Analysis of Bacillus sphaericus in controlling mosquito populations in urban catch basins.

The West Nile virus (WNV) is a mosquito-borne infection that can be fatal to humans, equines, and avians, among others. WNV was first introduced to the United States in 1999 and is rapidly spreading across the country. Urban catch basins are thought to be prime breeding sites for mosquitoes, especially those identified as WNV carriers. The pilot study reported here was conducted in a city in southeastern Pennsylvania where there are 70,000 catch basins. The purpose of the study was 1) to determine whether catch basins are breeding sites for mosquitoes and 2) to test the effectiveness of a larvicide that uses a bacteria, Bacillus sphaericus, to eliminate mosquitoes in urban catch basins. The two-pronged study determined that catch basins are ideal locations for mosquitoes, especially Culex pipiens, and that B. sphaericus is an effective larvicide.