Eli5: What do deadly viruses/parasites get out of killing their hosts?

Question

Surely it is easier to spread through a living host?

In: 3

Answer 1

Viruses and parasites don’t “care” about their long term success, or more accurately, don’t have any ability to understand it. Each individual is just trying to make more of itself. If doing that causes collateral damage that ultimately snuffs out them in general because the host wasn’t able to pass them along to other hosts, the individual still was successful in making copies.