The Santa Clara County Vector Control District will conduct aerial spraying over the Palo Alto flood basin this Thursday to reduce the population of aggressive mosquitoes known to travel up to 20 miles in search of a blood meal.

Officials say recent rains have created mosquito breeding grounds in the marsh that cannot be reached by foot, making this treatment necessary to prevent adult mosquitoes from emerging. These winter salt marsh mosquitoes (Aedes squamiger) are known for their persistent biting behavior and ability to spread into surrounding communities.

The operation, starting at 7:30 a.m., will use a helicopter to apply naturally occurring microbes and a hormone regulator to prevent mosquito larvae from maturing. According to Vector Control District Manager Dr. Nayer Zahiri, this method is effective and environmentally safe, posing no risk to beneficial insects, wildlife, or humans.

During the spraying, trails surrounding the flood basin will be closed for public safety but will reopen once the operation is complete.

What This Means for Los Angeles County

While this operation targets mosquitoes in Palo Alto, similar aggressive species exist in Los Angeles County, including Aedes aegypti and Aedes albopictus, both of which are known to travel long distances and bite aggressively during the day. These mosquitoes can spread diseases like dengue, Zika, and chikungunya, making mosquito control a priority in local communities.

To prevent mosquito breeding in your area, eliminate standing water, report unmaintained pools, and use EPA-approved insect repellents.