San Joaquin County Mosquito & Vector Control District

07/30/2026

Noticing mosquitoes in your neighborhood?

Did you know: even a tablespoon of water can produce mosquitoes! From neglected pools to bottle caps and plant saucers collecting water, mosquitoes can use any of these water sources to grow!

Take a few minutes 𝐞𝐯𝐞𝐫𝐲 𝐰𝐞𝐞𝐤 to:
🔍 Inspect your yard for hidden mosquito sources
🪣 Dump and drain standing water
🪴 Tip and toss containers that can collect water
🪟 Screen yard drains with 1/16" fine-mesh window screen under the cap
🧴 Use EPA-registered mosquito repellent

Spot the Source. Stop the Swarm! 🚫🦟

07/30/2026

🐴 Protect your horse from West Nile virus

Horses can become infected with West Nile virus through the bite of an infected mosquito. Help reduce the risk by taking steps to prevent mosquitoes around your property:

✔️ Use veterinarian-approved mosquito protection for horses when appropriate.
✔️ Talk to your veterinarian about West Nile virus prevention options, including vaccination.
✔️ Eliminate standing water around your property to prevent mosquito development
✔️ For permanent water sources, such as horse watering troughs, use mosquitofish to help prevent mosquitoes from developing in that source. Free mosquitofish are available from the San Joaquin County Mosquito & Vector Control District.

While a vaccine is available for horses, there is currently no vaccine for people. Preventing mosquito bites remains the best way to protect yourself and your family.

Learn more or request free mosquitofish at
www.sjmosquito.org.

07/29/2026

🦟 West Nile Virus Update

West Nile virus activity continues to expand throughout San Joaquin County as mosquito surveillance remains underway throughout the summer.

📍 This updated map (as of July 29, 2026) shows where the San Joaquin County Mosquito & Vector Control District has detected West Nile virus activity so far in 2026*:
• City of Escalon (new)
• Clements (new)
• Delta Islands
• Rural Escalon
• Stockton
• South Manteca
• Tracy

*The map legend identifies what type of sample the West Nile virus detections were made in: Cx. pipiens (Northern house mosquito), Cx. tarsalis (Western encephalitis mosquito), or a dead bird.

District staff monitor mosquito populations by trapping mosquitoes and testing both mosquitoes and dead birds each week for West Nile virus. These surveillance efforts provide an early warning of virus activity, allowing the District to respond with targeted mosquito control measures in areas with increased disease transmission risk.

With hot summer temperatures continuing, West Nile virus activity is expected to increase further in the coming weeks. Help protect yourself and your family from mosquito bites:

✅ Apply an EPA-registered insect repellent before spending time outdoors.
✅ Wear loose-fitting, layered clothing with long sleeves and long pants when mosquitoes are most active.
✅ Inspect your yard every week and dump or drain any standing water where mosquitoes develop.

💻 Learn more about West Nile virus or sign up for news and spray alerts at www.sjmosquito.org.



City of Escalon

07/29/2026

🦟 What does summer heat mean for mosquitoes and the diseases they can spread?

Our District Public Information Officer recently spoke to ABC10's Monica Woods about mosquitoes in California, how warmer weather affects mosquito activity and mosquito-borne disease transmission, and—most importantly—what residents can do to help reduce mosquitoes around their homes.

While California has over 50 different mosquito species (including 18 found here in San Joaquin County), they all have one thing in common: every mosquito starts its life in standing water.

That's why taking a few minutes each week to inspect your yard for standing water can make a BIG difference within your neighborhood.

✅ Inspect your yard weekly and look for hidden sources
✅ Dump and drain standing water, even as little as a bottlecap's worth!
✅ Request mosquitofish for permanent water features

Spot the source. Stop the swarm!

For more mosquito prevention tips, visit sjmosquito.org.

https://www.abc10.com/video/news/health/several-california-cities-top-the-list-of-mosquito-activity/103-51be0624-83e3-4b75-9bcf-d83892968016

New research shows San Francisco, Salinas and Santa Maria lead the nation in rising days favorable for mosquito-borne disease activity.

07/29/2026

🦟 Many people think mosquito control is just about spraying.
In reality, the most effective mosquito control starts long before adult mosquitoes are flying.

Mosquitoes can develop in as little as a bottlecap of standing water, which means the most important place to reduce mosquitoes is right in our own backyards.

At the District, we work year-round to protect public health through mosquito surveillance, source reduction, biological control, larval treatments, and targeted adult mosquito control. But effectively reducing neighborhood mosquitoes long-term takes all of us.

✔️ Check your yard every week for hidden water.
✔️ Dump and drain all standing water, even as little as a bottlecap!
✔️ Encourage your neighbors to do the same.

When an entire neighborhood helps eliminate mosquito breeding sources, it makes a BIG difference!

🔎💧Spot the source. Stop the swarm! 🚫🦟

Visit our website for more mosquito prevention tips: https://www.sjmosquito.org/Mosquitoes-Ticks/Mosquito-Prevention-Tips

07/27/2026

🦟 It doesn't take much water for mosquitoes to become a problem!

In fact, the invasive species (Aedes aegypti) now in most San Joaquin County neighborhoods can develop in as little as a bottlecap of standing water!

That's why one of the most effective ways to reduce mosquitoes around your home is to inspect your yard every week for anything holding water. Even small, overlooked items can become mosquito breeding sites.

💧 Dump and drain standing water from sources like:
• Plant saucers
• Buckets
• Toys
• Tarps
• Pet water bowls
• Clogged gutters
• Wheelbarrows
• Yard drains (screen to prevent mosquitoes)

For permanent sources like ponds, fountains, and livestock water troughs, request your free mosquito-eating fish from the District.

Working together, we can help reduce mosquitoes in our neighborhoods and protect our community.

🔎💧 Spot the source. Stop the swarm! 🚫🦟

Visit our website for more mosquito prevention tips: https://www.sjmosquito.org/Mosquitoes-Ticks/Mosquito-Prevention-Tips

07/23/2026

🦟 West Nile Virus Update

West Nile virus activity continues to increase in San Joaquin County as mosquito surveillance remains underway throughout the summer.

📍 This updated map (as of July 22, 2026) shows where the SJC Mosquito & Vector Control District has detected West Nile virus activity so far in 2026*:
• Delta Islands
• Stockton
• South Manteca
• Rural Escalon
• Tracy (new)

*The map legend identifies what type of sample the West Nile virus detections were made in: Cx. pipiens (Northern house mosquito), Cx. tarsalis (Western encephalitis mosquito), or dead bird.

District staff monitor mosquito populations by trapping mosquitoes and testing both mosquitoes and dead birds each week for West Nile virus. These surveillance efforts provide an early warning of virus activity, allowing the District to respond with targeted mosquito control measures in areas with disease transmission risk.

With hot summer temperatures continuing, West Nile virus activity is expected to continue. It is important to take steps to protect yourself and your family from mosquito bites:

✅ Apply an EPA-registered insect repellent before spending time outdoors.
✅ Wear loose-fitting, layered clothing with long-sleeved shirts and long pants when mosquitoes are most active.
✅ Inspect your yard every week and dump or drain any standing water which is where mosquitoes develop.

💻 Learn more about West Nile virus or sign up for news and spray alerts at
www.sjmosquito.org.



City of Tracy - Local Government City of Stockton - Government City of Manteca - Local Government City of Escalon

07/23/2026

Thank you to the Stockton Sunrise Rotary for inviting the San Joaquin County Mosquito & Vector Control District as your guest speaker this week!

We enjoyed sharing how our District monitors and reduces mosquitoes, protects public health through science-based mosquito control, and how residents can help prevent mosquitoes in their own neighborhoods. Thank you for the opportunity to connect with your members!

🦟 Interested in having the District present to your community group, school, or neighborhood association? Request a free presentation at www.sjmosquito.org

07/20/2026

🦟 You may see District Mosquito Control staff in your neighborhood

During the summer months, San Joaquin County Mosquito & Vector Control District staff treat public neighborhood mosquito breeding sources such as storm drains, catch basins, and utility vaults holding water, to prevent mosquito larvae from growing into adult mosquitoes.

Staff are also conducting door-to-door yard inspections in areas with high numbers of the invasive mosquito (Aedes aegypti) to help identify and eliminate its breeding sources which are hidden in residential yards.

📍 Current inspection areas:
• Manteca
• Stockton
• Tracy

Our technicians wear tan and green District uniforms with the District logo and carry a District-issued photo identification badge. They may also leave a door hanger if you're not home.

We appreciate your cooperation by allowing our staff to inspect for mosquito breeding sources around your property.

💧 You can help, too. Inspect your yard every week and remove standing water and unnecessary containers around your home. The invasive Aedes aegypti mosquito can develop in as little as a bottlecap of water and grows in hidden water sources throughout residential yards.

This invasive species cannot be controlled long-term by spraying individual homes. As long as the water sources remain, adults will continue to emerge even after a spray treatment. The most effective way to reduce these mosquitoes is to find and eliminate the water sources where they're growing, before they become flying, biting adults.

The best mosquito control starts before mosquitoes can fly. Together, we can stop them at the source.

🔎💧SPOT the source. STOP the swarm! 🚫🦟



City of Manteca - Local Government City of Stockton - Government City of Tracy - Local Government

07/16/2026

The San Joaquin County Mosquito & Vector Control District Board of Trustees has voted to not increase the District's benefit assessment rates for the 2026–27 fiscal year. The decision reflects the District's commitment to finding innovative efficiencies and cost-saving measures while continuing to provide while continuing to provide essential mosquito and vector control services, disease surveillance, and prevention programs throughout San Joaquin County.

Read the full news release here: https://bit.ly/NewsReleasesSJCMVCD