Local health officials are nowhere close to smacking their panic buttons, but they are asking Marin and Sonoma county residents to help cut the risk of seasonal West Nile virus now that four birds in the two counties — including one in downtown Novato — have fallen victim to the disease.
The Marin/Sonoma Mosquito & Vector Control District said an infected dead bird, a scrub jay, was found Aug. 7 just off Grant Avenue in Novato and three other infected birds have been collected in Sonoma County, the most recently two in Santa Rosa.
There haven't been any human cases of West Nile in Marin this year — in fact not since 2006, according to Marin County's Department of Health and Human Services.
"This risk is present because it's always in the environment, but we're not on high alert," said Dr. Craig Lindquist, the county's interim public health officer. "We are observant and recommending that the public follow the Three D's."
That would be drain areas of standing water, wear protective clothing at dawn and dusk, and use insect repellants such as DEET or organic oils. (Lindquist laughed when it was noted that it was four D's, but he said health officials only count dawn and dusk as one).
Lindquist said West Nile has been reported in some form in 32 California counties this year and that there have been some human cases of it. Just one, in Kern County, proved fatal.
Piper Kimball, who directs scientific programs for vector control, said the threat to human health can't necessarily be tied to the dead bird count. Two of the dead birds in Marin and Sonoma counties were classified as positive-recent, meaning they had been infected this season and would pose an increased risk of virus transmission from mosquitoes to humans. Two other dead birds were positive-chronic, meaning the virus levels were low and would not likely propose a threat to people.
Approximately 80 percent of people who become infected with West Nile won't show the typical symptoms, such as headache, fever, body aches, vomiting, nausea, swollen lymph glands and skin rash on the chest, stomach and back. However, the remaining 20 percent of infected people will develop West Nile fever, according to the vector control board.
Of those people who get infected, less than 1 percent will suffer a severe case such as high fever, headache, neck stiffness and disorientation. Only in the most extreme cases, people will fall into a coma, experience paralysis or die.
Here are some ways to reduce the threat of West Nile virus transmission, according to vector control:
- Eliminate unnecessary standing water in discarded tires, buckets, kiddie pools or any other item that can hold water for more than a week.
- Report mosquito problems, neglected swimming pools, or any area that could be producing mosquitoes.
- Stock backyard ponds or other permanent water features with mosquitofish. The fish are free and can be delivered or simply picked up at the District office.
- Report dead birds to the West Nile virus hotline at 1-877-968-2473.
- Wear mosquito repellent when outdoors during dusk and dawn. Use a repellent containing one of the following active ingredients: DEET, Picaridin, oil of lemon eucalyptus, or IR3535.
For more information or to report mosquito problems contact the Marin/Sonoma Mosquito & Vector Control District at 1-800-231-3236 or visit www.msmosquito.com. Report dead birds to the West Nile virus hotline at 1-877-968-2473 or online at www.westnile.ca.gov.