Digital Extra

Now that another generally mild winter has changed to spring, health officials and others ask whether the West Nile-like strain of encephalitis found last summer in Connecticut and New York, in the latter of which it killed seven people, has been eradicated in the region. If the virus should become permanently established, it could emerge as a national public-health threat. "It will only be a matter of time before migratory birds carry it throughout the United States," said John Anderson, director of the Connecticut Agricultural Experiment Station.

The evidence so far indicates that the brain-infecting virus made it through the winter. Mr. Anderson recently confirmed an autopsy on a red-tailed hawk found in Bronxville, N.Y., in which the virus was present. Scientists also reported that the virus had been found in a sample of dormant mosquitoes from Queens.

The federal Centers for Disease Control has made a $200,000 grant to Connecticut to detect and analyze outbreaks of the virus in mosquitoes or larger animals, including people. Last year, when the West Nile-like strain was detected in the Western Hemisphere, hundreds of birds, mostly crows, were discovered to have died from the disease in Fairfield and New Haven counties. The 62 U.S. cases of West Nile-like virus all occurred in New York City and environs.

Connecticut proposes to avert another outbreak by widespread larviciding (al-though not aerial spraying) — spraying areas where mosquito larvae grow to prevent mosquitoes from maturing and spreading the virus to birds. The program also includes trying to reduce the areas of stagnant water; clogged gutters and catch basins, and rainwater that collects in old tires are prime concerns.

(Meanwhile, the trials to select finalists to represent the United States in the Olympic Games in Sydney in September have been relocated from the U.S. Equestrian Team headquarters in Gladstone, N.J., to Loxahatchee, Fla. The concern is chiefly about possible restrictions on tra-vel for horses exposed to the virus.)

In New York, which last year resorted to aerial spraying to contain the outbeak, the state health commissioner, Dr. Antonia Novello, has outlined a program similar to Connecticut's. Aerial spraying is only planned if the disease is seen as directly threatening humans. Other measures will include closely monitoring bird populations, and an early-alert system at area hospitals to identify symptoms or blood tests that may indicate the disease. In the vast majority of people infected with West Nile, for which there is no vaccine, there are few early warning symptoms — at most, flu-like signs, including muscular aches. Particularly in the elderly, the virus can infect the brain, causing swelling, sometimes killing the victim.

Swampy, mosquito-infested southeastern New England is in the line of fire for this disease, and officials in Rhode Island and Massachusetts are testing mosquito and bird populations and preparing a larvacide program if the virus should ap-pear. Meanwhile, it is good to see that health officials, such as Rhode Island's health director Patricia Nolan, have been preparing to meet any challenge. from this disease.