Birds, particularly crows, blue jays and hawks, are highly susceptible to the virus, but many species of mosquitoes that bite birds don't bite people. And tests on more than 10,000 mosquitoes did not find the virus in a single one. Spraying will take place only when a team of mosquito-control experts determines that the public is at substantial risk of being bitten by infected mosquitoes. Determining that risk, Grant explained, will involve weighing many variables, including whether other mammals have become ill, whether many infected mosquitoes have been found and whether those mosquitoes are in a densely populated area. Even then, the state team will merely be making a recommendation to the municipalities, and providing the supplies, Grant said.
Municipalities can reject the advice and decline to spray.
But the state will not provide insecticide to municipalities if it doesn't think spraying is warranted. Asked why the state is trying to avoid spraying when it has always maintained that the chemicals were safe, Grant said that spraying is now seen as a waste. The DEM has always acknowledged that the spraying can cause breathing difficulties in people with lung disease and can kill desirable species of insects. We've learned something, and we've moved on. Westerly, which recorded 41 birds killed by West Nile, saw the most spraying last year.