When I qualified as a naturopath, I remember one of the questions I had in my exam was, in your opinion, what do you think the biggest breakthrough in medicine is? I had to say the discovery of the antibiotic by Alexander Fleming, although the discovery was found purely by chance, due to a contaminated Petri dish. The mold that had contaminated the dish turned out to contain powerful antibiotic called penicillin. This antibiotic will only get rid of harmful bacteria not a viral infection.
During winter our bodies are at their lowest, so I would say that many of us do catch some sort of viral infection, be it ears, throat, chest. I hate to say but people always go for the quick fix, even if that fix is not appropriate. The antibiotic should be taken when you have a bacterial infection not a viral infection. The only thing that the antibiotic will do is kill the good bacteria in the gut as well as the bad, eventually causing an imbalance in the gut, which then causes other health issues.
Often the GP will take a swab or a urine test to find out if you have any harmful bacteria. If you try to minimise taking antibiotics your immune system will response much better to infection. People often ask my opinion about taking these, and my response to them is these should be taken when needed. Our immune systems are very proactive and efficient in getting rid of viruses. When you feel run down make sure you get enough rest, eat well and try to limit anything in excess!
Viruses are also caught from others; make sure that you always wash your hands. You have to stop viruses from being able to reproduce and release new viruses into your body, or stop them from being able to get inside your cells in the first place.