Much smaller much Stronger

Surprisingly most people categorize all diseases in one single class that is “Infection” and consequently they are confused about them. Knowing how to cure a disease is essentially dependent on knowing its cause. Many infectious diseases are caused by harmful viruses and bacteria. But differences between viral and bacterial infections are mostly related to their biological, physical and epidemical characteristics which make them totally different to confront.

    First of all, viruses are not real living creatures. They are just special mere molecules resistant to antibiotic which can only replicate themselves in other living organisms. On the other hand, bacteria have cell-walls and active protoplasm sensitive to antibiotics. This is why viruses can stay dormant in diverse climates for years but bacteria are easily destroyed even by being exposed to sun light or dry environment. 

    The second difference is the size of these pathogens. Viruses are much smaller than bacteria. A single bacterium itself has the room for five thousand viruses in average and this extreme smallness makes viruses hard to be filtered in comparison with bacteria. Also these ultra-tiny viruses, hidden in other cells are nearly free from contact to drugs while bacteria are not so. 

    The last but not the least is the epidemical difference between these disease-causing germs. While bacteria are spread around by close contact to dirty objects or contaminated food and water, viruses can be easily spread out even by air. This shows that why epidemic bacterial illnesses are rare but viral disease outbreaks are quite common.

   These differences reveal that why we are unable to wipe away viruses to mention a few HIV (Human Immunodeficiency Virus), HSV (Herpes Simplex Virus), and most recently EBOV (Ebola Virus), but we have been able to eradicate or at least control bacterial epidemics like Cholera (known as Black Death in old times) and Typhoid. These fundamental differences also make doctors prescribe a great deal of antibiotics when you have bacterial diseases say gastroenteritis but only recommend you “stay in bed and have some hot soup” when you get a viral illness like common flu.

TOEFL listening lectures: A university lecture by a professor of Physics

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