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Journal of Vector Ecology March 2011 S166 Evaluation of propane combustion traps for the collection of Phlebotomus papatasi (Scopoli) in southern Israel Daniel L. Kline1, Günter C. Müller2, and Jerome A. Hogsette1 United States Department of Agriculture-ARS-Center for Medical, Agricultural, and Veterinary Entomology, Gainesville, FL, U.S.A. 2 Department of Microbiology and Molecular Genetics , IMRIC, Kuvin Centre for the Study of Infectious and Tropical Diseases, Faculty of Medicine, Hebrew University, Jerusalem, Israel, 91120 1 ABSTRACT: In this study, we evaluated the efficacy of eleven commercial models of propane combustion traps for catching male and female Phlebotomus papatasi. The traps differed in physical appearance, amount of carbon dioxide produced and released, type and location of capturing device, and the method by which the trap suction fans were powered. The traps tested were the Mosquito Magnet™(MM)-Pro, MM-Liberty, MM-Liberty Plus, MM-Defender, SkeeterVac®(SV)-35, SV-27, Mosquito Deleto™(MD)-2200, MD-2500, MT150-Power Trap, and two models of The Guardian Mosquito Traps (MK-01 and MK-12). All trap models except the SV-35, the SV-27, the MD-2500, and the MK-12 attracted significantly more females than males. The SV-35 was the most efficient trap, catching significantly more females than all the other models. The MD2200 and MK-12 models were the least effective in catching either female or male sand flies. These data indicate that several models of propane combustion traps might be suitable substitutes for either CO2-baited or unbaited light traps for adult sand fly surveillance tools. One advantageous feature is the traps’ ability to remain operational 24/7 for ca. 20 days on a single tank of propane. Additionally, the models that produce their own electricity to power the trap’s fans have an important logistical advantage in field operations over light traps, which require daily battery exchange and charging. Journal of Vector Ecology 36 (Supplement 1): S166-S171. 2011. Keyword Index: Sand flies, thermoelectric, surveillance, light, carbon dioxide, CDC trap. INTRODUCTION Phlebotomine sand flies have a wide distribution, mainly in the tropics and subtropics (Adler and Theodor 1957). They are proven vectors of leishmaniasis, bartonellosis (Birtles 2001) and numerous viruses including phleboviruses, flaviviruses, orbiviruses and vesiculoviruses (Comer and Tesh 1991, Ashford 2001). Two Leishmania species cause leishmaniasis in the Old World, Leishmania major Yakimimoff and Schokhornin and L. tropica Wright. In Israel, the epidemiology of cutaneous leishmaniasis, due to L. major has been investigated and clearly defined as zoonotic, with Psammomys obesus Cretzschmar and Meriones crassus Sundevall as the main rodent reservoir hosts and Phlebotomus papatasi Scopoli as the vector (Schein et al. 1982, 1984, Wasserburg et al. 2003b, Jaffe et al. 2004) Cutaneous leishmaniasis is endemic in large parts of Israel and the West Bank (Wasserburg et al., 2003a, 2003b, Al-Jawabreh et al. 2004, Jaffe et al. 2004). Phlebotomus papatasi is an important vector of the disease in the Jordan Valley and southern Israel where large sand fly populations are found in the burrows of the rodent reservoirs (Schlein et al. 1982, 1984, Jainini et al. 1995). CDC light traps and sticky papers have been the standard sampling methods for monitoring adult populations of sand flies (Killick-Kendrick 1987, Alexander 2000, Faiman et al. 2009). Recent developments in mosquito monitoring/control technology in the U.S. has resulted in the production of various models of commercial traps for the consumer market, which utilize the combustion of propane to produce carbon dioxide (CO2) and other attractants. While these traps were designed for the collection and control of mosquitoes, they have also been used to collect large numbers of Culicoides spp. (Ceratopogonidae) biting midges (Cilek and Hallmon 2005, Cilek et al. 2003) in the U.S.; some Lutzomyia have been collaterally collected. To our knowledge, no one has conducted any study to compare the efficacy of the various models of these commercially available propane powered traps for the capture of any species of phlebotomine sand fly. Therefore, the major objective of this study was to compare the efficacy of eleven models of propane powered traps to capture P. papatasi. MATERIALS AND METHODS Study site The study was conducted October 11-22, 2005, in a zoonotic focus of L. major in Neot Hakikar oasis in the southern Jordan Valley in Israel. The oasis is known for its rich mosquito fauna (Margalit et al. 1973), however the only sand fly species recovered has been P. papatasi (Schlein et al. 1984, Muller and Schlein 2004). The whole endemic region is classified as an extreme desert and belongs to the Sahara-Arabian phyto-geographical zone (Danin 1988). In this zone, the rainy season is very short and the summer is extremely dry and hot. The annual rainfall is 50 mm in the south and 100 mm in the north (Ashbel 1951). Average daily temperature is 20° C from the end of September to Vol. 36, Supplement 1 Journal of Vector Ecology early April and 30° C from May to August with extreme heat waves of up to 50° C in the summer (Orni and Efrat 1980). Neot Hakikar, the largest oasis on the shore of the Dead Sea, covers an area of about 50 square kilometers. In the oasis there is a small village with irrigated gardens, cultivated fields and green houses. The village is surrounded by natural areas, which include marshland, numerous springs, plains that are flooded in winter by overflow of nearby wadies, which become dried up salt pans in the summer. The vegetation, particularly near the springs, is a rich mixture of Ethiopian and Palearctic flora (Zohary and Orshansky 1949). Within this natural vegetation a date plantation is located. The plantation is surrounded by groves and thickets of trees and bushes like Tamarix nilotica (Ehrenb.) Bge. and T. passerinoides Del. Ex Desv. (Tamaricaceae), Prosopis farcta (Macbride) (Mimosaceae), Nitraria retusa (Forssk.) Asch. (Nitrariaceae) and chenopod bushes like Atriplex halimus (L.), A. leucoclada Boiss., Suaeda asphaltica (Boiss.), S. frutiicosa Forsk. (Chenopodiaceae). Commercial propane-based combustion traps Eleven commercially available trap models were compared. They were similar in that they were all designed to mimic a vertebrate host through the combustion of propane to generate heat, moisture, and CO2 to attract biting insects. The traps differed in physical appearance (e.g. color patterns, shape and height), amount of CO2 produced and point of release, type and location of capturing device, presence/absence of fans, the method (counterflow updraft versus downdraft) used by these fans to vacuum the insects into the collection device, and the power source for the fans (i.e. mains electricity versus thermoelectric generation of electricity by means of propane combustion). The traps were assembled, operated, and maintained according to the manufacturers’ instructions, except that no octenol baits were used based on previously reported studies, which showed that octenol had either no effect or a slightly repellent effect on the collection of P. papatasi (Beavers et al. 2004). Major trap features are summarized in Table 1. The trap models tested were: the Mosquito Magnet™ (MM)-Pro, MM-Liberty, MM-Liberty Plus, and MMDefender (Woodstream, Littiz, PA); Skeeter Vacuum® (SV)27 and SV-35 (Blue Rhino, Winston Salem, NC); Mosquito Deleto™ (MD)-2200 and MD-2500 Active System (The Coleman Company, Wichita, KS); MT150-Power Trap (Flowtron, Malden, MA); and The Guardian Mosquito Traps MK-01 and MK-12 (Lentek/Koolatron, Chicago, IL). In addition to using propane combustion to produce the attractants listed above, five trap models (MM-Pro, MMLiberty Plus, SV-27, SV-35 and MD-2500) utilize some type of thermoelectric module to capture some of the heat produced by the combustion process to produce electricity to power the suction fans. These traps are cordless. The MM-Liberty, MM-Defender, MK-01, MK-12 and the MT 150 Power Trap were provided A.C. (mains) current by the generation of electricity by means of gasoline-powered generators. Only one trap, the MD-2200 did not use a suction fan and therefore had no need for electricity; its S167 attractants were distributed by passive diffusion away from the trap. Various trap models used different collection devices. The MD-2200 used all black sticky (glue) panels to capture attracted insects; the SV-27 and SV-35 used a combination of sticky papers (alternating patterns of black and white) and a specially designed suction collection cup to simultaneously capture attracted insects. The rest of the trap models used vacuum created by suction fans to capture attracted insects into either nets (MM-Pro, MMLiberty, MM-Liberty Plus and MD-2500) or specially designed collection devices (MM-Defender, MT-150 Power Trap, MK-01 and MK-12) . In addition to the attractants generated by propane combustion, five traps used light as an additional attractant. The SV-27 and SV-35 used several colors of flickering LEDs, the MK-01 and MK-12 used a constantly lit blue LED, and the MT-150 used a constantly lit green LED. Experimental design The study was conducted for 11 consecutive nights along the elevated embankment of a drainage canal, which separated a nature reserve from the cultivated areas. Eleven trapping stations, ca. 50 m apart, were established in a continuous line parallel to the drainage canal. A 9-kg (20 lb) propane tank was placed at each trapping station. Each day the traps were rotated clockwise to the next trapping station at 17:00 to reduce positional bias. During the eleven nights of trapping, each trap model was operated at each trapping station for one night. Trap collections were made at 07:00 each day to prevent degradation of the specimens. Statistical analysis Data were first normalized by conversion to square root then subjected to ANOVA (SAS 2003) using the following model statement: Female Male Total = Treatment Position Day Sex, where dependent variables represented numbers of sand flies captured. Treatment was one of the 11 traps, Position was one of the 11 trap locations, and Day was one of the 11 consecutive trapping days of the study. Means were separated with the Ryan-Einot-Gabriel-Welsch Multiple Range Test (REGWQ), and unless otherwise stated, P < 0.05 (SAS 2003). Although square root values were used for the analyses, actual values are reported in the text, figures and tables. RESULTS Main effects models were significant for all three dependent variables (Female, F=14.32, d.f = 30,90, P