An infectious disease can be treated by the following two ways:

(i) Reducing the effect of the disease: In this method, medicine is given to the infected person for reducing the symptoms of the disease such as for bringing down fever or reducing pain. This practice is more focussed on healing the symptoms of the disease rather than preventing the disease. Although one can get rid of the body discomforts by using this method, the actual disease persists in the body.

(ii) Killing the microbe or pathogen that has caused the disease: In this method, the treatment is more focussed on removing the pathogen from the body rather than just lowering the symptoms of the disease. Although it usually takes more time than the previous method, it is more beneficial to the health.

Microbes can be killed in two ways:

(a) By consuming drugs that kill microbes specifically and does not harm the host body.

(b) By consuming drugs that block the essential biochemical processes of the microbe without harming the host cellular pathways: For this, antibiotics are given to the patient.