MEDICINE: The Killers All Around

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Unfortunately, as Columbia University's Dr. Harold Neu observed in the journal Science, "bacteria are cleverer than men." Just as they have adapted to nearly every environmental niche on the planet, they have now begun adjusting to a world laced with antibiotics. It didn't take long. Just a year or two after penicillin went into widespread use, the first resistant strain of staph appeared. As other antibiotics came along, microbes found ways to resist them as well, through changes in genetic makeup. In some cases, for example, the bacteria gained the ability to manufacture an enzyme that destroys the antibiotic.

By now nearly every disease organism known to medicine has become resistant to at least one antibiotic, and several are immune to more than one. One of the most alarming things about the cholera epidemic that has killed as many as 50,000 people in Rwandan refugee camps is that it involves a strain of bacterium that can't be treated with standard antibiotics. Relief agencies had to scramble for the right medicines, which gave the disease a head start in its lethal rampage.

Tuberculosis, too, has learned how to outwit the doctors. TB is an unusually tough microbe, so the standard therapy calls for several antibiotics, given together over six months. The length and complexity of the treatment have kept underdeveloped nations from making much progress against even ordinary TB. But now several strains have emerged in the U.S. and other developed countries that can't be treated with common antibiotics.

Even such seemingly prosaic but once deadly infections as staph and strep have become much harder to treat as they've acquired resistance to many standard antibiotics. Both microbes are commonly transmitted from patient to patient in the cleanest of hospitals, and they are usually cured routinely. But one strain of hospital-dwelling staph can now be treated with only a single antibiotic -- and public health officials have no doubt that the germ will soon become impervious to that one too. Hospitals could become very dangerous places to go -- and even more so if strep also develops universal resistance.

One of medicine's worst nightmares is the development of a drug-resistant strain of severe invasive strep A, the infamous flesh-eating bacteria. What appears to make this variant of strep such a quick and vicious killer is that the bacterium itself is infected with a virus, which spurs the germ to produce especially powerful toxins. (It was severe, invasive strep A that killed Muppeteer Jim Henson in 1990.) If strep A is on the rise, as some believe, it will be dosed with antibiotics, and may well become resistant to some or all of the drugs.