tl/dr for the data:

Blood meals consumed by 24 mosquitoes could be identified and were sourced from 18 humans, one amphibian, six birds, one canid, and one mouse.

I wonder if this isn't the result of natural selection. As in: mosquitoes that are better at detecting humans have better odds of reproduction than the ones focusing on different prey. Perhaps it's attraction towards some molecules humans release into the air, or even to night lights.

Well..yeah. we're the only things left to hunt so the human hunting mosquitoes will do the best.