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There are over 60 species of mosquitoes in North Carolina. An understanding of the biology of the mosquito species in your county will improve the targeting effort. This is the first step towards
developing an operational mosquito control strategy. Mosquito biology considerations, as they relate to ULV applications, include flight times for each species, distance each species is known to fly,
habitat preference and seasonal distribution. If needed, Public Health Pest Management personnel can help you identify the mosquito species in your community. Locating and prioritizing treatment areas
prior to adulticiding is essential for the success of the operation.
To determine the treatment area, a map with the jurisdictional boundaries of your program is required. Identify the populated areas to be controlled within your boundaries. Draw a box around these areas.
Next, following the roadways, plot a treatment route that goes from one end of the zone to the other in a methodical manner, being sure to cover all the roads. For dead end roads, the operational rule is
to drive to the end of the road and spray your way out. Do this for all the roads in each treatment area that have been identified on the operational map. Calculate the total area to be treated within
each protected zone to determine the number of linear miles of roadway within the protected areas. A simple way to do this is to drive each route and use the vehicle’s odometer reading.
When all the protected areas in your county have been identified on a map, they can be prioritized by the amount of mosquito production and the level of service required in each area. A good way to verify
mosquito production and the level of service required in each area is by reviewing any historical records and by ground truthing each area. Ground truthing involves identifying potential mosquito
habitats and evaluating whether they will affect the human population residing in each protected area.
The operational period for targeted ULV applications is 21 consecutive days from the date of adult emergence. Larval dipping is the key to pinpointing adult emergence. Onelimiting factor restricting
ground ULV operations is the number of operational ULV’s. Each ULV requires a truck and an operator. Locating and training personnel to operate ULV’s prior to an emergency response is critical. Each
State assisted program should have someone certified in Public Health Pest Control. Support personnel are allowed to work under the direct supervision of the licensed operator if the person holding the
license agrees. Ultimately, it is the license holder that accepts the responsibility for additional personnel. The license holder should feel confident in the abilities of the personnel working under
his/her license. Training and familiarity with the chemical, equipment and areas to be treated is a must.
After inventorying your programs’ assets, the time required to spray the protected area can be calculated. For example, most ULV’s are calibrated to operate at 10 miles per hour. The optimum times for
ULV applications are dawn and dusk for three to four hours each. Trucks can cover 30-40 linear miles during an application. Actual ULV application times will vary depending on weather conditions and
complexity of the route at the time of treatment. Operating one ULV at dawn and dusk for 21 days at 10 mph can treat 1,680 miles and can expend approximately 168 man-hours per machine. Multiply the
number of man-hours by the number of ULV machines to determine the maximum operational capacity of the program.
The best time to project treatment routes is prior to an emergency situation. Predetermined treatment routes facilitate routine applications by allowing adjacent routes to be treated on the same evening
without overlapping or skipping any areas. Spraying large populations of mosquitoes over large areas is more effective if the applications are blanketed across the treatment area. Pre-mapping treatment
areas makes this possible. Some ULV mosquito adulticides are licensed for higher rates of application. In some cases it may be possible to double the application speed by adjusting the flow rate of the
machine. Always refer to the pesticide label for the specific application guidelines. Doubling the application speed will double the area each machine can treat. It also doubles the amount of product
required.
The more ULV’s available, the more comprehensive the response. The operational strategy is to target the control efforts toward each mosquito population affecting the citizens of your county. Mosquito
surveillance data collected from year to year helps to focus and refine the adult control effort. A laminated county map is a good way to track the mosquito hot spots in your jurisdiction. Initially, any
information about mosquito populations can be used. Refine the map regularly to pinpoint the most productive mosquito areas. Treatment routes should be based on providing service to the citizens while
incorporating the mosquito hotspots identified from the surveillance operations. The goal is to minimize human interaction with mosquito populations for the three-week adult mosquito period.
Finally, written records of the treatment history of each protected area will facilitate prioritizing both routine and emergency ULV responses. Treatment histories can help to identify potential mosquito
production sites within the protected area that may be suited for other mosquito control measures like source reduction or larviciding to control mosquito populations. A well-defined plan of action, with
maps of the target areas and current records will enhance routine adulticiding operations or any disaster response
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