Why antibiotics don't work against viruses? Answer for?
Answers
This one is actually pretty simple. Let's look at two of the common ways antibiotics work. (Others exist, but the principles are similar)
1- inhibit the synthesis of the cell wall. Most (not quite all) bacteria have cell walls. The antibiotic prevents them from making it, and water comes into the cell by osmosis it pops (Lyse) because the cell wall isn't there to hold it in. (Yes you can get bacteria to live in that antibiotic without a cell wall if you balance the osmosis in a lab, but this doesn't apply to infections). These drugs are usually not too toxic to us (some exceptions), because we don't have cell walls anyway. The point is that viruses simply do not have cell walls. Therefore they are not affected by let's say penicillin and similar drugs.
2- several antibiotics affect the bacterias' ribosome.(sometimes called 70s)this inhibits protein synthesis. We survive because our cells' ribosomes (80s) are not badly affected by these drugs. Our mitochondria do have 70s ribosomes, but we can tolerate the effect better than bacteria do. (Erythromycin, tetracycline, streptomycin are examples). Viruses simply use our ribosomes to make their proteins, so they are not affected any more than we are.
3- a drug that is related to antibiotics (technically not one) is sulfa drugs. They work by inhibiting folic acid synthesis. We don't mind because we eat it instead of making it anyway. Viruses don't make it, so they don't care either. (Anthropomorphizing, I know)
Luckily there are ways to stop viruses
1- vaccines. Many, if not most viruses (HIV is a notable exception) are fairly easy to vaccinate against. You show the body a weakened or dead version (or simply a piece in some cases), and the body makes antibodies and other defenses against them. This typically prevents infection it makes it much milder. Our immune system is good against most viruses, especially if forewarned.
2- viruses do typically rely upon specific enzymes they have that we do not use(so cannot provide for them). You can treat some viruses by interfering with one of these enzymes. We survive because we don't have that enzyme. The downside is that each individual virus species (disease) often needs its own specific drug. Some cases, like herpes and shingles related viruses are affected by the same drug. A few antivirals (antibiotics for viruses) work on several types.
Virus have different biological pathways. They live an feed on the host which are our body cells so when antibiotics enter our body they are unable toattack our body cell so the virus cells are not harmed by them