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August 31, 2023  Adult Mosquito Control Scheduled in Eastern Livermore Area to Suppress West Nile Virus Activity

HAYWARD – Due to the increased West Nile virus activity in the eastern Livermore area, the Alameda County Mosquito Abatement District will be treating adult mosquitoes on Tuesday, September 5th, depending on weather conditions. District personnel will apply Evergreen ULV (5-25) Ground Public Health Insecticide by a truck mounted ultra-low volume sprayer. The treatment area is limited. Patterson Pass Rd is the northern boundary; S Vasco Rd is the eastern boundary; East Ave is the southern boundary and N Mines Road is the western boundary. A map of the treatment zones can be seen below.

Livermore has had a number of West Nile virus positive dead birds, and two groups of positive mosquitoes in the treatment area. General Manager Ryan Clausnitzer explains “We expect a quick and effective response by our team will suppress the mosquito population and lower the risk of residents contracting West Nile virus.” Residents are encouraged to stay indoors during the spraying hours, which are limited to nighttime. The insecticide will break down in sunlight. To learn more about spraying for adult mosquitoes, see our website,

Effective mosquito control relies upon residents to do their part. Residents are urged to be proactive by eliminating sources of water where mosquitoes can breed, such as plants, outdoor containers, unmaintained swimming pools and other cryptic places. Residents should also protect themselves from mosquito bites by wearing long loose clothing, repairing or replacing window screens in their homes, and wearing insect repellent in mosquito heavy areas. If you come across a dead bird please report it by calling (877)WNV-BIRD or online at 

The District continues its mosquito surveillance and larval control program throughout the county, alongside our response to West Nile virus in the county.

As of August 30th, California has had 354 dead birds, 2,797 mosquito samples, 102 sentinel chickens, and 55 humans test positive for West Nile virus. Five people in California have died from West Nile virus this year. Due to the heavy rain from the winter, along with scattered showers in spring and summer, the numbers of West Nile virus cases in birds, mosquitoes and humans are higher this year than last year.

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, however vaccines are available. Horse owners are advised to contact their veterinarians immediately about timely vaccinations.

For information about mosquitoes and West Nile virus visit our website: Residents can request mosquitofish for their fish ponds, horse troughs, etc. by contacting our District office. We are located in Hayward at 23187 Connecticut St. Our phone number is (510)783-7744. For information concerning West Nile virus symptoms, prevention or testing please contact the Alameda County Public Health Department at (510)267-8001.

Contact for media inquiries:

Judith Pierce, MPH

Public Outreach Coordinator



Adult mosquito control area in purple:

Patterson Pass Rd is the northern boundary; S Vasco Rd is the eastern boundary, East Ave is the southern boundary and N Mines Road is the western boundary. 


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