As the first Northern California West Nile virus death was reported, Sacramento County's aerial attack on disease-carrying mosquitoes shifted south Thursday and an emotional crowd confronted mosquito-control officials about the decision to spray pesticide above homes, parks and shops.
The San Joaquin County West Nile fatality, the fourth in the state this year, was confirmed as Sacramento County health officials tracked 10 new West Nile cases here, raising the county's total to 36.
The growing tally makes it even clearer that aerial spraying "has been the right decision," said Dr. Glennah Trochet, county public health officer.
Three nights of carpeting about 55,000 acres of northern Sacramento County with a fine mist of pesticide has "drastically" reduced mosquitoes, Dave Brown, manager of the Sacramento-Yolo Mosquito and Vector Control District, said at a Thursday morning press conference.
After another three days of spraying up to 66,000 acres in the southern county, Brown added, he hopes no more urban spraying flights will be needed this summer.
While Brown pronounced the north county spraying a success, saying it had killed an estimated 70 percent of adult mosquitoes, it met with mostly scorn and fury at a Thursday night meeting of the mosquito district board.
"It is not for you to decide how much risk I am willing to take," said Margaret Williams of Tahoe Park. "You tried to sneak this past the public."
As the meeting wore on, brisk Delta breezes briefly stalled the spraying, raising the prospect that fewer acres may be covered. Two planes took to the air to spread more of the pesticide from central Sacramento south through Elk Grove, but initially returned to the ground without spraying, said Dan Markowski, who is heading the spraying operation for Vector Disease Control, the Florida-based contractor hired by the district. Pilots tried again at 9:30 p.m. and were expected to spray successfully until midnight, he said, making it likely that they would fall short of their coverage goal.
Concerts and softball games were canceled in Elk Grove, and some schools planned to close play areas and wash down drinking fountains.
If weather conditions permit, the south county spraying is expected to continue from 8:30 p.m. to midnight today and Saturday, and officials urged people to stay indoors on what otherwise would be peak times for art lovers, outdoor diners and others enjoying summer weekend nights.
It's never wise to unnecessarily increase the pesticide "burden" already borne by the human body today, said Trochet.
"There are long-term impacts to any chemical that would accumulate in somebody's body ... or has to be metabolized," she said. "Some of the effects we know. Some we don't."
The small risk of spraying low levels of pesticide overhead, though, is far outweighed by the opportunity to save lives that could be lost to West Nile, she added.
While it most commonly passes with no symptoms at all, West Nile can cause nerve disorders and paralysis, and occasionally can kill.
Health officials offer this very rough estimate: For every 1,500 people infected with West Nile, 1,200 will have no symptoms at all - and one will die.
The vast majority of the rest will get a disease called West Nile fever, that can be as mild as flu or severe enough to cause weeks of missed school or work or even hospitalization, said Dr. Roger Baxter, chairman of infectious diseases for Kaiser Permanente of Northern California.
In roughly 10 of the 1,500 people, the virus will take a "neuroinvasive" form, attacking the nervous system. In that form, it can cause a type of meningitis that usually passes with relatively few side effects, or a type of encephalitis whose symptoms can linger eight months or more, or a polio-like "flaccid paralysis" that can end in permanent disability or death.
"It's bad," said Baxter. "You're really weak. You really do poorly."
West Nile has been marching steadily westward across the United States for the past six years. In California, it struck the southern part of the state first. In all last year, the state had 830 reported human cases and 27 deaths, nearly all in Southern California.
This summer, the disease moved north. A state Department of Health Services Web site reported 118 confirmed human cases as of Tuesday, with Sacramento County leading the state, and department officials late Thursday said the death toll has reached four. The latest victim was identified by neighbors as Jim A. Rodgers, 86, a World War II veteran and avid bowler who had lived in the town of Acampo, a little north of Lodi.
Three of the reported cases were in Placer County and one in Yolo County. Since most people infected with West Nile never know it, the numbers of reported cases are far lower than the number of people believed to have had West Nile.
Sacramento County announced its first two confirmed human cases in late July, and the numbers have been climbing ever since. In a county that had only three West Nile cases in all of 2004, the scope of this year's outbreak is sobering, Trochet said.
So far this summer, at least 14 people have come down with severe enough forms to be hospitalized, the doctor said.
West Nile has an incubation period of four to 10 days, and can be difficult to diagnose even when it causes symptoms, so people infected before spraying began could still be undiagnosed.
Doctors expect more cases, both in Sacramento County and statewide.
In their efforts to stem West Nile's spread, local mosquito control officials announced the aerial spraying program last week, saying they hoped to cover 71,000 acres in the northern county.
After some problems with airplane software, though, they cut back to 55,000 acres, excluding a wider band of land running alongside the northern edge of the American River than originally planned. That area was dosed from trucks.
During the southern application, a narrow band along the American and Sacramento rivers will not be treated aerially because curving lines of the waterway make it difficult for the planes, which follow long linear paths, Brown said. And the Greenhaven and Pocket areas are not receiving treatments by air because of the curving Sacramento River.
"We think we can do those areas better with ground rigs," Brown said.
The aerial spraying prompted precautions around planned outdoor events.
The Elk Grove Community Services District, which operates parks and the Fire Department, rescheduled its Friday night concert at Laguna Town Hall until Sept. 9 because of the spraying. Night softball games in Elk Grove were canceled Thursday and today.
The Farmers' Market in Elk Grove Regional Park closed at 7:30 p.m. instead of 8 so people could get home before spraying began, and early closings were planned for a skate park and aquatic center at Laguna Community Park.
Others plans were unchanged.
The Friday night concert at Cesar Chavez Plaza will go on as usual "because it's not a harmful chemical," said Melissa Carpenter, marketing coordinator for the Downtown Sacramento Partnership.
The Japanese Food and Cultural Bazaar will go on as scheduled from noon to 9 p.m. Saturday as well as Sunday at the Sacramento Buddhist Church on Riverside Boulevard.
"There is a little bit of concern, and we will wash everything down in the morning after the spraying," said Dana Ohara, a volunteer.
Second Saturday also will go on for art gallery owners throughout midtown Sacramento.
Steve Appel, owner of the Appel Gallery on T Street, has invited hundreds to the Saturday night opening of a photography exhibit by Elizabeth Carmel.
"Nobody has contacted me with any concerns about the spraying," he said. "I hope to go on as usual because it's a big show. If it doesn't go on as usual, that could be an economic problem for us."
Debate over the spraying roiled a crowd of roughly 100 people who gathered downtown at the County Administration Center on Thursday night, with many waving signs saying "Stop the Spraying" and "Leave My Home Alone."
The district's appointed trustees listened intently to speaker after speaker, occasionally answering questions but showing little emotion.
Laura Sinclair of North Sacramento told mosquito district officials that two of her dogs died on Wednesday, the day after her home was sprayed.
"I think this spraying should stop," she said, struggling not to cry. "You didn't have to kill my pets. ... This poison killed my babies."
Dr. Bill Durston, president of the Sacramento Chapter of Physicians for Social Responsibility, said the current outbreak of West Nile is no epidemic. "The likelihood of anyone in this room having symptoms of West Nile virus is very low."
The district should have taken more time to make sure the costs of spraying didn't outweigh the benefits, he said.
A few people, however, stood in support, saying the threat of West Nile virus needs to be addressed.
"I've discussed it with my family," said Christopher Voight, referring to his wife and three kids. "They are a lot more concerned with West Nile than about any detrimental impacts of the spray."
Sacramento County's total of West Nile virus cases rises to 36.
Residents express anger over the aerial spraying, but health officials say it is clear it "has been the right decision."
Spraying will continue tonight and Saturday night in south Sacramento County.
Officials say residents in the spray zone are not at risk and do not need to take precautions for themselves, pets or livestock. For those who remain concerned, they're suggesting ways to reduce exposure:
Stay inside and keep doors and windows closed between 8 p.m. and midnight. The mist stays in the air up to 90 minutes after release.
Turn off air-conditioning or ventilation systems during spraying.
Bring patio furniture, toys and pets indoors for the evening. Cover items left outside.
Remove shoes before coming inside until spraying ends.
Wash outdoor furniture and other items people may touch. But don't create pools of water that could become mosquito breeding grounds.
Fruits, vegetables and herbs from gardens should be washed but will be safe to eat.
Swimming pools do not need to be covered and will be safe for swimming after the applications.
For more information, call (800) 429-1022 or check www.fightthebite.net.
The killing agents in the insecticide - EverGreen Crop Protection EC 60-6 - are pyrethrins, extracted from chrysanthemum flowers. They are among the environmentally friendlier pest control options, killing insects on contact yet quickly disintegrating in sunlight, state regulators said.
People expose themselves to much higher levels of the same chemicals in spraying their homes, lawns and gardens with common insecticides. Pyrethrins also are contained in lice shampoos.
The insecticide also contains piperonyl butoxide. Though the U.S. Environmental Protection Agency has classified the chemical as a "possible" cancer-causing agent in humans and mammals, the agency rates it "low to very low" in toxicity.
West Nile prevention tips
To reduce the risk of catching West Nile virus, the Sacramento-Yolo Mosquito and Vector Control District recommends:
Use an effective mosquito repellent containing ingredients such as DEET, Picaridin or oil of lemon eucalyptus.
Repair tears in door and window screens.
Drain standing water.
Wear long pants and long sleeves outdoors when practical.
Avoid being outside at dawn and dusk, when mosquitoes are most active.
West Nile symptoms
About 80 percent of people who get West Nile virus have no symptoms, and 19 percent get flulike symptoms that include fever, aches and fatigue.
Fewer than 1 percent of West Nile victims will contract neuroinvasive disease, symptoms of which can include paralysis of the arms or legs, chronic headaches and chronic fatigue.
About the writer:
- The Bee's Carrie Peyton Dahlberg can be reached at (916) 321-1086 or firstname.lastname@example.org. Bee staff writers Phillip Reese, Deb Kollars, Erika Chavez, Cameron Jahn and Diana Lambert contributed to this report.