Question

Now a days Corona viruses make havoc throughout the world and there is no single country

where no case of corona is found. Though all countries try to make vaccine for corona viruses

but no one get the success. Give the reasons why it is difficult to make vaccines for viral disease

as compare to bacterial or protozoanal diseases .​

Answer 1

Answer:

because they have simple structure cells and they are active only when they get host

Answer 2

Explanation:

For this corona virus, it has many legs I.e., it takes alot of time to kill one single corona virus. And the interesting fact is that if we calculate the whole weight of corona virus in whole world it is just 1 or 2 grams! I think this info is useful. Thank you