A Down Side of Evolutionary Change: Antibiotic Resistance
In the days before antibiotics were widely available and widely used, people knew the dangers of infection. Even minor injuries like cuts and scrapes were taken far more seriously. Like they say, an ounce of prevention is worth a pound of cure — all the more so when there isn't any cure.
Fast-forward to today. People tend not to view cuts and scrapes as being potentially serious medical conditions. Prevention seems less important because we have a pound of cure — tons, in fact. In 2007, people in the United States used millions of pounds of antibiotics, and therein lies the problem. With each passing year, antibiotics become less effective as bacterial populations evolve to be resistant to them.
Although recent news stories warning people about antibiotic-resistant strains of bacteria may lead you to believe that the phenomenon is relatively recent, it's actually as old as the use of antibiotics. Penicillin, the first widely used antibiotic, dates to the end of World War II. Within four years of its introduction, scientists found penicillin-resistant bacteria, and the incidence of resistance has increased steadily to the present day.
You'd think that having identified that bacteria began to evolve almost immediately in response to penicillin would have encouraged people to be a bit more careful about the use of antibiotics. But we weren't, partly because it's hard to not use a medication that's so effective (many people considered penicillin to be a miracle drug) and partly because, at the time, new antibiotic compounds were being discovered regularly. When one compound was no longer effective, doctors simply switched to a different one. The scenario is very different today.
In recent years, bacteria have been gaining on us: The rate at which researchers have discovered new medically useful antibiotics has slowed, but the steady march of the evolution of resistance continues unchecked. Again, the evolution of resistance isn't new. In every case, scientists have noted the existence of antibiotic-resistant bacteria shortly after the antibiotic is introduced.
Today, we humans now find ourselves facing bacteria that are resistant to many — and, in some cases, all — available antibiotics. Examples include staph, tuberculosis, syphilis, and gonorrhea. The most frightening thing we can observe from this information is that, in the end, all of our antibacterial compounds end up being defeated.