@Michael Bush
I wholeheartedly agree, these blanket sprays do more harm than good - not even counting all the side-effects, it is ineffective at it's one stated goal - to reduce the mosquito population. Where I am it's the same deal with Lyme disease and ticks, except there isn't even an option that I'm aware of like BTi that is specifically an acaricide without killing the majority of beneficial insects. Two years ago the area right behind my property was essentially swampland due to beaver activity (low, stagnant water), but there were so many dragonflies, bullfrogs, and bats that I might have had two mosquito bites in 4 years. Then somebody got the bright idea to knock down the beaver dams and drain the area, now I can't work outside for more than a couple minutes without getting stung. Natural ecosystems are the best at regulating parasite populations, our fear of nature is making it more virulent.