Response to An Outbreak of Locally Transmitted Dengue in Key Largo, FL, by The Florida Keys Mosquito Control District.

Dengue virus (DENV) is an ever-increasing threat to the residents of South Florida. Seventy-two cases of locally acquired dengue were contracted by residents and visitors of Key Largo, FL, in 2020. The primary vector, Aedes aegypti, has been a large focus of the Florida Keys Mosquito Control District's (FKMCD) control measures for over a decade. This paper recounts the 2020 outbreak of DENV in Key Largo, FL, and the FKMCD's Ae. aegypti operational response. The overall House Index (13.43%) during the outbreak was considered high (>5%) risk for local transmission. Larval habitat characterized from property inspections was similar to previous larval (τ = 0.78, P < 0.005) and pupal (τ = 0.745, P < 0.005) habitat studies. Adult surveillance of the active dengue transmission area provided 3 positive pools out of 1,518 mosquitoes tested resulting in a minimum infection rate of 1.976. Increased personnel response with long-term larvicide formulations and increased aerial, truck, and handheld ultra-low-volume adulticide control measures quickly reduced the Ae. aegypti surveillance numbers below the action threshold. No active cases of dengue have been reported since October 2020.

Mosquito Surveillance and Insecticide Resistance Monitoring Conducted by the Florida Keys Mosquito Control District, Monroe County, Florida, USA.

Mosquito control programs in the State of Florida are charged with protecting human and animal health, fostering economic development of the State, permitting enjoyment of the natural attractions in Florida, and improving the quality of life of citizens. Mosquito control programs must accomplish these tasks in such a manner as will protect the environment and terrestrial, marine, and freshwater ecosystems. The Florida Keys Mosquito Control District provides a science-based Integrated Pest Management mosquito control program to the residents of the Florida Keys, Monroe County, Florida. Operational decisions are based on surveillance of adult and immature mosquitoes. Mosquito populations are monitored by means of carbon dioxide-baited light traps BG Sentinel traps, truck traps, gravid traps, oviposition traps, and human landing rate counts. Larvae and pupae are monitored by inspections of natural and human-made immature habitats. Due to past and current reliance on chemical pesticides for control of mosquitoes, the District maintains a pesticide resistance detection program consisting of CDC bottle bioassays and larval bioassays, challenging local mosquito species with currently used adulticides and larvicides.

Culex coronator: A New Species Record For Monroe County, Florida.

Reported here are the first documented records of Culex coronator in Monroe County, FL. Adult female specimens were collected over several weeks on multiple islands, indicating that this species is established in all counties of the state of Florida. Global Positioning System coordinates and habitat descriptions are provided.

A Viability Assessment of Two Commercially Available Sticking Adjuvants Added to a Bifenthrin-Based Barrier Treatment on Aedes taeniorhycnhus.

In an effort to reduce Aedes taeniorhynchus numbers in the northernmost community of Key Largo, FL (known as Ocean Reef), during the peak summer months, Florida Keys Mosquito Control District (FKMCD) has utilized a bifenthrin-based barrier application (Wisdom TC Flowable®) for several years. The FKMCD conducted a study comparing whether 2 aftermarket wetting/sticking adjuvants could improve the efficacy of the barrier treatments used to control Ae. taeniorhynchus. Maximum label rate was used for 3 separate solutions: Wisdom TC Flowable (1 fl oz/gal [7.81 ml/liter] water) with no additives (Wisdom), Wisdom with Lesco Spreader-Sticker® (0.08 fl oz [2.37 ml]), and Wisdom with Xtended Performance® (2.56 fl oz [75.71 ml]). All solutions were applied to 100-ft (approximately 3 m) sections of tree-lined roadways in Key Largo, FL, using a SR 420® Mistblower backpack sprayer (Stihl Corp.). Leaves were collected from each application area for 8 consecutive weeks. Leaves were used to perform leaf bioassays against local populations of Ae. taeniorhynchus adults, and mortality was recorded at 1, 4, and 24 h postexposure. This process was replicated 3 times. Treatments had variable mortality rates at 1, 4, and 24 h postexposure across 7 wk following application. Mortality rates for all mixtures decreased for all exposure times throughout the study. Overall, the Lesco Spreader-Sticker solution was the only combination with a positive significant difference in adult mortality after 24 h.