When mosquitoes brought West Nile virus to New York, all the papers said it was going to be the next big deadly epidemic (which, of course, it wasn’t). The day the news came out, I was in my garden in Pittsburgh, and a mosquito landed on my arm. I smacked it, then immediately thought, “Oh my god! West Nile virus!” So I ran inside and did something I hadn’t done since grade-school summer camp: I doused myself with insect repellant. Then I got a whiff of the fumes and remembered I just read an article saying insecticides cause Parkinson’s disease!