CONCORD, CALIFORNIA - - The Contra Costa Mosquito & Vector Control District (District) announces that six more dead birds and one more chicken tested positive for West Nile virus. Four of the birds are American crows and two are Western scrub jays. Two birds were found in Brentwood, and one bird each was found in Bethel Island, Danville, Lafayette, and Pittsburg.  The virus-positive chicken is from Holland Tract.

"The cooler weather has been beneficial so far," said Deborah Bass, public affairs manager for the District.  "But the hot weather we are expecting may lead to greater mosquito populations and possible virus amplification, which is typical in the summer. In any case, we are working hard to keep the mosquito populations under control and ask the public to do the same. It's all about standing water-just dump it out."

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, 44 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 12 groups of mosquitoes, 58 dead birds and five chickens 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.