On Aug. 26, 2025, health officials in Ashland, Oregon reported that six Aedes aegypti mosquitoes were found in two traps—marking the first detection in 2025.

Aedes aegypti is a non-native mosquito species that was first detected in Oregon in 2024. It is known for its aggressive daytime biting and its ability to transmit diseases such as dengue, chikungunya, yellow fever, and Zika. While the current disease risk remains low, the potential for long-term establishment is a serious concern.

The Aedes aegypti  prefers to bite humans, especially during daylight hours and can breeds in very small amounts of water—just a bottle cap’s worth. It can survive indoors and outdoors, making residential areas ideal habitats, and the end Eggs can remain viable for months, even in dry conditions.