But the most susceptible, the very young and elderly, can suffer deadly brain swelling. A new mosquito from Asia has been found in 35 places in Connecticut, causing concern that it could spread the potentially deadly West Nile strain of the encephalitis virus. In Unites States Army tests at fort Detrick in Frederick, Md., aedes japonicus, native to Japan and Korea, was found to be more effective than other mosquitoes at spreading the West Nile virus in a laboratory. But whether the insect will spread the virus in the wild is not known. In April 1999, scientists announced a search across Connecticut for japonicus after it was found on Long Island and New Jersey.
Scientists suspect the mosquito came to the Northeast in shipments of used tires from Asia.
Japonicus was found in Connecticut tire dumps last summer. The insect has since established itself in seven of the state's eight counties, said Theodore Andreadis of the Connecticut Agricultural Experiment Station.