Question

Why is it difficult to develop vaccine against viral disease

Answer 1

It is difficult to develop vaccine against viral diseases owing to several factors.

It has been observed that the bacteria during a viral disease become very weak. Hence, they cannot fight with the affected white blood cell.

Secondly one vaccine can fight only against one invader and not multiple bacteria.

With viral diseases once entering the body, require a new vaccine every time because once injected the bacteria becomes immune to them.

Answer 2

Answer:

making anti viral drugs is more difficult than making anti bacterial medicine because viruses have very few biochemical mechanism of ther own they make use of host machinism which replicates so it is very much difficult to find the target where these drugs get intfered by not making harm to host