Beyond DEET: New-Age Mosquito Control

West Nile virus (WNV) and St. Louis encephalitis (SLE) have become significant health concerns. Although most people who become infected with either disease show no symptoms or only mild ones, WNV killed 284 people and made more than 4,000 clinically ill in the United States last year. And on average, 128 cases of SLE are reported annually.

One mosquito genus, Culex, has been shown to transmit both WNV and SLE. ARS scientists have discovered and patented a new baculovirus a virus specific to arthropods, called CuniNPV that kills Culex mosquitoes. Stable and persistent, the virus is a promising candidate for development as a larvicide. The patent includes a method for transmitting a virus to the mosquitoes. The baculovirus is activated by mixing with magnesium. When the mixture is added into any body of water where mosquitoes breed, the larvae ingest it; the result is 85 to 95 percent kill after 2 to 3 days. There is no harm to other organisms or to the water.