Presented by Jamie Mangan at the 92nd Annual American Mosquito Control Association (AMCA) Conference in Portland, OR.

Abstract:

In January 2025, wildfires in Los Angeles County, California, spread into residential areas and caused unprecedented destruction. The Eaton Fire destroyed thousands of homes in the San Gabriel Valley. The San Gabriel Valley Mosquito and Vector Control District (SGVMVCD) responded to the area, with particular focus on the thousands of damaged, unmaintained swimming pools. Existing surveillance sites and control practices allowed for an effective response to a rapidly evolving emergency.

Historical gravid trap surveillance sites were monitored weekly in addition to new sites in varying proximity to the burn area. Trapping was later supplemented by BG Sentinels and emergence traps placed in pools. Surveillance coincided with the individual treatment of thousands of swimming pools with multiple long residual products and Gambusia mosquito fish.

Abundance of the primary local West Nile virus (WNV) vector, Culex quinquefasciatus, was monitored weekly and compared with historical data. While Cx. quinquefasciatus abundance stayed within the expected range, other WNV vector species increased in abundance. Emergence traps and CO2-baited BG Sentinels reflected the shift in abundance and distribution of several Culex, Anopheles, and Aedes species.

The results of the SGVMVCD response to the Eaton Fire demonstrate how historical data and established control practices can be adapted in response to an emergency that is not the typical flood-related mosquito emergency. The impacts of the Eaton Fire will last for years, requiring continued adaptation of vector control practices.

Resources: 

Do you have a question for me or want to get in contact with me?