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An improved autocidal gravid ovitrap for the control and surveillance of Aedes aegypti.

Mackay AJ, Amador M, Barrera R - Parasit Vectors (2013)

Bottom Line: We had developed an autocidal gravid ovitrap (AGO) as a simple, low-cost device for surveillance and control of Ae. aegypti without the use of pesticides that does not require servicing for an extended period of time.Semi-weekly collections of Ae. aegypti females in the AGO-B were significantly correlated with cumulative rainfall 8 to 28 days prior to sampling, whereas egg collections in paired conventional ovitraps were not.When vector abundance was low, the AGO-B provided greater sensitivity and precision as a surveillance device, compared with paired conventional ovitraps.

View Article: PubMed Central - HTML - PubMed

Affiliation: Entomology and Ecology Activity, Dengue Branch, Centers for Disease Control and Prevention, 1324 Calle Cañada, San Juan, Puerto Rico. amackay@illinois.edu

ABSTRACT

Background: Limited success has been achieved using traditional vector control methods to prevent the transmission of dengue viruses. Integrated control programs incorporating alternative tools, such as gravid ovitraps (lethal ovitraps and sticky ovitraps) may provide greater potential for monitoring and reducing vector populations and dengue virus transmission. We had developed an autocidal gravid ovitrap (AGO) as a simple, low-cost device for surveillance and control of Ae. aegypti without the use of pesticides that does not require servicing for an extended period of time. The purpose of our study was to improve the efficacy and efficiency of this device.

Methods: Competitive assays were performed in the laboratory and an outdoor cage to evaluate whether modifications to the structure and appearance of our original trap design (AGO-A), and the addition of an olfactory bait (hay infusion), improve trap function. The performance of a modified trap design (AGO-B) was then assessed and compared with conventional ovitraps in a series of field tests in San Juan City, Puerto Rico. Generalized linear mixed models were used to analyze adult Ae. aegypti capture data from the laboratory, outdoor cage and field experiments.

Results: Increasing the size of the trap entrance, altering the color of trap components, and increasing the volume/surface area of the aqueous bait significantly improved the performance of the AGO in the outdoor cage. In a subsequent field comparison, captures of Ae. aegypti females were 3.7 fold greater in the improved trap (AGO-B), compared with the original design (AGO-A). An infusion bait produced "in situ" significantly improved capture rates of the improved trap under both semi-natural and field conditions. Semi-weekly collections of Ae. aegypti females in the AGO-B were significantly correlated with cumulative rainfall 8 to 28 days prior to sampling, whereas egg collections in paired conventional ovitraps were not. When vector abundance was low, the AGO-B provided greater sensitivity and precision as a surveillance device, compared with paired conventional ovitraps.

Conclusions: The AGO-B can be used to efficiently attract and capture gravid Ae. aegypti females for more than 8 weeks without the need for trap maintenance.

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Related in: MedlinePlus

The improved autocidal gravid ovitrap (AGO-B). Components include a 19 l black pail (a), a black pail lid (b), a 12.8 cm entrance diameter (c), a black capture surface (CS) coated with adhesive (d), PAM (e), a 9.3 l capacity infusion reservoir (f), and a screen barrier between the CS and the infusion reservoir (g). A conventional ovitrap is visible in the foreground of the photograph, on the right-hand side of the AGO-B.
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Figure 2: The improved autocidal gravid ovitrap (AGO-B). Components include a 19 l black pail (a), a black pail lid (b), a 12.8 cm entrance diameter (c), a black capture surface (CS) coated with adhesive (d), PAM (e), a 9.3 l capacity infusion reservoir (f), and a screen barrier between the CS and the infusion reservoir (g). A conventional ovitrap is visible in the foreground of the photograph, on the right-hand side of the AGO-B.

Mentions: The AGO-B (Figure 2) was constructed similar to the AGO-A, except for the following changes. The color of the pail lid was changed from white to black. To form the capture chamber, the 3.8 l black, polyethylene bucket was inverted and raised so that it transected the pail lid. A 12.8 cm diameter hole was cut in the apex of the capture chamber to create the trap entrance. The color of the adhesive-coated CS lining the capture chamber was changed from white to black. The infusion attractant was added directly to the pail to a maximum volume of 9.3 l. The trap entrance was covered by ¾” black polypropylene, oriented netting (Industrial Netting, Minneapolis, Minnesota, USA) to exclude the entry of larger debris or organisms.


An improved autocidal gravid ovitrap for the control and surveillance of Aedes aegypti.

Mackay AJ, Amador M, Barrera R - Parasit Vectors (2013)

The improved autocidal gravid ovitrap (AGO-B). Components include a 19 l black pail (a), a black pail lid (b), a 12.8 cm entrance diameter (c), a black capture surface (CS) coated with adhesive (d), PAM (e), a 9.3 l capacity infusion reservoir (f), and a screen barrier between the CS and the infusion reservoir (g). A conventional ovitrap is visible in the foreground of the photograph, on the right-hand side of the AGO-B.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3750875&req=5

Figure 2: The improved autocidal gravid ovitrap (AGO-B). Components include a 19 l black pail (a), a black pail lid (b), a 12.8 cm entrance diameter (c), a black capture surface (CS) coated with adhesive (d), PAM (e), a 9.3 l capacity infusion reservoir (f), and a screen barrier between the CS and the infusion reservoir (g). A conventional ovitrap is visible in the foreground of the photograph, on the right-hand side of the AGO-B.
Mentions: The AGO-B (Figure 2) was constructed similar to the AGO-A, except for the following changes. The color of the pail lid was changed from white to black. To form the capture chamber, the 3.8 l black, polyethylene bucket was inverted and raised so that it transected the pail lid. A 12.8 cm diameter hole was cut in the apex of the capture chamber to create the trap entrance. The color of the adhesive-coated CS lining the capture chamber was changed from white to black. The infusion attractant was added directly to the pail to a maximum volume of 9.3 l. The trap entrance was covered by ¾” black polypropylene, oriented netting (Industrial Netting, Minneapolis, Minnesota, USA) to exclude the entry of larger debris or organisms.

Bottom Line: We had developed an autocidal gravid ovitrap (AGO) as a simple, low-cost device for surveillance and control of Ae. aegypti without the use of pesticides that does not require servicing for an extended period of time.Semi-weekly collections of Ae. aegypti females in the AGO-B were significantly correlated with cumulative rainfall 8 to 28 days prior to sampling, whereas egg collections in paired conventional ovitraps were not.When vector abundance was low, the AGO-B provided greater sensitivity and precision as a surveillance device, compared with paired conventional ovitraps.

View Article: PubMed Central - HTML - PubMed

Affiliation: Entomology and Ecology Activity, Dengue Branch, Centers for Disease Control and Prevention, 1324 Calle Cañada, San Juan, Puerto Rico. amackay@illinois.edu

ABSTRACT

Background: Limited success has been achieved using traditional vector control methods to prevent the transmission of dengue viruses. Integrated control programs incorporating alternative tools, such as gravid ovitraps (lethal ovitraps and sticky ovitraps) may provide greater potential for monitoring and reducing vector populations and dengue virus transmission. We had developed an autocidal gravid ovitrap (AGO) as a simple, low-cost device for surveillance and control of Ae. aegypti without the use of pesticides that does not require servicing for an extended period of time. The purpose of our study was to improve the efficacy and efficiency of this device.

Methods: Competitive assays were performed in the laboratory and an outdoor cage to evaluate whether modifications to the structure and appearance of our original trap design (AGO-A), and the addition of an olfactory bait (hay infusion), improve trap function. The performance of a modified trap design (AGO-B) was then assessed and compared with conventional ovitraps in a series of field tests in San Juan City, Puerto Rico. Generalized linear mixed models were used to analyze adult Ae. aegypti capture data from the laboratory, outdoor cage and field experiments.

Results: Increasing the size of the trap entrance, altering the color of trap components, and increasing the volume/surface area of the aqueous bait significantly improved the performance of the AGO in the outdoor cage. In a subsequent field comparison, captures of Ae. aegypti females were 3.7 fold greater in the improved trap (AGO-B), compared with the original design (AGO-A). An infusion bait produced "in situ" significantly improved capture rates of the improved trap under both semi-natural and field conditions. Semi-weekly collections of Ae. aegypti females in the AGO-B were significantly correlated with cumulative rainfall 8 to 28 days prior to sampling, whereas egg collections in paired conventional ovitraps were not. When vector abundance was low, the AGO-B provided greater sensitivity and precision as a surveillance device, compared with paired conventional ovitraps.

Conclusions: The AGO-B can be used to efficiently attract and capture gravid Ae. aegypti females for more than 8 weeks without the need for trap maintenance.

Show MeSH
Related in: MedlinePlus