It's not exactly London during the blitz, but residents throughout Nassau and Suffolk counties have had their anxiety levels heightened considerably over insecticide spraying exercises taking place on the island. The purpose of the spraying is to kill mosquitoes carrying the West Nile-like encephalitis infection.

Dr. Rick Conetta, the director of Critical Care Medicine at Flushing Medical Hospital and a resident of Roslyn, was the first doctor to notice an "unusual, infectious problem" circulating throughout Queens County. The first four encephalitis cases came to Dr. Conetta. He reported them to his colleagues at Flushing Medical, who then passed on the information to the New York City Department of Health.

"I had never seen anything like it," Dr. Conetta recalled. Further research found the disease to be a "West Nile" form of encephalitis which can be fatal to the victim.

At first, the Department of Health was not interested in the hospital's daily reports. But once birds began dying at the Bronx Zoo, city officials started to notice. And so, the spraying began.

Mosquitoes carry the disease. They pass it on by biting humans or their fellow mammals, usually birds. And while residents remain anxious about spraying runs on their villages, they should be more afraid of the infection, Dr. Conetta added. The elderly are especially affected by any mosquito bites. Here in Nassau County, a 76-year-old Mineola woman, who also suffered from diabetes and was legally blind, recently died from a bite. In Queens County, Dr. Conetta said another elderly woman died even after her neighborhood had been sprayed.

There is no specific treatment for the infections. Doctors support encephalitis victims by giving them plenty of fluids and solid foods, while the body fights off the infection. Young people who are in good health can generally overcome any mosquito bites. According to Dr. Conetta, there have been very few cases of the infection in young people.

The elderly, especially those suffering from other, chronic problems, have a much more difficult time. Once bitten, they often become feverish, weak, and confused.

How did the infection come to New York? That's the big question and no one, Dr. Conetta said, has an answer so far. Right from the beginning, officials have suspected it may be a form of bio-terrorism. That is, the disease was intentionally "planted" by foreign hostiles. The disease may also have been introduced unintentionally by other foreigners entering the country.

Most cases, so far, have been reported in New York City. There have been 40 reported cases in the city, as opposed to only 15 in the suburbs, which include Nassau, Suffolk, Westchester and several New Jersey counties.

Still, Dr. Conetta calls the disease a "growing problem." The number of cases reported represent a large increase from when the infection was first noticed. But just because several dozen cases are on the books, that doesn't mean only 55 people have been bitten. According to Dr. Conetta, for every person reported with encephalitis, up to "300 or 400" have also been bitten by a mosquito carrying the infection. So, several thousand people in both the city and suburbs have been bitten; however, their own bodily systems are able to fight off the bites, making them unaware they were ever infected in the first place.

While the human population is holding up okay, the crow population on the island is taking a big hit from the infection. According to Dr. Conetta, over 1,000 crows on the island have been killed by the infection. Dr. Conetta himself has noticed that since the spring, he doesn't see many crows in the backyard of his Roslyn home, a sight that was once a common occurrence.

The next big question, according to Dr. Conetta, is what to do about next spring and summer. For now, the spraying will continue until the first sustained winter frost kills off the mosquito population. But come next year, will there be spraying already scheduled, or will the authorities wait to see if there are any new cases? In the meantime, doctors and researchers hope to find out how the disease came to New York and how it can be prevented from starting up again.