Two things about Mosquitos... Since this "infection" travels through the transition of blood, wouldn't mosquitos have some sort of impact? They arent even mentioned in the series. Plus there are plenty of animals for them to feast on so I don't believe that they would just die off... But I could see if the "infection" killed the mosquito. But with all the zombies walking around it is like a mosquito heaven.

Second, this has nothing to do with were alive but arent Mosquitos in general just zombies? The only difference I can think of (besides size, being able to fly, etc.) is that the breed. But there main goal in life is to eat you... (or suck your blood... Which is related to vampires... But that my friends is a different genre)