Northern Nevada Public Health suspends helicopter spraying, will rely on targeted drone treatments and surveillance

Northern Nevada Public Health announced that it will suspend large-area helicopter spraying for mosquito control during the 2025 season and will instead rely on continued surveillance, targeted treatments (including drone applications) and community education.

Dr. Chad Kegsley, district health officer for Northern Nevada Public Health, told the Sparks City Council the decision was driven by rising contractor and product costs and by a low incidence of locally acquired mosquito-borne disease in recent years.

“We are suspending a large area treatment for this season, and that is the flying of the helicopter. We will continue surveillance and hand drone treatments,” Kegsley told council. He said the department operates its own drone for limited-capacity, targeted treatments in areas inaccessible by ground crews.

Kegsley said the helicopter contractor cost was approximately $46,000 and that staff had already spent about $19,000 in the previous fiscal period; he noted that the price of the primary larvicide has risen from roughly 12.5% to about 17% (as measured by concentration/cost indicators cited by staff) since early 2021 and that helicopter costs have increased roughly 20% year over year. For those reasons, staff concluded the large-area aerial application was not fiscally sustainable under the current budget without cutting mandated services.

The district will continue to operate trap-based surveillance, laboratory testing of mosquito pools and focused ground-based larvicide application where monitoring indicates elevated mosquito numbers. Kegsley said staff will respond to public requests for service and asked residents to call 311 so the department can capture addresses and exposure details.

Council members thanked staff for the outreach and asked about the budget and community education plans. Kegsley said the program will include social media outreach, partnerships with local jurisdictions, and targeted messaging about eliminating standing water and personal protective measures during dusk and dawn hours.

He also said that over the last five years the department had one locally acquired case of West Nile virus (2023) and that dengue and malaria cases diagnosed locally were travel-related (imported) illnesses; the Aedes aegypti mosquito species that can transmit dengue and malaria has not been identified in the district, he said.

What remains in 2025: routine surveillance, targeted drone and ground treatment where warranted, complaint response and investigation of any vector-borne disease reports. The department will hire two interns to help during the season and will continue to coordinate with local partners and media for public education and outreach.