why antibiotics are effective against bacteria but not viruses.?
359112
You first have to realize that anitbiotics usually work by targeting some necessary life process that goes on within a cell. It could protein production (aka Translation), it could target gene expression (aka Transcription) or other processes like membrane and cell wall production. These are by far the most common targets for antibiotics (with protein production and cell wall production making up the biggest bulk of the targets.)\n\nAs far as viruses go, you have to realize that viruses don't do these things on their own. So you can't target something that doesn't exist in the agent you want to fight off.\n\nYou see viruses are obligate intracellular pathogens. Which means that have to invade a living cell in order to reproduce. Because viruses don't have the machinery to make their own proteins or transcribe their own genes they have to hijack the machinery of the cell they infect to do it for them.\n\nThis should make it easy to understand why we can't developer antiviral medications that work the same way antibiotics work to help rid our bodies of viral infections. If we develop a drug that stops viral protein production, because it is using the same machinery we normally use, we would in effect be killing all our cells, not just the ones that have viruses in them. These types of drugs would be way to toxic to our healthy cells.\n\nYou might ask yourself, well then why do antibiotics work on bacteria if they are targeting processes inside of bacteria that we need to do also (ie. protein production or cell membrane production)? The answer to that is evolution. Enough evolutionary time has passed that the processes we use to do these things aren't similar enough to cause cross reactivity. As time passes, things change. That's the basis for evolution. The longer two organisms have time to diverge from one another the more able researchers are able to use those differences to treat if one chooses to.\n\nIn the case of bacteria. We can take advantage of the differences between them and us to get rid of them if they infect us.
210836
There are only a handful becasue more antibiotics attack prokaryotic cellular structures, such as the prokaryotic ribosome, but protozoa are eukaryotic. Examples that are used inlcudeamphotericin B, metronidazole, pentamidine and tinidazole
736874
To treat it, not really. Antibiotics are needed.\n\nThere MAY be something to give temporary relief of symptoms, but they wouldn't affect the bacterial.
121470
Your question may not be phrased correctly.  Antiobiotics are on the rise because they work and we get sick.  They are also added to animal feed to keep them healthy so we can eat them.\n\nI would think that the question you should be asking is, "Why is antiobiotic resistance on the rise today".  The answer is that our prolific use of antibiotics, even when we don't need them, has weeded out the bacteria that were most susceptible while allowing those with mild resistance to survive better from reduced competition.  Over time asthese mildly resistent bacteria are spread and further selected for my antibiotics they lead to moderate resisteance to high resistance and ultimately to complete resistance.  This doesn't make the disease worse, but they are harder to eliminate which can make the disease progress and become worse.
17905
viruses cause viral infections, and bacteria cause bacterial infections. But they're also different in other ways.\n\nViruses are much smaller than bacteria.\n\nViruses are not living organism so they need a host.
1070753
I'm not sure about infection, but antibiotics can do it.
865599
Viral illnesses CANNOT  be treated with antibiotics.  Usually viruses need to just run their course and just treat the symptoms, although there are few viruses that do have anti-viral meds. Bacterial illnesses CAN be treated quite effectively with antibiotics.
490824
hi my name is Geeth Prajwal from India i hope this will help you\n\n\n\nIn order to be useful in treating human infections, antibiotics must selectively target bacteria for eradication and not the cells of its human host. Indeed, modern antibiotics act either on processes that are unique to bacteria--such as the synthesis of cell walls or folic acid--or on bacterium-specific targets within processes that are common to both bacterium and human cells, including protein or DNA replication. Following are some examples. \n\nMost bacteria produce a cell wall that is composed partly of a macromolecule called peptidoglycan, itself made up of amino sugars and short peptides. Human cells do not make or need peptidoglycan. Penicillin, one of the first antibiotics to be used widely, prevents the final cross-linking step, or transpeptidation, in assembly of this macromolecule. The result is a very fragile cell wall that bursts, killing the bacterium. No harm comes to the human host because penicillin does not inhibit any biochemical process that goes on within us. \n\nBacteria can also be selectively eradicated by targeting their metabolic pathways. Sulfonamides, such as sulfamethoxazole, are similar in structure to para-aminobenzoic acid, a compound critical for synthesis of folic acid. All cells require folic acid and it can diffuse easily into human cells. But the vitamin cannot enter bacterial cells and thus bacteria must make their own. The sulfa drugs such as sulfonamides inhibit a critical enzyme--dihydropteroate synthase--in this process. Once the process is stopped, the bacteria can no longer grow. \n\nAnother kind of antibiotic--tetracycline--also inhibits bacterial growth by stopping protein synthesis. Both bacteria and humans carry out protein synthesis on structures called ribosomes. Tetracycline can cross the membranes of bacteria and accumulate in high concentrations in the cytoplasm. Tetracycline then binds to a single site on the ribosome--the 30S (smaller) ribosomal subunit--and blocks a key RNA interaction, which shuts off the lengthening protein chain. In human cells, however, tetracycline does not accumulate in sufficient concentrations to stop protein synthesis. \n\nSimilarly, DNA replication must occur in both bacteria and human cells. The process is sufficiently different in each that antibiotics such as ciprofloxacin--a fluoroquinolone notable for its activity against the anthrax bacillus--can specifically target an enzyme called DNA gyrase in bacteria. This enzyme relaxes tightly wound chromosomal DNA, thereby allowing DNA replication to proceed. But this antibiotic does not affect the DNA gyrases of humans and thus, again, bacteria die while the host remains unharmed. \n\nMany other compounds can kill both bacterial and human cells. It is the selective action of antibiotics against bacteria that make them useful in the treatment of infections while at the same time allowing the host to live another day.
73638
There are a conbination of things that are creating these different strains of germs. Darwin's theory of evolution is a good explanation of one reason for the "stronger" germs. Antibiotics and antibacterial"stuff" eliminates the common types of bacteria. The ones that resist are what remain and through mutation new types of bacteria are left. A lot of times these newer bacteria seem "stronger" because they are immune to our antibiotics. Our bodies are also not accustomed to these newer strains of bacteria. \n\nIt's not neccesarily a "stronger" bacteria, it's a different strain that has become immune to the antibiotics that are overused.
418861
There are quite a few, you must ask your doctor to be sure that the right antibiotic is treating the right infection-bacteria.  I do know that prolong use of any antibiotic will build up your immune system to the antibiotic and it will not be effective to fight off future infections.
338772
Bacteria are tiny microorganisms that have a cell wall, a ring of DNA, and some ribosomes.\n\nViruses are extremely small packets of DNA wrapped in a protein coat. They don't contain much more than that and can't survive nor replicate on their own.\n\nBacterial STDs are caused by bacteria. Bacteria can be killed with antibiotics.\n\nViral STDs are caused by viruses. Viruses cannot be killed with antibiotics, but many viral illnesses can be prevented with vaccines.\n\nBacterial STDs include: gonorrhea, chlamydia, syphilis\nViral STDs include: HIV, herpes, genital warts, hepatitis B
848383
Not as of yet, the problem is that it has been mutating to quickly for an effective vaccine to be developed.  It is a virus, so it can't be killed with antibiotics.  It has to be prevented with vaccination and since it has shown a high mutation capacity it may be some time before anything is discovered to inhibit its mutation capabilities and then kill it.
512652
There are several viruses that infect insects, my favorite being Cricket paralysis virus because I have no idea how anybody could write a grant proposal for looking into the molecular basis for crickets that don't move...anyhow, most antibacterial and antifungal drugs used on humans should work every bit as well on insects, so I guess we could probably treat them for many infections...
1176734
No need to worry.  There is no decreased protection during use of antibiotics.
29525
Antibiotics are used to combat bacterial base illnesses it is viral one the antibiotics do not work with. \nDoctor will sometimes prescribe pill for patients for a placebo effect meaning that if the patient think the pill will work then it will. \nI doubt profit has anything to do with it because a doctor makes the same whether they prescribe anything or not.
4271
Antibiotics are a valuable tool for fighting bacterial infections which persistantly do not resolve with your body's own Immune System.\n\nAntibacterial products have been touted to reduce infection from exposure to things you touch, wear, etc.  This is valuable for some people with compromised immune systems, but the normal healthy person really has no need for such products.\n\nIn fact, the use of those products and antibiotics are creating stronger more resistant bacteria in our environment.  With stronger more resistant bacteria comes the risk of NOT being able to get rid of an infection when one occurs.  \n\nExamples of resistant bacteria are MRSA and VRE.  These are very difficult infections to fight BECAUSE of their resistance.\n\nSo, to recap, most of the time exposure to bacteria will actually increase your immune systems ability to FIGHT that bacteria later and using too many products to kill bacteria can actually, in the end, hurt us.
615537
Penicillin is most effective against Gram positive bacteria, so any diseases caused by these bacteria may be treated with penicillin.  Some examples include strep throat, staph infections, and food poisoning caused by Listeria.