W. NILE SPRAYING MIGHT BE NEEDED COUNTY'S FOURTH DEATH FROM VIRUS CONFIRMED.

Byline: Troy Anderson Staff Writer

As the death toll mounts and the number of West Nile virus cases rises sharply, public health officials for the first time said Monday they are considering targeted neighborhood spraying to combat the spread of the potentially deadly virus.

Los Angeles County's fourth death from West Nile virus was confirmed Monday; the victim was 62-year-old Claremont resident and Green Party activist Walter Sheasby. His death is the seventh statewide this year from the mosquito-borne virus.

As a result, officials are considering spraying pesticides from trucks in some Los Angeles County neighborhoods.

``If the cases continue to mount as they are, it's likely we will be doing some (spraying) in the neighborhoods where we are seeing the most cases, at least where the cases are increasing dramatically,'' said Jack Hazelrigg, general manager of the Greater Los Angeles Vector Control District.

From Aug. 11 through Friday, the number of people in the county infected with the virus jumped from 32 to 81. Statewide, 249 confirmed human cases have been reported.

Officials estimate thousands of people have been infected, explaining that for every reported case, 15 to 30 people are infected but not tested.

``I computed a 32 percent increase statewide in less than 48 hours late last week,'' Hazelrigg said. ``It's nearly doubling each week.

``If that is really the rate and it doesn't slow down, you are easily looking at almost 1,000 (confirmed) cases by mid-September, just in Los Angeles County alone.''

Hazelrigg said he is considering using vector control trucks to spray ``pyrethroid pesticides'' in the air to kill adult mosquitoes.

Dr. Jonathan E. Fielding, the county public health officer, said this particular type of pesticide is among the safest and would be sprayed in ``ultra-low'' concentrations between dusk and dawn to minimize any adverse health effects on humans.

In the event a decision is made to spray the pesticides, Hazelrigg said he wanted to reassure the public that the insecticides are safe.

``What we use is 10 times safer than an aspirin tablet,'' Hazelrigg said. ``We use minute amounts of material and we don't use them over long periods of time.''

Exposure to pyrethroids, a neurotoxin, can irritate humans' skin and eyes and may cause numbness, headache, dizziness, nausea, vomiting, diarrhea and fatigue. In cases of severe exposure, fluid in the lungs and muscle twitching may develop, and seizures may occur.

Kelly Campbell, a spokesperson for the Pesticide Action Network North America, an international network that advocates replacing toxic pesticides with ecological alternatives, said officials used helicopters to spray pyrethroids in New York when West Nile virus emerged in the United States in 1999.

While a highly visible spraying program gives the impression that ``something is being done,'' spraying to kill adult mosquitoes is ineffective and may even increase mosquito populations by decimating mosquito predators, Campbell said.

Adrienne Esposito, executive director of Citizens Campaign for the Environment in New York City, said no one died from the targeted spraying in New York but many people reported suffering dizziness, nausea and feeling disoriented.

Doug Kelly, who oversees the vector control program in Denver, the epicenter of the virus last year, said the city hasn't sprayed any pesticides to kill adult mosquitoes but has engaged in a ``very aggressive'' program to kill mosquito larvae in stagnant pools of water.

``We have concerns about adulticiding, especially in a city environment,'' Kelly said. ``There is a certain amount of risk that comes with it and it isn't as effective as we'd like. It almost provides a false sense of security. You have to spray twice just to make sure. It has to drift into every area, including back yards, and that doesn't always happen.''

Hazelrigg said he'll have a better idea if the spraying will be necessary once he gets the results back soon on how successful efforts by his staff have been to spray larvicides - pesticides intended to kill mosquito larvae - in sewers, storm drains and flood-control channels.

Hazelrigg said he welcomed news last week that state lawmakers have proposed a bill that would allocate $775,000 to vector control districts statewide to combat the epidemic. He said he needs to double his staff of field workers - now numbering 28 - to adequately fight the virus.

``I don't feel we have enough coverage for the miles of underground storm drains that need to be treated,'' Hazelrigg said.

While conducting mosquito surveillance, Hazelrigg said his workers found hundreds of miles of storm drains in Los Angeles not included on maps made available to the vector control district. Many of those drains are located in the San Fernando Valley.

Troy Anderson, [phone]

troy.anderson(at)dailynews.com

VIRUS HOTLINES

To report stagnant or standing water, call the Greater Los Angele Vector Control District at [phone] or [phone]. To report a dead bird, call the state hotline at [phone].

For information on the DEET Education Program, call [phone] or log on to www.deetonline.org.

CAPTION(S):

box

Box:

VIRUS HOTLINES (see text)