DEAR DOCTOR K: I’ve been hearing a lot about “antibiotic resistance.” What does it mean?
DEAR READER: When penicillin was discovered, many people (including doctors) thought bacterial infections would become a thing of the past. Unfortunately, penicillin and other early antibiotics didn’t successfully treat all kinds of bacteria that make us sick.
Even worse, bacteria adapted to fight antibiotics. All they had to do was the thing they do best: Keep multiplying. Bacteria multiply so fast that one bacterium becomes millions in 24 hours. When bacteria (and other cells) divide, mutations (changes in their genes) can occur.
Sometimes these mutations allow the bacteria to resist antibiotics. And when they divide, they pass that antibiotic resistance on to their offspring. Now there are millions of antibiotic-resistant bacteria.
Let’s say that you get strep throat and your doctor prescribes penicillin. Strep throat is a sore throat caused by the bacteria called streptococci. The antibiotic (penicillin) will kill off most of the strep bacteria, but a few strep bacteria might develop resistance to penicillin, survive and multiply. They often remain alive in your throat.
At first, there are not enough of them to cause trouble. But down the road they can cause another case of strep throat.
This time, you might not respond to penicillin. Antibiotic resistance is a serious problem, causing millions of illnesses and more than 20,000 deaths in the United States each year.
Over time, if antibiotic use doesn't change, antibiotics will become less able to treat common infections. We may be left with no drugs in our arsenal that can kill certain bacteria.
Overuse of antibiotics is the most common cause of drug-resistant bacteria. Many people demand antibiotics to treat viral infections. But antibiotics treat only bacterial infections.