While that might not appear to be a health risk, the dish is one of many places mosquitoes can (and do) lay egg rafts, launching a new generation of little blood-suckers. When those airborne insects could be carrying West Nile Virus, the dog dish is indeed a dangerous prospect.

"We don't want people to panic," says Kriss Costa, community resource specialist for the Santa Clara County Vector Control District. "But we don't want them to become complacent."

Costa and health officials statewide and nationwide are warning that the risk of being bitten by a mosquito with the virus is higher than ever this year. Steady rain and slightly warmer-than-average temperatures have created the perfect breeding environment for mosquitoes, county vector ecologist Dan Strickman said.

"The set-up is about as bad as it could be," he said. "Although I suppose it could be warmer."

This has led to an earlier appearance of West Nile than in the past. A dead bird found in Willow Glen tested positive for the virus Jan. 3, and another from Santa Clara was confirmed Feb. 10. The first such bird last year was found in late January.

According to the national Centers for Disease Control and Prevention, there were 2,470 human West Nile cases in the United States last year, resulting in 88 deaths. While fewer than the 10,000 U.S. cases in 2003, when 262 deaths were attributed to the disease, the numbers rose in California last year.

State data from 2004 at westnile.ca.gov shows that 830 people were infected with West Nile Virus that year, 27 of whom died--a sharp increase from three infections in 2003.

Only one human case was confirmed in Santa Clara County last year, but Strickman said that is no reason to be less diligent in preventing the spread of the virus.

"In California, 58 percent of people who got infections had neurological disease," he said, referring to the more serious symptoms such as brain swelling and paralysis.

Even those symptoms that aren't classified as "serious"--such as fever, fatigue and muscle weakness--have lasting effects, Costa said.

"It is a very serious disease, and we're finding out that the mild, flu-like symptoms are more serious than we thought," she said.

People who started displaying those symptoms last summer are still feeling ill, she said, which has made some of them unable to work.

To keep themselves and their families from being bitten by mosquitoes, Costa recommended a number of practices that shorten the lifespan of mosquitoes. She said eliminating standing water around homes, including that in ponds, gutters and rain barrels, cuts down on the mosquitoes' ability to reproduce, at least near population centers.

Costa also recommends the home use of residual insecticides, which should be sprayed on the exterior of buildings and especially screen doors. Outside, people are urged to wear mosquito repellant with DEET and wear long-sleeved shirts and long pants to prevent bites in the evening hours.

Humans and birds are not the only ones affected. Of the 540 horses in California that had confirmed cases of the virus, 229 reportedly died or were euthanized as a result. There is more than one vaccine available for horses, and equine veterinarians recommend inoculating the animals at least once a year if not every six months.

"It's always a serious threat for horse owners, because it's always pretty darn near fatal when a horse gets it," said John Rosica, president of the Los Gatos Horsemen's Association. "They weren't taking it as seriously last year, but they are this year."

Rosica said that the elimination of standing water is just as important on properties with horses, as large puddles and ponds are very likely to form there. For those ponds that cannot be eliminated, mosquito-eating fish are available from the vector control district.

The district itself is trying new methods of controlling the mosquito population, Strickman said. This year, it is setting mosquito traps wherever there is a suspected infection, requiring increased cooperation from the medical community.

"I just came back from setting traps near where there was a suspected positive," he said. "Will that person end up being infected? Probably not. But a lot of making this work is getting the information in and then responding quickly."

Should trapped mosquitoes test positive for the virus, then the district will make a more concentrated abatement effort in the area they were found.

Strickman said he was a bit surprised that more birds have not been found with the virus in the county. So far, only 36 have tested positive from 19 counties in the state.

"Maybe that's a hopeful sign," he said.

West Nile virus protection tips

The Santa Clara County Vector Control District recommends the following
precautions to prevent the spread of West Nile Virus:

* Regularly check for and dump any standing water around your home--even very shallow puddles can produce hundreds of mosquitoes.

* Clear debris from gutters to prevent water from collecting there.

* Run pool filters every few hours rather than covering them.

* Spray the outside of your home with residual insecticides (available at hardware stores and nurseries). Use mosquito-eating fish (available from the district) or Bti larvicides in ponds or unused pools.

* Wear long-sleeved shirts and long pants when outdoors.

* Apply insect repellent with DEET to exposed skin when you will be outdoors at night. Apply repellant with permethrin to clothing, as mosquitoes can bite through fabric.

* When possible, avoid going outside at dawn, dusk and in the early evening, when mosquitoes are most likely to bite.

* Report any neglected pools and ponds or any problems with storm drains to the district.