Posted on Fri, Jul. 07, 2006

Mosquito spraying aimed at West Nile

Mercury News

Pyrenone 25-5. Before the summer is over, many Santa Clara County residents may learn first-hand about the insecticide used to kill the mosquitoes that carry the West Nile virus.

County vector control crews were scheduled to spray the chemical in a fine mist through parts of West San Jose and Saratoga overnight, and officials say this will probably be the first of several such efforts to combat a disease that poses a serious threat to humans.

``It's very likely we will be repeating this somewhere else in the county,'' said vector control district spokeswoman Kriss Costa, citing the fact that the virus has shown up so early.

Last year, it wasn't until August that dead birds were found that tested positive for the disease. In 2005, 935 Californians were infected with West Nile virus, 19 of them fatally.

Residents in the fogging area may notice a slight odor this morning, but Costa said most won't notice any effect from the spraying, which was to occur between midnight and 4 a.m.

Crews targeted a 62-mile residential area around Prospect Road and Johnson Avenue. Two groups of mosquitoes infected with West Nile virus and several dead birds that tested positive for the disease have been found there.

Though vector officials say the action is needed to stop the disease from spreading to humans, some residents were worried about the insecticide.

San Jose resident Marsha Miliman lives outside the fogging area, but she said she is sensitive to chemicals and worries that the mist could drift her way. She was among an estimated 800 people who attended a community meeting Wednesday at Lynbrook High School about the fogging. Miliman said she was not swayed by county health officials, who assured the crowd that Pyrenone 25-5 is safe.

``No pesticide is without health consequences, which are greater, or at least equal to, the threat caused by West Nile virus,'' Miliman said in an e-mail.

Costa said Pyrenone -- the active ingredient used in shampoos for dogs and to treat children with lice -- is safe for people and pets, but advises anyone with health concerns to consult a physician.

On Thursday, technician Mario E. Ramirez made rounds through the neighborhood to ease people's concerns.

``I had several people who stopped me on the road and asked me about the fogging,'' Ramirez said.

He told those worried about health and environmental effects that the insecticide, which was used last year in the Almaden area of San Jose, leaves no residue but that they could wash down patio furniture the next day if they wanted to.

``It's not a health hazard to them, only to mosquitoes,'' he said, but noted that keeping windows closed during the spraying is one way to prevent the insecticide from entering homes.

For more information about the West Nile virus and the fogging procedure, visit or call (408) 918-4770.

Contact Yomi S. Wronge at or (408) 920-5744.

© 2006 and wire service sources. All Rights Reserved.