San Joaquin County Mosquito & Vector Control District

🦟🔬 Advancing Mosquito Control Through Research and Collaboration

At San Joaquin County Mosquito & Vector Control District, our work is guided by science. Our District entomologists and laboratory staff conduct mosquito surveillance, species identification, and disease testing to help protect public health and guide mosquito control efforts throughout the county.

We're also proud to partner with University of the Pacific on research that helps answer important questions about mosquitoes in our community. One ongoing project, presented preliminarily at the 2025 Mosquito and Vector Control Association of California Annual Conference and receiving 2nd place in the William E. Walton Poster Session, is investigating host preferences through bloodmeal analyses of the invasive 𝘈𝘦𝘥𝘦𝘴 𝘢𝘦𝘨𝘺𝘱𝘵𝘪 mosquito compared to our indigenous 𝘈𝘦𝘥𝘦𝘴 mosquito species in San Joaquin County. Preliminary bloodmeal analyses found that a majority of invasive 𝘈𝘦𝘥𝘦𝘴 𝘢𝘦𝘨𝘺𝘱𝘵𝘪 blood meals were derived from humans with a smaller percentage from dogs or cats, while blood meals from indigenous 𝘈𝘦𝘥𝘦𝘴 species were primarily from livestock or small mammals.

This research project is being led by Pacific graduate student Lemya Mohamed under the mentorship of Dr. Tara Thiemann, Professor of Biological Sciences and Co-Chair of the Department of Biological Sciences, in collaboration with our District entomologist, Dr. Huang, and laboratory staff.

By combining field surveillance, laboratory science, and academic research, we're working to better understand mosquito behavior, assess public health risks, and develop effective solutions for our community. We look forward to following this research as it progresses and sharing future publications and findings.

The San Joaquin County Mosquito & Vector Control District remembers the life and legacy of former District Manager and Board Trustee, Jack V. Fiori, who passed away on May 15, 2026, at the age of 95.

Mr. Fiori dedicated more than 60 years of service to mosquito and vector control in San Joaquin County. He joined the District in 1955, serving 36 years as an employee, including 15 years as District Manager. After retirement, he served an additional 25 years on the Board of Trustees representing the City of Lodi, including two terms as Board President.

His decades of dedication, leadership, and commitment to public service left a lasting impact on the District and the community we serve. We extend our sincere condolences to Mr. Fiori’s family and loved ones.

Sacramento has detected their first West Nile virus (WNV) positive mosquitoes of the season.

While we have yet to detect WNV activity within San Joaquin County so far this year, WNV is endemic in our area and becomes active when the temperatures warm. WNV has been actively transmitted through bird and mosquito populations every summer in San Joaquin County since 2004. Humans (and horses) can become infected with WNV when bitten by an infected mosquito.

As temperatures rise and more people spend time outdoors this holiday weekend, now is the time to start protecting yourself and your family from mosquito bites:

• Dump and drain standing water around your yard, including plant saucers, buckets, toys, and other containers.
• Apply an EPA-registered insect repellent when spending time outdoors.
• Wear loose-fitting, layered clothing with long sleeves and pants when possible.
• Horses can be protected with a WNV vaccine (no vaccine is available for humans).

Enjoy the outdoors safely and help reduce mosquito breeding around your home!

The first mosquito sample of the season in our District has tested positive for West Nile virus.

West Nile virus is spread through the bite of an infected mosquito, which is why prevention is especially important as mosquito activity increases during warmer weather. Using repellent, dumping standing water, and avoiding mosquito bites can help protect you and your family.
Learn more via the graphic below and here- https://bit.ly/WestNileFirstSamplePositive

In observance of Memorial Day, our office will be closed on Monday, May 25.

As you enjoy the outdoors this holiday weekend, don’t forget to protect yourself and your family from mosquitoes:

• Dump & drain standing water hidden in plant pots, toys, buckets, and other containers
• Use an EPA-registered insect repellent
• Wear loose layered clothing with long sleeves and pants

Wishing everyone a safe Memorial Day weekend!

🩸🦟 Help save lives and “starve a mosquito” at our upcoming community blood drive!

In recognition of National Mosquito Control Awareness Week (June 21-27, 2026), the San Joaquin County Mosquito & Vector Control District has partnered with the American Red Cross to support a critical community need while raising awareness about one of nature’s most persistent blood-feeding insects — mosquitoes!

Starve a Mosquito! Blood Drive
📍 Robert Cabral Ag Center
2101 E. Earhart Ave., Stockton, CA 95206
🗓 Thursday, June 25, 2026
⏰ 10:00 a.m. – 4:00 p.m.

✅ Register today:
https://www.redcrossblood.org/give.html/drive-results?zipSponsor=SJmosquito

Unable to donate blood? You can still help by sharing our posts and following our page for mosquito prevention tips and information on how to help keep our communities safe from mosquito-borne diseases!

Kids can make great mosquito detectives! 🕵️🦟

These sharp-eyed youngsters spotted a hidden mosquito source, water collecting inside an old playground slide that was full of mosquito larvae. With help from an adult, they tipped out the water and helped stop mosquitoes before they could grow into biting adults.

Thank you for doing your part to help protect the community! 👏

Remember: mosquitoes can grow in even small amounts of standing water. Check your yard weekly for anything that can collect water, then tip or toss it to help prevent mosquitoes.

🔎💧Spot the source. Stop the swarm!🚫🦟