Why is it important to keep looking for different methods of fighting disease?

Answer 1

Some medical techniques are timeless; they worked before, they still work, they'll work forever. But some, like antibiotic medicines, are always under development. Here's why.

When you take an antibiotic, you are conducting a forced evolutionary process within your own body. Let's say that you are ill from an infection of BugA, and that you are taking Drug-B for it. With the first dose, you probably killed half of the BugA germs in your body, and you probably feel better quickly. With the second dose, you've killed half of the remaining BugA organisms, and you feel even better. a third dose, and you've killed half of THOSE, so that you've killed 7/8ths of all the BugA germs.

But you must keep taking the Drug-B pills for it, even though you feel better. Because the first pill killed the half of the BugA bacterial that were the weakest, the most susceptible to the drug. After 3 doses, you've killed 7/8ths of the BugA bacteria - but the survivors are the BugA germs that are the least affected, the most resistant, to that drug. Even if you complete the full 10-day course of the antibiotic, there are still a few surviving BugA germs, and these are the hardiest, most resistant bugs. THOSE are the ones that will survive and go on to make you, or other people, sick again. The Next time the doctor prescribes Drug-A for that infection, it won't work as well - because that case of the disease came from bugs that had already survived this drug before.

And so doctors must continue to develop new antibiotics, because the older ones lose their effectiveness to BugA. And if you failed to take the full course of the antibiotic, you're just making things worse for everybody, because more of the hardy and survivable germs will go on to make other people sick.