CBSE Class 9 Answered

i) Once someone has a disease, their body functions are damaged and may never recover completely.

ii) Treatment of a disease takes time, which means that someone suffering from a disease is likely to be bedridden for some time even if given proper treatment.

iii) The person suffering from an infectious disease can serve as the source of spread of infection to other people. This leads to multiplication of the above difficulties.

Due to these 3 reasons, prevention of diseases is better than their cure.

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