Hard to choose between rats/mice and mosquitoes
Rats and mice are relatively harmless and rarely actually attack people like mosquitoes but on the other hand they’re way harder to get rid of. If you see one mouse in your crib you most likely got at least 10 whereas you usually only have to deal with mosquitoes one (or small amount) at a time and can be confident they’re gone when you don’t see them anymore.
And mosquitoes literally kill more humans than any other living creature.