Speciation, the evolutionary process by which new species are formed, is clearly responsible for the ultimate generation of species diversity over geologic time.
I'm a bit confused about this question. But I will try my best to answer. :)
To prevent a certain virus, or increase someone's immunity towards a virus, doctors give patients a shot/vaccine. For example, people get a flu shot yearly to help prevent them from getting the flu. The shot contains a small portion of the flu itself. The flu remains dormant until the body decides to activate it or fight it off. This also helps the body become more immune to the virus/sickness and fight it off easier.
I hope this helps! :)
