Why do specific mosquitoes carry specific diseases?

Question

For instance, the Aedes mosquito carries dengue fever tho' there may be malaria victims in the area as well.

Answer 1

they are of different breed so they carry different genes

Answer 2

kinda like they say we cant get HIV from them,but the female can carry it, and we can get the westnile and malaria but is it still only the female in all these cases my guess if they can get it they can give it,no matter what its their revenge on mankind,and mother natures helping