West Nile Virus Threat Increases In City

West Nile Virus Threat Increases In City

August 15, 2002

West Nile Virus has definitely arrived in Alexandria. "We expect problems until the first frost."

That was the assessment of Joseph W. Fiander, Senior Environmental Health Specialist, Alexandria Department of Health. "So far we have collected 21 birds in the city and confirmed that they died of West Nile Virus," Fiander said.

"We are still collecting birds but we have stopped checking for the virus," Fiander said. "We are now concentrating on the mosquitoes - what species, where, and time of years," he confirmed.

The greatest concern to the health department is that they think certain species of mosquitoes can "over winter" and, thereby, gain strength in the year to come. "Presently we have identified 20 species of mosquitoes in the city. Certain species can over winter in the storm sewers," Fiander explained.

"The city has hired a mosquito control company. They are trapping and testing mosquitoes to find out which species are the carriers. They are also treating our 6,500 storm water catch basins with larvicide to kill potential breeding grounds. The storm sewers are where they over winter," he said.

FIANDER URGED citizens to take extra precautions in removing those elements that tend to serve as mosquito breeding grounds. "The most numerous mosquito found within the city is what we call container breeders," he said.

"One dish under a flower pot can breed 500 asian tiger mosquitoes. These came to this country originally from Thailand. They are very aggressive and also attack during the day rather than at dusk or night like we are most used to," Fiander said.

"People should make every effort to remove potential breeding grounds, such as anything that contains standing water," he stressed. "It only takes one week for a larva to go from an egg to an adult mosquito."

Dr. Charles Konigsberg, Alexandria's Director of Health, recently announced, "Dead birds were found in all parts of the city including Old Town, Del Ray, Rosemont, Braddock Heights, Beverley Hills, South Pickett Street, West Braddock Road and Seminary Road."

He explained, "Most mosquitoes capable of spreading West Nile Virus to humans can breed in as little as a tablespoon of standing water." However, none of the mosquitoes trapped in Alexandria thus far have tested positive for the virus, according to Fiander.

"We know that it is in the bird population and that is why we have shifted our emphasis to mosquitoes," Fiander said. "With the confirmation of positive mosquitoes in adjacent jurisdictions, we are now treating West Nile Virus as endemic to the area."

The most vulnerable humans to the disease are those who have an impaired immune system, according to authorities. The only human casualty so far is a male in the District of Columbia who also suffers from leukemia, Fiander verified.

"I am answering complaints, making presentations to civic groups, and distributing brochures in or to educate the public about this threat," Fiander noted. "Public education is one of the most important parts of our program."

Konigsberg urged, "Persons who spend time outdoors should protect themselves by wearing long, loose fitting clothing and by using insect repellent."

WEST NILE VIRUS is spread to birds, humans, horses, and other mammals through the bite of an infected mosquito. Most people bitten do not get sick, according to health authorities. Those who do usually experience mild flu-like symptoms.

People over the age of 50 and those with diminished immune systems are most at risk, according to medical authorities. The most serious consequences are serious illnesses such as encephalitis, inflammation of the brain or meningitis, inflammation of the lining of the brain or spinal cord.

The Virginia Department of Health recommends the following to reduce exposure:

* Wear long, loose, light colored clothing,

* Use insect repellent products with no more than 35 percent DEET for adults and 10 percent for children,

* Turn over or remove containers where water collects,

* Eliminate standing water on tarps or flat roofs,

* Clean out birdbaths and wading pools once a week, and

* Clean roof gutters and downspout screens regularly.