Question

Why it is difficult to make anti-viral medicines as compared to antibacterial medicines?

Answer 1

Members of a group microbe have similar biochemical process inside their cells. So, drugs that block these biochemical mechanisms in one member of the group will be effective against many other members of the group. The same drug will not be effective against a microbe belonging to different group. 

Antibiotics commonly block biochemical pathways important for bacteria. These kill the bacteria by inhibiting its growth. But the same antibiotics do not work on viruses. Because viruses do not use biochemical pathways such as bacteria and they have few biochemical mechanisms of their own. 

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