Eastern equine encephalitis has been confirmed in found in mosquitoes in Halifax, Massachusetts.

Massachusetts health officials warned that the risk of mosquito-borne disease was growing after 16 more samples tested positive on Wednesday for West Nile virus in the Boston, Holbrook and Kingston regions.

Meanwhile, health officials on Long Island, New York say they have completed aerial spraying against the West Nile virus in Nassau County.

Eleven West Nile virus have been reported there so far this year, with three suspected deaths. During 2007 only two cases were reported.

There have been 500 cases of West Nile virus reported nationwide so far this year. Mosquito season continues as late as November.