Fort Bend County Health & Human Services reported an 83% reduction in mosquito activity following a recent aerial mosquito-control operation. The agency released surveillance data showing the operation impacted populations across the county after environmental conditions favored breeding.

Mosquito surveillance trap counts dropped from 109,536 before treatment to 18,711 after treatment, according to Fort Bend County Health & Human Services. The aerial spraying was conducted after heavy rainfall and flooding created ideal breeding conditions for mosquitoes.

Twelve of the county’s 15 targeted treatment areas experienced mosquito population reductions of more than 75%. One treatment area recorded an increase in mosquito activity and is undergoing additional surveillance.

"These results demonstrate that our aerial mosquito control operation was highly effective in rapidly reducing mosquito populations across the targeted areas," said Dr. Letosha Gale-Lowe, local health authority and director of Fort Bend County Health & Human Services. County officials stated that reducing mosquito populations is an important step in lowering the risk of West Nile virus, but cautioned that no single treatment can eliminate the threat.

West Nile virus is maintained through a natural cycle between mosquitoes and birds, allowing it to persist or return as environmental conditions change. Officials stated that mosquito populations can rebound after rainfall as new mosquitoes emerge or move in from untreated areas.

Fort Bend County stated it will continue using an Integrated Pest Management approach that includes year-round mosquito surveillance, laboratory testing, larval mosquito control, targeted adult mosquito control, and public education. Surveillance will continue throughout mosquito season, and additional control measures will be implemented if needed.

Health officials encourage residents to follow the 4 Ds of mosquito prevention: limit outdoor activities at Dusk and Dawn, Drain standing water, Dress in long sleeves and pants, and Defend using EPA-approved insect repellent. Recommended EPA-approved insect repellents include those containing DEET, picaridin, or oil of lemon eucalyptus.

Residents can help reduce mosquito breeding by maintaining swimming pools, cleaning gutters, changing birdbath water regularly, and ensuring doors and windows have properly fitting screens. These individual actions complement the county's broader efforts to manage vector-borne disease risks through coordinated surveillance and control.