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July 12 2016 – Dead Bird Infected With West Nile Virus Confirmed in Alameda County

First indication of West Nile virus in Alameda County for 2016

HAYWARD, CA – The Alameda County Mosquito Abatement District is reporting a dead bird that tested positive for West Nile virus. This is the County’s first indication of active virus transmission this year. The dead bird was collected from the City of Fremont on July 11, 2016.

The District is greatly increasing surveillance and larval control efforts throughout the area with the positive West Nile virus detection. Every effort is being made to locate areas of standing water where mosquitoes may breed including but not limited to catchbasins, stormdrain systems, and swimming pools. Neglected swimming pools continue to be a mosquito breeding issue in Alameda County. If you or anyone you know has an unmaintained swimming pool please inform the District so the proper treatment can be made.

“Southern Alameda County is a very active location for West Nile virus. Dead birds and mosquitoes from this area frequently test positive for West Nile virus,” says District Manager Ryan Clausnitzer. “We will continue to inspect and treat for mosquito larvae but we need the public to join us in the effort to reduce mosquito breeding sources by draining or covering all sources of standing water.”

As of July 11th, California has had 436 dead birds, 607 mosquito samples, and 12 sentinel chickens test positive for West Nile virus. The positive number of dead birds, mosquitoes, and sentinel chickens is higher than this time last year.

Reduce the risk of contracting mosquito-borne diseases by following these guidelines:

  • DUMP/DRAIN standing water on your property because that is where mosquitoes develop.
  • DAWN/DUSK is when mosquito activity peaks, so limit outdoor activities during this time.
  • DEFEND yourself when mosquitoes are biting by wearing long pants and longsleeved shirts and apply insect repellent containing EPA-registered active ingredients such as DEET, Picaridin, IR3535, and Oil of lemon eucalyptus.
  • DOOR/window screens should be in good repair with no tears or holes.

West Nile virus is transmitted to people and animals through the bite of an infected mosquito. There is no cure for West Nile virus. Approximately one in five people who are infected with West Nile virus will develop symptoms such as fever, headache, body aches, joint pains, vomiting, or rash. Less than one percent will develop a serious neurological illness such as encephalitis or meningitis. Adults over 50 years old and people with compromised immune systems are at increased risk of serious complications. Anyone who develops symptoms should seek medical care immediately.

Horses are very susceptible to West Nile virus and vaccines are available. Horse owners are advised to contact their veterinarians regarding timely vaccinations.

For information about mosquitoes, West Nile virus, or to request any of the District services visit or call (510) 783-7744. Residents can also request mosquitofish for their fish ponds, horse troughs, etc. at the District office located in Hayward at 23187 Connecticut St. For information concerning West Nile virus symptoms, prevention or testing please contact the Alameda County Public Health Department at (510)267-8001.