Alameda County added to its staff a new investigator to sniff out mosquitoes infected with West Nile Virus — a lively Labrador named Buffy, the county’s Mosquito Control District announced this morning. Abatement officials affectionately call her Buffy the Mosquito Slayer. The four-year-old dog detective picks up the scent of sitting water, a haven for the pesky bloodsuckers, in “covered utility vaults, crawl spaces of houses, and pipes half-hidden in hillsides,” according to an article today in the Contra Costa Times. Normally, it’s up to a human with a flashlight and a portable lab kit.