Comment by billions

It is theorized there is no adverse effect from killing mosquito species. There is always a counter-effect. Typically it's unpredictable. Mosquitoes FACILITATE transmission of bad stuff. I believe that if bad stuff is not transmitted, species evolve more slowly against pathogens. Species will still be exposed, maybe generations later through a scratch or otherwise. At that point, having never evolved a strong immune system the same animals will be less prepared. It's not whether the American Indians were to die from European diseases, but when.