Amy Junnila

Effective Control of Adult Culex pipiens by Spraying an Attractive Toxic Sugar Bait Solution in the Vegetation Near Larval Habitats

ABSTRACT This study evaluated the use of an insecticide-treated fruit juice bait against adult Culex pipiens s.l. L. from sewage ponds in Israel. The attractive toxic sugar bait (ATSB) solution (fruit juice, sugar, food dye, oral insecticide spinosad, and BaitStab, a mixture of slow-release substances and preservatives) was sprayed onto 10–15% of the surrounding vegetation of these ponds. The same bait solution, without insecticide, was sprayed onto vegetation at a similar site as a control. Mosquito abundance was monitored in treatment and control sites with six CDC light traps. Mosquitoes in the experimental sites decreased from ≈125 to approximately eight per trap. Mosquito abundance in the control sites was fairly stable and averaged ≈60 per trap during the study. Before starting the study parity of mosquitoes from the experimental and control sites averaged ≈20% muciparous females. After bait/insecticide application, only ≈3% of the females were multiparous in the treatment area.

Control of Culex quinquefasciatus in a storm drain system in Florida using attractive toxic sugar baits.

Attractive toxic sugar baits (ATSBs) were used to control mosquitoes in the storm drains of a residential area on the outskirts of St Augustine, Florida. The drainage system was newly constructed and no mosquitoes were breeding inside it. The area covered by the storm drains was divided in half; 10 drains served as control drains and 16 drains served as experimental drains. The baits, which consisted of a mixture of brown sugar, fruit juice, green dye marker and boric acid, were presented at the entrances of the treated drains and exit traps were positioned over the drain openings and the connecting tubes leading to retention ponds. Similar baits with orange dye and without toxin were presented at the entrances of control drains. A total of 220 pupae of Culex quinquefasciatus (Diptera: Culicidae) were released in each control and toxin‐treated drain, and the numbers of recovered mosquitoes were examined to determine the effectiveness of ATSBs in the storm drain system. An average of 178.2 mosquitoes exited each drain in the control area; 87.0% of these had fed on the baits and were stained orange, whereas 13.0% were unstained. In the toxin‐treated drains, 83.7% of hatched females and 86.6% of hatched males were controlled by the baits.

Evaluation of commercial products for personal protection against mosquitoes.

Human landing catch studies were conducted in a semi-field setting to determine the efficacy of seven commercial products used for personal protection against mosquitoes. Experiments were conducted in two empty, insecticide free, mesh-enclosed greenhouses, in Israel, with either 1500 Aedes albopictus or 1500 Culex pipiens released on consecutive study nights. The products tested in this study were the OFF!(®) Clip-On™ Mosquito Repellent (Metofluthrin 31.2%) and the Terminix(®) ALLCLEAR(®) Sidekick Mosquito Repeller (Cinnamon oil 10.5%; Eugenol 13%; Geranium oil 21%; Peppermint 5.3%; Lemongrass oil 2.6%), which are personal diffusers; Super Band™ Wristband (22% Citronella oil) and the PIC(®) Citronella Plus Wristband (Geraniol 15%; Lemongrass oil 5%, Citronella oil 1%); the Sonic Insect Repeller Keychain; the Mosquito Guard Patch (Oil of Lemon Eucalyptus 80mg), an adhesive-backed sticker for use on textiles; and the Mosquito Patch (vitamin B1 300mg), a transdermal patch. It was determined that the sticker, transdermal patch, wristbands and sonic device did not provide significant protection to volunteers compared with the mosquito attack rate on control volunteers who were not wearing a repellent device. The personal diffusers: - OFF!(®) Clip-On™ and Terminix(®) ALLCLEAR(®) Sidekick - provided superior protection compared with all other devices in this study. These diffusers reduced biting on the arms of volunteers by 96.28% and 95.26% respectively, for Ae. albopictus, and by 94.94% and 92.15% respectively, for Cx. pipiens. In a second trial conducted to compare these devices directly, biting was reduced by the OFF!(®) Clip-On™ and the Terminix(®) ALLCLEAR(®) by 87.55% and 92.83%, respectively, for Ae. albopictus, and by 97.22% and 94.14%, respectively, for Cx. pipiens. There was no significant difference between the performances of the two diffusers for each species.

Species identification of plant tissues from the gut of An. sergentii by DNA analysis

There are three commonly used assays to identify plant material in insect guts: the cold anthrone test for fructose, the cellulose staining test for visualizing plant tissue and gas chromatography for seeking unique sugar content profiles. Though sugar and cellulose tests can distinguish between the general sources of sugar meal (nectar versus tissue), they cannot identify the species of plant sources. Even gas chromatography profiles can be problematic; there are reported instances of intra-specific variation as well as inter-specific and intergeneric variation that can mar results. Here, we explore the potential for DNA analysis to help resolve this issue. First, Anopheles sergentii were exposed to branches of two species of highly attractive flowering bushes in the laboratory and the great majority ( approximately 90-98%) were positive for sugar from nectar while very few were positive for cellulose ( approximately 0.5-8%) and DNA (6-19%). Moreover, laboratory An. sergentii showed opposing preferences, tending to obtain sugar from nectar of one plant (Tamarix nilotica) but to feed more on tissue from the other (Ochradenus baccatus). An. sergentii are exposed to a wide variety of plants in their natural desert habitats and in the absence of flowers in the dry season, they resort to feeding specifically on tissues of a few plants. According to DNA analysis the favorite plants were Suaeda asphaltica, Malva nicaeensis and Conyza dioscoridis, which are succulents that account for less than 1% of vegetation in the area.

Efficacy of attractive toxic sugar baits (ATSB) against Aedes albopictus with garlic oil encapsulated in beta-cyclodextrin as the active ingredient.

We tested the efficacy of attractive toxic sugar bait (ATSB) with garlic oil microencapsulated in beta-cyclodextrin as active ingredient against Aedes albopictus in suburban Haifa, Israel. Two three-acre gardens with high numbers of Ae. albopictus were selected for perimeter spray treatment with ATSB and ASB (bait containing no active ingredient). Baits were colored with food dye to verify feeding of the mosquitoes. The mosquito population was monitored by human landing catches and sweep net catches in the surrounding vegetation. Experiments lasted for 44 days. Treatment occurred on day 13. The mosquito population collapsed about 4 days after treatment and continued to drop steadily for 27 days until the end of the study. At the experimental site the average pre-treatment landing rate was 17.2 per 5mins. Two days post-treatment, the landing rate dropped to 11.4, and continued to drop to an average of 2.6 during the following 26 days. During the same period, the control population was stable. Few sugar fed females (8-10%) approached a human bait and anthrone tests showed relatively small amounts of sugar within their crop/gut. Around 60-70 % of males caught near our human bait were sugar positive which may indicate that the males were feeding on sugar for mating related behavior. From the vegetation treated with the toxic bait, we recovered significantly fewer (about 10-14%) males and females stained by ATSB than at the ASB-treated control. This may indicate that the toxic baits alter the resting behavior of the poisoned mosquitoes within the vegetation. Almost no Ae. albopictus females (5.2±1.4) approached human bait after treatment with ATSB. It therefore appears that microencapsulated garlic oil is an effective pesticide against Ae. albopictus when used in an ATSB system.

Understanding attraction stimuli of the cat flea, Ctenocephalides felis, in non-chemical control methods

Comparisons were conducted of flea catches of four commercially available flea traps in the laboratory and under field conditions, in both rural and urban locations. The results clearly showed the My Flea Trap™, which utilizes an intermittent light to attract fleas, to be far superior in trapping ability to the three continuous light traps; it caught up to 23 times as many fleas as the other traps. Altering the lighting mechanism to provide continuous rather than intermittent light significantly decreased the number of fleas captured. In addition, the use of a green filter significantly increased trapping efficiency, whereas the addition of a heat source had no apparent effect.

Reduction of mosquito biting pressure by timed-release 0.3% aerosolized geraniol

We conducted a study to determine the degree of personal protection provided by the Terminix(®) ALLCLEAR(®) Mosquito Mister - Lantern Edition. This outdoor unit was operated to disperse an aerosolized aqueous 0.3% geraniol emulsion in timed-release intervals of 5.0, 7.5, and 10.0 min. Human volunteers participated in landing catch experiments to test the effect of geraniol sprayed at pre-set time intervals, at two distances: (1) 18 ft (5.49 m), the maximum effective distance claimed by the manufacturer, and (2) 9 ft (2.74 m), half the effective distance from the unit. When aerosolized geraniol was dispensed, reductions in biting pressure (landing, probing and biting mosquitoes) of Culex pipiens and Aedes albopictus, at all times and distances, were evident compared to dispensation of the water spray control. The degree of protection correlated well with the distance from the subject and the time interval of releases. The 5 min time interval mode reduced overall biting pressure by more than 90% at 9 ft (2.74 m) and 18 ft (5.49 m). Reduction of biting pressure in the 7.5 min mode was still well over 80% and even in the 10 min mode, overall protection was slightly above 80% at a distance of 9 ft. The lowest but still reasonable protection level was observed in the 10 min mode, at the periphery of the area the unit claims to protect (300 ft(2)), with a biting pressure reduction of approximately two-thirds.

Comparative efficacy of small commercial traps for the capture of adult Phlebotomus papatasi

ABSTRACT: We tested the performance of ten commercial mosquito traps with varying attractive features, against three CDC traps (an unlit model 512, an incandescently lit model 512, and a UV lit model 1212) as well as simple sticky paper, for their ability to attract and capture Phlebotomus papatasi in Israel. The commercial traps tested were the Sentinel 360, the Combo Trap, the Mega Catch Premier, the Bug Eater, the EcoTrap, the Galaxie Power-Vac, the Biter Fighter, the Black Hole, the Mosquito Trap, the Mosquito Catcher, the Sonic Web, the Solar Pest Killer, and a Bug Zapper. The four best performing traps with the highest nightly catches were the Sentinel 360 (85.96±19.34), the Combo Trap (70.00±7.78), the Mega Catch Premier (51.93±1.82) and the UV lit CDC 1212 trap (47.64±3.43). Five traps, the Mosquito Trap, the Mosquito Catcher, the Sonic Web, the Solar Pest Killer, and the Bug Zapper, performed exceptionally poorly, catching an average of less than two sand flies per day. To our knowledge, this is the first comprehensive attempt to evaluate commercial traps for their effectiveness in catching sand flies, and we show here that some traps that have been effective in catching mosquitoes are also effective in catching sand flies.

Attraction of Phlebotomus papatasi to Common Fruit in the Field

ABSTRACT: Sand flies have been reported feeding on various plant organs including stems, leaves, and flowers but the attraction of sand flies to sugar-rich fruits has received little attention. In this study, we tested 24 commercially available fruits for their attractiveness to sand flies, and found that the top three attractive fruits were nectarine (Prunus persica var. nectarina), cactus fruit, (Opuntia ficus-indica), and guava (Psidium guajava). These fruits were fed upon equally by both males and females. There were slight differences in the order of preference to the less-attractive fruits by males and females, but these were not statistically significant. The knowledge of fruit preference may help to improve existing methods that use plant phytochemicals to attract and kill biting flies.

Identification of plant tissues from the gut of Phlebotomus papatasi by DNA analysis

Sugar and cellulose assays can determine if an insect has fed on sugar and plant tissue but they cannot identify the species of source plant. In this study, we used DNA analysis together with traditional cellulose and sugar assays to examine the plant feeding habits of wild Phlebotomus papatasi during the dry season in the Lower Jordan Valley, Israel. About 37% of the sand flies were positive for sugar, 45% were positive for cellulose in the gut, and 41% contained amplifiable plant DNA. All of the plant DNA fragments sequenced from both males and females were identified as Suaeda asphaltica.