Aedes Aegypti: How You Can Help Combat Invasive Mosquitoes

SANTA CLARA, CALIF. — Winter has arrived, but the threat of mosquitoes hasn't vanished.

There are important things you can do to protect yourself and your community from an invasive species of mosquito known as Aedes aegypti. The day-biting mosquito is capable of transmitting diseases such as Zika and dengue that do not typically occur in the United States. 

Mosquitoes generally disappear when temperatures get cold, but Aedes aegypti can remain active in the winter if daytime temperatures reach 60 degrees or so.

These mosquitoes are “container breeders,” preferring to lay their eggs just above the water line in small, artificial sources of water such as buckets, pet dishes, fountains and bird baths, plant pots and saucers, and old tires. Once laid, the eggs can last for more than a year without water.

The invasive insect has been detected in six locations in Santa Clara County in 2024. Here's what you can do to help prevent it from establishing a permanent population:

• After it rains, dump the water out of any outdoor containers such as dog dishes or plant saucers and clean them by scrubbing them with hot, soapy water or undiluted bleach.
• Report day-biting mosquitoes immediately to the County of Santa Clara Vector Control District at (408) 918-4770 or [email protected].
• If you live in an area where the day-biting mosquito has been detected, allow district staff to access your property to check for mosquitoes and treat them as needed. 

Working together, the Vector Control District, residents and businesses can stop this unwanted guest from finding a new home in Santa Clara County.

To learn more about Aedes aegypti and what the County is doing to get rid of it, visit the Vector Control District's invasive mosquitoes webpage.