CONCORD, CALIFORNIA - - The Contra Costa Mosquito & Vector Control District (District) announces that 12 more dead birds are positive for West Nile virus. Ten of the birds are American crows, one is a Western scrub jay, and one is a red-shouldered hawk. Five birds were found in Brentwood, two each in Discovery Bay, Pittsburg and Walnut Creek, and one in Antioch. Location details of the birds are listed on the District 's website.

"August and September are critical months for West Nile virus," said Steve Schutz, Ph.D, scientific program manager for the District.  "The mosquito species that can transmit West Nile virus are plentiful enough that they start feeding more on people as well as birds. Sometimes, there just aren't enough birds to go around."

Birds are the reservoir for West Nile virus. The two species of mosquitoes in Contra Costa County capable of transmitting the virus prefer to feed on birds; however, people can become infected when a mosquito bites an infected bird and then a person. West Nile virus symptoms of the mild form include fever, headache, tiredness, body aches, and swollen lymph glands. While the illness can last only a few days, even healthy people have reported being sick for several weeks. West Nile virus of the severe form can be fatal.   

• Dump or drain standing water. Mosquitoes can't begin their life without water.
• Defend yourself against mosquitoes using repellents containing DEET, Picaridin, or Oil of Lemon Eucalyptus.
• Avoid being outdoors when mosquitoes are present, typically dawn and dusk.
• Report neglected swimming pools by calling 925-771-6195 or visiting www.ContraCostaMosquito.com  Anonymous calls accepted. Just one neglected pool can produce more than 1 million mosquitoes and affect people up to five miles away. 

Since 2005, 42 people in Contra Costa County have been diagnosed with West Nile virus. In 2006, two people died from the disease. Recent studies have shown that the majority of cases are not diagnosed and grossly under reported. For 2013, a total of four groups of mosquitoes and 31 dead birds have tested positive for the virus.  

Visit the District's website or click on these links for  current West Nile virus activity  or to  receive automatic emails for when the District fogs for adult mosquitoes.

Contra Costa Mosquito & Vector Control District, an independent special district and public health agency, is located at 155 Mason Circle in Concord. Call the District to report mosquito problems at (925) 771-6195 or visit their office between 8:00 a.m. and 4:30 p.m. to get FREE mosquitofish for ornamental ponds, horse troughs or neglected swimming pools.