While no cases have yet been reported in Hawai'i, Department of Health vector-borne disease coordinator Shokufeh Ramirez says there is a higher probability of West Nile spreading to the Islands than last year.

"For us it does seem more of a threat than last year particularly because there is increased activity in the western part of the U.S.," Ramirez said. "Compared to last year at this time, there are more cases on the Mainland reported and from more states."

So far this year, 182 human cases and four deaths due to West Nile have been reported in the United States. "It seems that there is more of a likelihood that an infected bird or mosquito could get here as compared to last year," Ramirez said.

A new survey effort by the Department of Health and Hickam began in April to look for breeding areas around the state. Points of entry on each island such as airports and harbors were examined for infected flies.

"We feel the likely entry into the state would be on a ship or plane with infected mosquitoes," Ramirez said. "While we do have the ocean around us as a natural barrier, because we have so many ships and goods coming in and we have regular flights from the Mainland, there is that threat."

Hickam residences have been systematically surveyed for West Nile. The base makes a good testing ground because of its proximity to Honolulu International Airport. To date over 16,000 mosquitoes have been tested for West Nile.

"If the virus does arrive in Hawai'i, we want to quickly detect it," said Gregory Olmstead, program manager for the Department of Health's Vector Control Branch. "It's one of our highest priorities."

Robert Lopes, vector control inspector for the state Department of Health, examines traps holding mosquitoes that are to be tested to see whether they carry the West Nile virus.

West Nile virus is a disease usually passed between birds and mosquitoes. While dead birds that died of West Nile cannot transmit the disease, humans who are bitten by mosquitoes with the virus can be infected.

One in 150 people generally becomes severely ill from the disease. Of those, 10 percent to 15 percent may die from West Nile.

Symptoms of West Nile can include fever, headache, body aches, swollen lymph glands and skin rash. In rare cases people will develop encephalitis.

Lopes, section supervisor in the vector control branch, says four to six inspectors go together on routes around the base and near the airport.

"They treat it routinely each week," he said. "Hopefully once we start treatment, then these large numbers of mosquitoes will go down. That way we know we are successful in treating them."