First there was Lyme disease.
Then came two malaria-like infectious diseases, babesiosis and anaplasmosis.
Now a new study indicates that an unexpectedly high percentage of black-legged ticks in the mid-Hudson Valley also carry a virus that can cause swelling of the brain and, in some cases, death.
The study, published today in the journal Parasites and Vectors, found a variant of the virus responsible for Powassan encephalitis was present in ticks collected over a five-year period in Dutchess, Ulster, Putnam, Westchester, Orange, Rockland and Sullivan counties.
The rates of infection among the ticks were higher on the eastern side of the Hudson River, as high as 6 percent among the dozens of sites that were sampled.