When we spoke to Kevin Sexton, director of Jefferson County Mosquito Control, Texas was in the midst of a West Nile virus outbreak that had already caused deaths in the double digits. He had been on and off the phone, “checking in” with the Health Department; and fortunately, while Jefferson County collected positive pools from four separate locations, no human cases had been reported to date in its treatment area of Beaumont, TX.

Jefferson County is located on the Gulf coast, on the border of Louisiana, 90 miles east of Houston. One side of the 1,110-square-mile county deals primary with salt marsh mosquitoes as its primary nuisance vector, while the other side deals with rice field mosquitoes. Jefferson County is the largest of its neighboring counties, employing 14 full-time employees plus 11 seasonal employees. The county’s typical mosquito control regimen is powered by three aircrafts, including a twin-engine King Air it uses as needed during bad outbreaks, like the current West Nile virus outbreak. Its ground spray efforts consist of eight trucks that apply alternating adulticide products, after resistance testing proved the method to be most effective in lessening the resistance of target mosquitoes.

Sexton says the county’s salt marsh and rice field mosquitoes are out at all times of the day, so aerial and ground spray efforts generally take place both in the morning and evening. The treatment plan to attack the current West Nile virus activity, however, requires a bit of a different approach in those positive pool areas. The target mosquitoes are active in the evening, from dusk until dawn. The county can only be effective spraying as late as possible in the evening, but also when it’s still safe for the planes to fly. Therefore, the King Air takes off just before sundown for a 45-minute trip and lands just before dark. In addition, the trucks set off around dusk and spend about four evening hours spraying.

Jefferson County depends heavily on the truck fleet right now, with help from the King Air. Of the county’s eight trucks, six are modified with dual steering for its daytime larvicide program, which targets disease-carrying mosquitoes by spraying catch basins and storm drains, attempting to kill the larvae. For this effort, Sexton’s team uses Agnique products provided by ADAPCO®.

When asked if the current threat of West Nile virus makes things more active for his team, Sexton replied, “As long as we have mosquitoes present, based on landing rates and light traps, the trucks are out on a regular basis as well as our King Air. So, it’s the same amount of work; the threat of West Nile virus just adds a little more pressure to the situation.”

West Nile virus is not only on the minds of the Jefferson County Mosquito Control team. “Media are at our door step a lot; the big story is West Nile virus, and they’re interested in our methods.” The attention is positive from Sexton’s perspective, “Through the news media, we’ve been able to educate the public on what they can do to help themselves, and to help us help them.”

Note: A week after we spoke to Sexton, Port Arthur News reported the first human case of West Nile virus confirmed in Beaumont, TX. Based on the high level of West Nile virus activity in surrounding areas, Jefferson County Mosquito Control has performed exceptionally in taking proactive measures to protect the public as best as possible from mosquito-borne diseases.


(Photographer credit: Morgan Jones of Port Arthur News)