Invasive Aedes Mosquitoes
What are Aedes aegypti Mosquitoes?
Invasive Aedes aegypti mosquitoes are small, black-and-white, aggressive daytime biters that can transmit diseases such as Zika, dengue, chikungunya and yellow fever.
- Develop in small containers of standing water
- Thrive in urban and residential areas
- Eggs can survive dry conditions for months
How to Protect Yourself
- Use EPA-registered insect repellent
- Wear long sleeves and pants when outdoors
- Eliminate standing water around your home
- Report daytime mosquito activity to the District
- Remove potential Aedes development sites from your home by identifying and eliminating common water sources:
- Drain flower pots and plant saucers
- Fill tree holes and bamboo stumps
- Remove unused tires, buckets, and cans
- Refresh pet water bowls regularly
- Keep rain barrels covered
- Clean out gutters and bird baths
- Stock ponds with mosquitofish
- Maintain ornamental fountains
District Response to Aedes Detections
The Placer Mosquito and Vector Control District is actively responding to Aedes mosquito detections through its invasive mosquito response plan, which includes:
- Door-to-door outreach.
- Property inspections of front and back yards.
- Traps to monitor mosquito populations.
- Localized larvicide and, if necessary, adulticide treatments to reduce all life stages of the mosquito.
Invasive Aedes Mosquito Detections
2025 Detections
- Updated June 5, 2025 – Detected in Theiles Manor and Foothills Junction neighborhoods of Roseville, Old Rocklin and Sunset Whitney neighborhoods of Rocklin and the Downtown and North Central neighborhoods of Lincoln.
Detection History by Year
- 2019 – First detection in South Placer County
- 2020–2021 – No detections reported
- 2022 – Found in Granite Bay and Roseville
- 2023 – Established in Cherry Glen, Hillcrest, Cresthaven, Theiles Manor
- 2024 – Expanded to more areas in Roseville, plus Rocklin, Lincoln, and Granite Bay
The District continues to monitor the county for invasive Aedes mosquitoes through active surveillance and neighborhood property inspections.
Map Legend:
- Green Shaded Areas: Locations where invasive Aedes aegypti mosquitoes have been detected in 2025.
- Yellow Shaded Areas: Locations where Aedes aegypti mosquitoes were detected in 2024.
- Orange Shaded Areas: Locations where Aedes aegypti mosquitoes were detected in 2023.
Where Invasive Aedes Hide
Invasive Aedes aegypti mosquitoes are known to breed in small, hidden water sources around your home. They can lay eggs in cryptic spots like:
- Plant saucers
- Yard drains
- Discarded tires
- Pet water bowls
- Clogged gutters
These mosquitoes only need small amounts of standing water to lay their eggs. To help reduce the spread, inspect your property regularly and eliminate all standing water. This is a key step to making your home Aedes-free and reducing mosquito breeding sites.
