-
Asked by DJNezz to Ceri, Marikka, Matt, Rob, Sally on 7 Nov 2014.
-
Sally Cutler answered on 7 Nov 2014:
What a great question! Generally the answer is no. This causes a real problem because if you take antibiotics you can upset or kill the good bacteria that help to protect us as well as the ones that were making you ill. Sometimes another infection can follow as your good bacteria have been damaged. Antibiotics have different ranges of activity with some just killing a few types of bacteria whilst others are more like “domestos” killing many types. It is the last group that can damage both good and bad bacteria, so should be used with care.
-
-
Robert Hampson answered on 7 Nov 2014:
There are many different kinds of germs that can infect a person (e.g. bacteria, viruses, fungi, parasites,…). When designing drugs to treat these infections, scientists need to find a biological system that is important to the infecting species but not important to human cells. As you probably know, Domestos kills 99.9% of germs but you couldn’t use it as an antibiotic because it would also kill the vast majority of humans. Domestos is an example of a chemical which destroys both human and bacterial (and most other) biological systems.
Once we have found an biological system which is important to bacteria but not humans, we then design chemicals to specifically target that system. As bacteria are related (in terms of evolution), many of their biological systems are shared regardless of whether they are “good” or “bad” bacteria. For example, the first antibiotic discovered (called penicillin) targeted the bacterial cell wall. The system which it targets is present and vital in many bacteria and so it kills many different kinds of bacteria. For this reason, many current antibiotics also kill many different kinds of bacteria (i.e. both good and bad).
My work targets a system only found in MRSA so if it did work and eventually become a drug (unlikely but I can dream), it would be an example of an antibiotic which would not kill ‘good’ bacteria. There is quite a lot of work in this area ongoing at the moment. However, these kinds of antibiotics would be difficult to use as you would have to know what kind of bacteria is infecting the patient before you could prescribe it.
-
Ceri Dare answered on 7 Nov 2014:
No! As Sally says, there are some antibiotics which kill many sorts of bacteria, and some which are more specific and only target a few types of bacteria. But when a doctor sees someone who is ill, they do not know straight away what sort of bacteria are causing the illness, so they often use the antibiotics which kill EVERYTHING when that isn’t really necessary.
A project I am working on at the moment looks at which sort of bacteria are most likely to have caused a patient’s illness, so doctors can prescribe more targeted antibiotics, and not over-use the antibiotics which kill many sorts of bacteria. This is important because bacteria evolve to become more resistant to the antibiotics which are used most often, so we need to keep the antibiotics which kill everything in reserve for those patients who are very sick and really need them.
-
Marikka Beecroft answered on 10 Nov 2014:
No they can’t! Unfortunately they just kill or stop the growth of all bacteria. The way they kill bacteria is usually shared by all of them and so the antibiotic acts on all bacteria whether or not they are helpful to us.
Comments