First, avoid what's called prophylactic, or preventive, use of antibiotics. Colds and the flu are caused by viruses, not bacteria, so insisting that your doctor prescribe antibiotics not only won't help but could hurt. The AMA and FDA have undertaken a campaign to educate doctors about this. Prophylactic prescription of antibiotics is still a big problem in pediatrics, according to the American Academy of Pediatrics. It's easy to understand why; no one wants to see children sick and miserable. Parents often insist on antibiotics, even when the infection isn't bacterial. Don't ask your pediatrician or doctor for antibiotics if you're not sick with a bacterial pathogen, and don't accept them if offered. If you do have a bacterial infection and you're prescribed antibiotics, take your doctor seriously when she tells you to finish the entire course of treatment, even if you feel perfectly fine.

If you don't, you risk creating the conditions for evolution of a drug-resistant strain that could affect others. Check the AMA or AAP web sites (www.ama-assn.org and www.aap.org) for more information.

Next, cut down or eliminate, where possible, those antibacterial cleaners in your household. A quick trip to the local mass grocer or variety store shows how hard this can really be. Just about every commercial cleaning product out there proclaims, "Antibacterial!" Used indiscriminately, that's just another way of saying, "causes resistance by inducing rapid evolution!"

The next one might take some getting used to: let your kids get dirty. Exposure to low levels of both benign bacteria and pathogens may help them fight off a resistant pathogen down the road. During European smallpox outbreaks in the 18th and 19th centuries, milkmaids largely escaped infection because their daily, low-level exposure to the closely related cowpox allowed them to develop immunity to deadly smallpox. The Journal of the American Medical Association and the British medical journal, The Lancet have both reported studies suggesting that kids who grow up on farms, exposed to dirt and animals, are generally healthier than their city counterparts - even when controlling for denser populations in cities, where disease transmission is more likely.

Choose dairy and meat products that have been raised without antibiotics whenever possible. (Yet another check in the "benefits of a co-op" column!) Prophylactic antibiotics are almost ubiquitous in conventional agriculture, for two reasons. First, conventional animals are raised in dense populations, facilitating the spread of pathogens. Even if those animal pathogens don't affect humans in the end, remember that bacteria can swap genes with pathogens that do affect humans. For instance, a 1998 article in Science suggested that the high rate of drug-resistant ear infections in kids might have come from a gene swap between the pathogen that causes ear infections and the benign E. coli that lives in our digestive systems. Second, beef cattle and hogs get antibiotics in especially high, steady doses because the grain we feed them to fatten them up and give our meat that nice marbling, is hard on their systems. They can't digest it well. As a result of the grain feeding, the benign E. coli in their digestive systems adapt to the highly acidic conditions, attacking the linings of the stomach and rumen and potentially sickening the animal without antibiotic use. When you hear about E. coli contamination in ground beef, it's that "super-bug," not the mild strain that we, and grass-fed animals, normally carry around. Salmonella appears to occur less frequently in truly free - ranging poultry and their eggs.

Be cautious about alternative healing solutions too. There's no doubt that "alternative medicine" has a lot to teach conventional Western medicine. In the end, anything that selectively attacks some bacteria and not others, has the potential to induce evolution of a drug-resistant strain. The bacteria don't care how it happens; their only mission is to survive and reproduce. Responsible naturopaths and herbalists can tell you how a supplement or an herb works, but because alternative medicine has been scoffed at for so long, there are few double-blind studies (the gold standard in science) about their effects on pathogens. Finally, if you visit someone in the hospital, or you're there yourself, wash your hands often. Observe health care workers and request they do the same before examining you or a loved one. (Most are fastidious about this now; hospitals are taking antibiotic resistance pretty seriously since that's usually where such cases are noted first.) If you have a wound, watch it carefully and tell someone immediately if you notice any yellowish or greenish discharge, swelling, or redness. Don't wait; this is one time where "Minnesota Nice," isn't!