| |
|
 |
||
 |
 |
|||
| |
||||
 |
 |
|||
 |
 |
|||
The Immune Wars are being waged in hospitals throughout the world. New antibiotics are cultured, tested, rushed through FDA approval and sent to the front at an unprecedented rate. The frightening thing is, despite our legions of biochemists hard at work, humans are losing the war. Staphylococcus aureus, or "staph" infections have been troublesome since the earliest days of surgery. The infection sets in within the incision the surgeons make to do their job. With the body recovering from the surgery, the staph infection spreads easily, taking advantage of the preoccupied immune system and can kill the patient. Then came penicillin. Penicillin, the wonder drug, was 100% effective in treatment of staph infections (among other bacterial fiends) upon is introduction (Palumbi). By the late 60s, however nearly every hospital in the world switched from penicillin to methicillin, a new (at the time) antibiotic, because 99% of the known strains of Staphylococcus aureus had developed major resistance to penicillin. This is evolution at its worst (or best, if you happen to be a bacterium). Over time, staph was exposed to penicillin long enough that the pressure was on for evolution to "build a better mouse," so to speak. And a better mouse indeed, since penicillin is now nearly 100% ineffective in treating staph infections (Palumbi). By the mid 90s, only vancomycin, the atomic bomb of antibiotics, was able to reliably treat staph infections. In 2000, Zyvex and Synereid were developed, call these the fusion bombs of antibiotics, to modify and augment vancomycin to treat staph infections that were building a resistance even to it. Only one bacterium, Entrococcus, has developed high level resistance to vancomycin but scientists have shown that by moving vancomycin-resistant genes from Entrococcus to Staphylococcus aureus that staph then evolves the same level of resistance (Palumbi). Obviously, this is the greatest example of extremely rapid evolutionary change -- at the hands of humans, no less. Staphylococcus would never have evolved in the manner it has without humans' dabbling in antibiotics. The question that remains is: can human ingenuity out run evolution? (On a side note, many scientists are directing their research more toward the genetics of bacteria such as staph in the hopes of discovering a way to shut off certain genes within the bacteria. Genes make bacteria act the way they do, an organism cannot evolve to counteract genetic changes. It's like trying to darken a room. Antibiotics hold sheets up in front of the lights, genetic research attempts to turn the lights off.) |