The legal context of mosquito control for West Nile Virus in New York City

West Nile Virus (WNV) is one of a number of microorganisms spread to humans by the bite of an infected mosquito. Although most WNV infections are mild or cause no symptoms1 severe WNV infection involving the brain (encephalitis) may cause long-term disability2 or death.3 WNV has spread throughout much of the eastern half of the United States4 following its unexpected arrival in the New York City (NYC) area in 1999.(5) It has now spread to many western states. In 1999, 2000, and 2001, NYC experienced 45, 14, and 7 severely ill persons, respectively, including 5, 1, and 0 deaths. Responsibility for the surveillance and control of mosquito-- borne infections in NYC rests primarily with the NYC Department of Health and Mental Hygiene (the Department). In addition to undertaking public and professional outreach, the Department has acted throughout NYC to reduce the risk of human WNV infection by either eliminating mosquito breeding sites or by treating breeding sites to prevent developing (or larval) mosquitoes from emerging as biting adults, and by spraying pesticides to reduce the number of adult mosquitoes in selected areas determined to be at an increased risk for human WNV infection. This article summarizes the legal and regulatory context of larval and adult mosquito control to address WNV.