Texas Mosquito Control Response Following Hurricane Harvey

Area of Science:

• Environmental Science
• Entomology
• Public Health

Background:

• Hurricane Harvey caused unprecedented flooding in Texas.
• This necessitated the largest aerial mosquito control operation in U.S. history.
• Mosquito-borne disease risk increased due to widespread flooding.

Purpose of the Study:

• To evaluate the effectiveness of aerial insecticide applications for mosquito control post-Hurricane Harvey.
• To identify the primary mosquito species targeted and their population reduction.
• To assess the impact of large-scale mosquito abatement efforts on public health.

Main Methods:

• Aerial spraying of Dibrom (naled) and Duet (prallethrin and sumithrin) across 6.7 million acres.
• Mosquito surveillance conducted by contractors and county agencies pre- and post-application.
• Identification and quantification of mosquito species collected.

Main Results:

• Dibrom achieved 93-95% control of key mosquito species, including Psorophora columbiae and Culex nigripalpus.
• Duet showed lower efficacy, with 49-69% control of Psorophora columbiae.
• Psorophora columbiae was the dominant nuisance mosquito, while Culex nigripalpus was the most abundant vector.

Conclusions:

• Aerial application of Dibrom was highly effective in reducing nuisance and vector mosquito populations after Hurricane Harvey.
• Duet demonstrated moderate effectiveness against floodwater mosquitoes.
• These findings support the critical role of aerial insecticide application in managing mosquito populations during large-scale disaster events.