That being the case, we have to especially worry about those species which have low populations. He's anxiously monitoring the state's bald eagles for signs of the virus, although none of the approximately 200 birds has been affected so far. Given the proliferation of West Nile virus in the Northeast, there's little doubt the virus is here to stay. But there is new evidence that has Stone and others wondering whether there's more to this exotic virus that has yet to be learned. Over the summer, a young raccoon and two species of bats found dead in New York turned out to be infected with West Nile virus.
Birds are highly susceptible to West Nile virus, and are thought to be the only viral reservoirs.
It also might not be so apparent, he said, because animals have had generations to build immunity to the virus. And if we've got the virus in these two, it's entirely logical that we're going to find it in a number of other mammalian species in the Western Hemisphere. The cause could be any number of things, such as pesticides or harsh weather conditions. Bats are especially difficult to test because of precautions against rabies. But most laboratories are focused solely on testing wild birds as part of the multistate surveillance system, and cannot spare the time or limited resources looking at how West Nile virus may be affecting other animal species.