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Among the various insecticides evaluated for their field efficacy against pod borers of Indian bean, the treatment of emamectin benzoate 5SG at 0.002%, indoxacarb 14.5SC at 0.007% and lambdacyhalothrin 5SC at 0.005% were found to be most effective against Helicoverpa armigera (Hubner) and Maruca vitrata Geyer. While, thiacloprid 21.7SC at 0.012% and novaluron 10EC at 0.01% were moderately effective. The least pod damage was observed with emamectin benzoate 5SG at 0.002% (13.16%) which was at par with indoxacarb 14.5SC at 0.007% (14.16%) and lambdacyhalothrin 5SC at 0.005% (16.33%). Maximum pod yield (21.75 q/ha), increase in yield over control (95.76%) and % of avoidable loss (48.91%) was observed with emamectin benzoate 5SG at 0.002%. [ABSTRACT FROM AUTHOR]

Among the various insecticides evaluated for their field efficacy against sucking pests of Indian bean, the treatments of thiamethoxam 25WG at 0.025%, acetamiprid 20SP at 0.004% and buprofezin 25SC at 0.05% were found to be the most effective against Aphis craccivora Koch, Empoasca kerri Pruthi and Bemisia tabaci Gennadius. While, thiacloprid 21.7SC at 0.012% emerged as the moderately effective. Emamectin benzoate 5SG at 0.002%, indoxacarb 14.5SC at 0.007%, lambda-cyhalothrin 5SC at 0.005% and novaluron 10EC at 0.01% were found to be less effective. [ABSTRACT FROM AUTHOR]

Abstract Background Pyrethroids are used for insect control. They act on voltage-gated sodium channels in neurons. Lambdacyhalothrin (LCH) is a type II pyrethroid producing choreoatetosis and salivation in rodents. Vascular endothelial growth factor (VEGF) expression in the kidney is high in the glomerular podocytes and kidney tubules. VEGF receptor 2 (VEFGR2) is the main mediator in angiogenesis and it regulates blood vessel permeability. Lack of VEGF in podocytes impairs filtration. The nuclear factor κB (NFκB) is widely known as an important mediator of inflammation. The aim of the study was to check if subacute oral intoxication with 0.1LD50 of LCH affects kidney size, function and VEGFR2 and NFκB in mice kidneys. Methods A total of 32 Albino Swiss mice was used: females controls, males controls, females receiving 2 mg/kg LCH, males receiving 2 mg/kg LCH orally for 7 days. On day 8 animals were sacrificed, blood and kidneys were obtained. Kidney mass was determined, creatinine concentration was measured in blood sera, VEGFR2 and NFκB in kidney homogenate supernatant with ELISA kit. Results There was no statistically significant differences in kidney mass, creatinine concentration in blood sera nor NFκB but mean VEGFR2 concentration in the kidneys of females exposed to LCH was 128.01 ng/ml and showed statistically significant difference in comparison with control females. There was no statistically significant difference between VEGFR2 concentration in the kidneys of males exposed to LCH and control males. Conclusion The VEGFR2 increases in the course of LCH intoxication in females probably due to the protective effect of oestrogens.

Background: Pyrethroids are used for insect control. They act on voltage-gated sodium channels in neurons. Lambdacyhalothrin (LCH) is a type II pyrethroid producing choreoatetosis and salivation in rodents. Vascular endothelial growth factor (VEGF) expression in the kidney is high in the glomerular podocytes and kidney tubules. VEGF receptor 2 (VEFGR2) is the main mediator in angiogenesis and it regulates blood vessel permeability. Lack of VEGF in podocytes impairs filtration. The nuclear factor κB (NFκB) is widely known as an important mediator of inflammation. The aim of the study was to check if subacute oral intoxication with 0.1LD50 of LCH affects kidney size, function and VEGFR2 and NFκB in mice kidneys.Methods: A total of 32 Albino Swiss mice was used: females controls, males controls, females receiving 2 mg/kg LCH, males receiving 2 mg/kg LCH orally for 7 days. On day 8 animals were sacrificed, blood and kidneys were obtained. Kidney mass was determined, creatinine concentration was measured in blood sera, VEGFR2 and NFκB in kidney homogenate supernatant with ELISA kit.Results: There was no statistically significant differences in kidney mass, creatinine concentration in blood sera nor NFκB but mean VEGFR2 concentration in the kidneys of females exposed to LCH was 128.01 ng/ml and showed statistically significant difference in comparison with control females. There was no statistically significant difference between VEGFR2 concentration in the kidneys of males exposed to LCH and control males.Conclusion: The VEGFR2 increases in the course of LCH intoxication in females probably due to the protective effect of oestrogens. [ABSTRACT FROM AUTHOR]

Introduction. Pyrethroids are commonly used in agriculture and for indoor insect control. They act as neurotoxins mainly via sodium channels in neurons. People can be exposed to traces of these xenobiotics dermally, with food, at home or at workplace. Three pyrethroids: cypermethrin, lambdacyhalothrin, and betacyfluthrin were chosen for modelling subacute oral poisoning in mice.The aim of the study was to assess if 7-day exposure to 0.1LD50 of each compound could impair memory and motor activity in mice.Material and methods. A total of 64 mice were divided into 8 groups of 8 animals: females controls, males controls, females receiving cypermethrin, males receiving cypermethrin, females receiving lambdacyhalothrin, males receiving lambdacyhalothrin, females receiving betacyfluthrin, males receiving betacyfluthrin. They were given 0.1LD50 of a pyrethroid dissolved in canola oil by gavage daily for 7 days. They were tested in a Y-maze on day 1 and 7.Results. Subacute poisoning with betacyfluthrin significantly reduces locomotor activity in females on day 1 and in both genders on day 7 without effect on fresh spatial memory.Conclusion. Betacyfluthrin is the most harmful of the tested pesticides.

Culex quinquefasciatus Say is a vector for lymphatic filariasis in human populations throughout the world. Vector control, a major strategy for eradication of filariasis mainly involves the application of chemical insecticides giving rise to resistance against insecticides. In this context, a study was conducted to find out the resistance status of Cx. quinquefasciatus populations from seven densely populated sites in Siliguri sub division, West Bengal. Larval bioassay against temephos and adult bioassay against 5% malathion, 0.05% deltamethrin and 0.05% lambdacyhalothrin was performed following the standard WHO protocol. A total of 630 larvae and 360 adults were tested from one sampling site. The activity of major insecticide detoxifying enzymes i.e., carboxylesterases and monooxygenases was also assessed through biochemical assay. The seven tested populations were found to exhibit moderate to severe resistance (27.27% - 83.33% mortality) against deltamethrin, lambdacyhalothrin and temephos. However, all of the seven populations were found to be completely susceptible to malathion. This study provides new information on the current status of insecticide resistance in Cx. quinquefasciatus from this area, which may be helpful to the concerned authorities to design an effective mosquito control strategy for efficient management of vector-borne diseases. [ABSTRACT FROM AUTHOR]

The current study was performed to assess the relative acaricidal toxicity of three miticides (abamectin, fenpyroximate, pyridaben), one insecticide (lambda-cyhalothrin), one mineral oil and one plant extract (Allium sativum) with different mode of actions against Tetranychus urticae under laboratory and field experiments. The results revealed that abamectin was the highest toxic compound followed by lambda-cyhalothrin with LC50 values of 0.15 and 16.48 ppm, respectively, while Allium sativum extract was the lowest one with LC50 value of 2869.49 ppm. All tested compounds reduced oviposition and hatchability of T. urticae compared to control. Abamectin and X-cyhalothrin were the most effective compounds in reducing oviposition and hatchability process of T. urticae, while Allium sativum extract had the least influence. Regarding the field experiment, abamectin had the highest reduction percent (95%) again the T. urticae motile stages population. X-cyhalothrin exhibited remarkable acaricidal activity (88.58%) despite being an insecticide also Allium sativum extract achieved satisfied reduction percent (77.23%). Therefore, the role of Allium sativum extract should be considered in an integrated pest management program in order to reduce pesticide risks and costs. Further work is required to prepare Allium sativum extract in an appropriate formulation to enhance its activity. [ABSTRACT FROM AUTHOR]

Indiscriminate application of pesticides in paddy crop field soil to enhance paddy production could cause adverse impact on the both soil fertility and bacterial communities. The present study aimed to isolate bacteria prevalent in Lambdacyhalothrin exposed soil to determine their Lambdacyhalothrin degrading ability and assay the degraded metabolites. The observations registered in this study revealed that the dominant bacteria isolated from paddy crop field soil were Bacillus cereus and Aneurinibacillus migulanus. These bacteria were inoculated in soil spiked with Lambdacyhalothrin. After 36 hours of inocubation, the extract were analysed by GCMS. Lambdacyhalothrin degradation was accelerated by Aneurinibacillus migulanus (100 % of pesticide degraded compared to Bacillus cereus 94.09 % and control 55.2 % ). Thus Aneurinibacillus migulanus could be the used as bioagents to degrade lambdacyhalothrin.

The aim of the present work was to study the potential mutagenic and cytotoxic effects of synthetic pyrethroid insecticide Lambada 5EK in the root meristems of some vegetables. Two concentrations of the pesticide were investigated (0.03% - recommended in agricultural practices, and tenfold lower concentration - 0.003%), and three plant-species, widely used as food, were tested - sweet and hot pepper (Capsicum annuum L.), beetroot (Beta vulgaris L.) and onion (Allium cepa L.). The results obtained regarding the influence of pesticide on mitotic cell division and chromosome status showed that the species have different sensitivity towards the pesticide action. The hot pepper was the most sensitive of all the tested plant species towards the impact of the pesticide in mitosis, and lower mitotic index values were recorded in both tested concentrations compared to the control. The most common observed chromosomal aberrations were: anaphase/telophase bridges, lagging acentric chromosome and/or chromosome fragments, and cells with micronuclei; they were found in all tested plant species, except beetroot treated with 0.003% solution of the pesticide. These results suggested that the beetroot possesses some endurance to the mutagenic action of the insecticide and probably it is an appropriate culture in crop rotation in agricultural practice when lambda-cyhalothrin pesticides have been used. [ABSTRACT FROM AUTHOR]

The electrochemical oxidation of lambdacyhalotrin in a triton X-100 water solution on a PbO2-Bi electrode has been studied. It was discovered that electrocatalytic degradation proceeded through the Langmuir-Hinshelwood (L-H) mechanism. The Langmuir adsorption equilibrium constant of the organic compound on the PbO2-Bi surface (0.67 (±0.02) mg-1L) and the L-H maximum reaction rate for lambdacyhalotrin oxidation (0.040 (±0.002) mg L-1 min-1) was also determined on the basis of kinetic data. Oxidation/mineralization was tested at electrode potential higher than 2.3 V vs. Ag/AgCl, in this conditions the higher degradation percent of 85 (±4) % has been obtained.

Knemidocoptic mange is occasionally noted in pet chickens. The etiologic agent of this disease is Knemidocoptes gallinae and K.mutans, a sarcoptiform mite. These mites live out their entire life cycle on their hosts. Typically, the crusty and scaly dermatitis associated with this mite is seen at the feet and legs, as may be seen in some pet canaries or budgerigars with the same problem. Facial lesions, however, are particularly uncommonly seen in chickens. A suggestive diagnosis can be established by physical examination findings of a "honeycombed" appearance to the crusts and scales on the feet and legs, or by skin scraping. Treatment is with ivermectin, which may be repeated in 2-week intervals for 2 to 3 total treatments. Not all birds exposed to a bird with this condition necessarily will develop problems, and group treatment is not necessarily always required Cedrus oil a herbal product was trid agains knemidocoptes gallinae and its efficacy was compared with of Zizyphus Extract and Rotenone-orthophenol. In this study 16 broiler with knemidocoptes gallinae infestion treated with cedrus oil and Zizyphus extract .Mite scrapings after topical application of cedrus oil caused complet recovery after 20 days in severe infestation with growth of feather on days 20 post treatment. Adverse reactions were observed the following of lambdacyhalothrin were used.

Background and Objective: Human flea is assumed as the most dominant ectoparasite associated with transmitting diseases via biting humans. Insecticides are widely employed to curb this vector. Assessment of susceptibility level of populations to various pesticides is necessary for taking appropriate control measures. Materials and Methods: Subsequent to collection of human flee from indoor areas of Khodabandeh and Mahneshan located in Zanjan province from August 2013 to November 2014, they were kept under standard laboratory conditions. The samples were exposed to inconsistent doses of Permethrin and Lambdacyhalothrin and consequently their mortality rates were assessed after 24 hours. Results: Out of 1074 collected fleas, 88.1% were Pulex irritans, 7.2% Ctenocephalides cani and 4.7% C. felis. Bioassay[s1] results gave evidence to homogeneity of study population. LD50 values for permethrin and lambdacyhalothrin were 288.40 - 295.15 µg/ cm2 and 21.87 - 24.54 µg/cm2, respectively. Conclusion: High levels of LD50 values to pyrethroides of human flea in the studied area indicated the requirement of more attention of health workers to control the vector and Further[s2] research is necessary to assess the resistance status of human flea to alternative effective insecticides. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the comparative efficacy of neem leaf extracts and lambdacyhalothrin against whitefly and jassid in okra field. Four okra cultivars (SABZ PARI, SADA BAHAR, PUS A SAWANI, ARKA and ANAMIKA) were grown in field with four replication. Five neem oil concentrations (1, 2, 3, 4 and 5 percent) and a synthetic insecticide (Lambdacyhalothrin 2.5EC) @ 330 mL acre were applied to evaluate efficacy effects on targeted insects population. Distilled water was used as control. The plots treated with synthetic insecticide and the leaf extracts against targeted pests had significantly (P > 0.05) suppressed insect population as compared to control. After 1st spray, no significant (P > 0.05) reduction in pest populations were observed after 24 hours. However, significant (P < 0.05) reduction in population was recorded after 48 and 72 hours respectively. The decline in efficacy of insecticides were recorded after 360 hours of spray. Lambdacyhalothrin and neem oil @ 4 and 5% concentration were equally effective against whitefly and jassid feeding on okra plants. The efficacious effect of neem oil and synthetic insecticide on plant height, number of pods/plant and yield were also studied. Furthermore, tested treatments had no significant effect on plant height and yield parameter (number of fruits pods plant). Whereas, tested treatments of neem oil @ 4 and 5% and lambdacyhalothrin had induce significantly (P > 0.05) impact on yield parameter (yield). We conclude that Lambdacyhalothrin and neem oil @ 4 and 5% concentration are equally effective in controlling jassid and have same impact on yield of okra plant. [ABSTRACT FROM AUTHOR]

The comparative toxicity of two Emamectin benzoate [(Speedo5.7% WG) and (Basha 1.9% EC)], two Lambdacyhalothrin [(Bestend 10% WP) and (Max sped 5% EC)] were examined against the cotton leafworm Spodoptera littoralis (Boisd.) 4th larval stage on castor bean leaves. The effect of rate spreading droplets on the toxicity of Emamectin benzoate and Lambdacyhalothrin formulations were investigated under laboratory conditions. The results showed that Lambdacyhalothrin (Max sped 5%Ec) exhibited the highest toxicity against the fourth larval stage of S. littoralis with LC50 values of 0.007 ppm. In contrast, Lambdacyhalothrin,( Bestend 10% WP) had the lowest toxicity with LC50 values of 0.033 ppm. On the other hand, the Emamectin benzoate (Speedo5.7% WG) was given the lowest LC50 value of 0.0061 ppm followed by (Basha 1.9% EC) LC50 value of 0.0097 ppm. The results of joint toxic effect between rate spreading droplets and insecticides indicated that Emulsifiable concentrate of Lambdacyhalothrin and Emamectin benzoate formulation was the highest both rate spreading droplets and the mortality rates [ABSTRACT FROM AUTHOR]

Insecticidal residual effect and triatomine infestation rates in houses of a community fumigated with lambdcyhalothrin (Icon) are reported. No mortality was observed in 5th-instar Triatoma infestans nymphs in 72-hr exposure test on three different surfaces, one month after fumigation for a dose of 31.5 mg am/m2. However, during post-exposure observation a mortality of 60% was recorded for those insect exposed on sprayed woodboard. The results observed with mud-containing treated walls, were markedly poorer (0% of mortality). Twelve month after spraying 40% of mortality was observed on first-instar T. infestans nymphs in 72-hr exposure test on woodboard, but lower mortality rates were observed in mud-containing materials. When the effect of deltamethrin (109 mg ai/m2) and lambdcyhalothrin (94 mg ai/m2) was compared, the former did not appear to be superior at similar loads. Both have showed a mortality rate of 30% on 5th-instar T. infestans nymphs three months post-fumigation. The dose utilized in the field fumigation was enough to get a significant (p < 0.0001) control of triatomine domestic infestation, since it was sufficient to keep 95% of the houses uninfested throughout 21 months following treatment, when compared with baseline situation. A remarkable knock-down effect on adult and nymphs forms of the insect and a high in situ mortality were observed as a result of its application, even at very low doses.

Dark rover ants (Brachymyrmex patagonicus, Mayr) are an exotic ant species native to South America that has recently spread through the southern US. We evaluated the residual activity of three liquid insecticides (indoxacarb, fipronil and lambda-cyhalothrin) as potential barrier treatments against these ants. The factors we considered include the use of a porous or non-porous surface, a short or long exposure time and the changes in insecticide activity after treatment during a 90 day period. We also tested the effect of baits containing three different active ingredients (imidacloprid, sodium tetraborate and indoxacarb) on colony fragments of this species for a 15 day period. Both lambda-cyhalothrin® and indoxacarb® resulted in high levels of ant mortality up to 90 days after application. The results of exposure to fipronil® resembled those from the control treatment. Application of insecticides on a porous surface and the shorter exposure time generally resulted in greater ant survival. Of the baits tested, only the imidacloprid based one decreased ant survival significantly during the evaluation period. Within three days, the imidacloprid bait produced over 50% mortality which increased to over 95% by the end of the experiment. Results from the other two bait treatments were not significantly different from the control. [ABSTRACT FROM AUTHOR]

Background & objectives: Selection of an insecticide and its appropriate formulation is a prerequisite of formulating any chemical control strategy against vectors. A hut scale field trial was carried out to study the effectiveness of house spraying with capsule suspension (CS) formulation of lambdacyhalothrin in comparison with its wettable powder (WP) formulation on mortality, density and behaviour of malaria vector in Malkangiri district, Odisha, India. Methods: The two formulations were tested at 20 and 30 mg (a.i.)/m² for their effectiveness in terms of deterrence, excito-repellency, blood-feeding success, mortality and residual activity against Anopheles luviatilis, the major malaria vector, in experimental huts in Malkangiri district, Odisha State, India. Results: Both CS and WP formulations prevented the entry of An. luviatilis in to the sprayed huts by >90 per cent for >6 months, the entire peak malaria transmission season in the area. The exit rate increased (90-99%) with different treatments and the feeding rate was reduced (91-97%). There was no significant difference between WP 30, CS 20 and CS 30 mg/m² in these respects. However, WP 20 mg/m² caused a lesser effect than the other three groups. The formulations or the dosages differed only in causing vector mortalities. Overall, the total mortality rate of An. luviatilis was higher in the huts sprayed with CS 30 (58%) than the huts sprayed with CS 20 (48%), WP 20 (37%) and WP 30 mg/m² (47%). Interpretation & conclusions: Considering the duration of residual action and the effect on entry, exit, feeding and mortality of An. luviatilis, the dosage 20 mg/m² of CS formulation of lambdacyhalothrin could be considered for further use. [ABSTRACT FROM AUTHOR]

An investigation was made to study the residual activity and air-borne effect of lambdacyhalothrin (Icon 10 WP) at 30, 40 and 50 a.i. mg/rn2 against An.stephensi in hut scale trials on different surfaces in Mamasani, and Rudan, south of Iran. Bio-assay contact mortality test with Icon at 30 a.i. mgl/m2 on plaster, cement and wood surfaces decreased from 100% to 51.4%, 53% and 63.8% after 84, 80 and 107 days of hut spraying, respectively. At 40 a.i mg/m2 Icon showed longer residual activity than the 30 mg/rn2, i.e. the mortality rate deceased from 100% to 50.7% for plaster, to 52.5% for cement and to 53.5% for wood surfaces, after 105, 105 and 124 days of hut spraying, respectively. Icon at 50 a.i. mg/m2 showed longer residual activity than the former dosages, i.e. the mortality dropped from 100% to 62.1% for plaster, to 50.7% for cement and to 90.4% for wooden surfaces, after 124 days of hut spraying, respectively. The result of air home tests showed that Icon has negligible or slight killing effect on An.stephensi, i.e. at 30. 40 and 50 a.i. mg/m2, the mortality rates dropped from 100% to about 60% after 10, 15 and 25 days of hut spraying, respectively. Based on the results of this study lambdacyhalothrin at 50/m2 had a residual activity for more than 4 months on different surface. It could be concluded that, lambdacyhalothrin at 50 mg/m2 might be a candidate dosage for continuation of study in village scale vial in south of Iran.

Porous/magnetic molecularly imprinted polymers ( PM- MIPs) were prepared by Pickering emulsion polymerization. The reaction was carried out in an oil/water emulsion using magnetic halloysite nanotubes as the stabilizer instead of a toxic surfactant. In the oil phase, the imprinting process was conducted by radical polymerization of functional and cross-linked monomers, and porogen chloroform generated steam under the high reaction temperature, which resulted in some pores decorated with easily accessible molecular binding sites within the as-made PM- MIPs. The characterization demonstrated that the PM- MIPs were porous and magnetic inorganic-polymer composite microparticles with magnetic sensitivity ( Ms = 0.7448 emu/g), thermal stability (below 473 K) and magnetic stability (over the pH range of 2.0-8.0). The PM- MIPs were used as a sorbent for the selective binding of lambdacyhalothrin ( LC) and rapidly separated under an external magnetic field. The Freundlich isotherm model gave a good fit to the experimental data. The adsorption kinetics of the PM- MIPs was well described by pseudo-second-order kinetics, indicating that the chemical process could be the rate-limiting step in the adsorption of LC. The selective recognition experiments exhibited the outstanding selective adsorption effect of the PM- MIPs for target LC. Moreover, the PM- MIPs regeneration without significant loss in adsorption capacity was demonstrated by at least four repeated cycles. [ABSTRACT FROM AUTHOR]

Shoot and fruit borer, Leucinodes orbonalis Guenee, is a serious pest of eggplant ( Solanum melongena L.). Management practices of this obnoxious pest are limited to frequent spray of chemical insecticides. Due to increasing levels of resistance of L. orbonalis to different insecticides there is an urgent need to test new chemicals. In this study, nine insecticides such as azadirachtin 0.03EC, abamectin 1.8EC, flubendiamide 24WG, chlorpyriphos 20EC, cartap 50SP, carbosulfan 20EC, thiodicarb 75WP, cypermethrin 10EC, and lambdacyhalothrin 2.5EC belonging to different chemical groups were tested against eggplant shoot and fruit borer in laboratory and field. In laboratory trial, carbosulfan and flubendiamide showed the highest toxicity against fourth instar larvae of L. orbonalis after 24 and 48 h of exposure, respectively. In field trials, they reduced more than 80% shoot and fruit infestation in winter, and 80% shoot and 70% fruit infestation in summer over control. Carbosulfan protected the highest amount of healthy fruit yield in both cropping seasons. Flubendiamide also showed the similar efficacy. Cartap and thiodicarb were moderately effective in both the seasons. Efficacy of cypermethrin and abamectin was moderate in winter but low in summer. Lambdacyhalothrin and chlorpyriphos although reduced shoot and fruit infestation of eggplant and protected higher yield as compared to control, their effectiveness was not satisfactory. The performance of azadirachtin against the pest both in the laboratory and field trials was the poorest while that of carbosulfan and flubendiamide was the best. Thus, it is suggested that carbosulfan and flubendiamide may be used for the control of L. orbonalis in eggplant. [ABSTRACT FROM AUTHOR]

Susceptibility of field populations of Helicoverpa armigera (Lepidoptera: Noctuidae) from Punjab, Pakistan to selected insecticides was evaluated using the leaf dip method. The resistance factors varied between populations. The general trends were low to moderate resistance to endosulfan; very low to low resistance to chlorpyrifos and profenofos; very low resistance to spinosad, indoxacarb and thiodicarb; moderate to high resistance to bifenthrin; high to very high resistance to cypermethrin; and very high resistance to lambda-cyhalothrin. Integrated pest management strategies aimed at reducing pesticide application, such as rotating the conventional insecticides having low resistance with newly developed synthetic insecticides and conserving natural enemies, are recommended. [ABSTRACT FROM AUTHOR]

To develop new population control methods for the Mediterranean fruit fly, Ceratitis capitata, a study comparing bait application techniques (BAT) with a female-biased mass trapping strategy was carried out in seven citrus orchards in Mallorca (Balearic Islands, Spain). In the BAT treatment, fenthion, lambda-cyhalothrin and spinosad were applied separately in three of the orchards. In the other three, the mass trapping strategy (Probodelt traps baited with Biolure©) was adopted at a density of 50 traps/ha, reinforced when necessary with the same insecticide bait application (MTR). The seventh orchard was organically farmed and only mass trapping was used for control, but with a higher trap density (80 traps/ha). For pest monitoring, 2 traps/ha baited with Biolure© (for females and males) and 2 traps/ha baited with trimedlure (for males only) per orchard were inspected weekly. The most effective treatment was the MTR (with fenthion) programme, reducing the C. capitata female population by up to 68% [an average of 3.9 females/trap/day (f/t/d) were obtained vs . 12.6 f/t/d from BAT]. However, the lowest average C. capitata population (between the MTR programmes) was obtained by mass trapping supplemented with lambda-cyhalothrin (only 3.3 f/t/d). When only BAT was applied, applications with lambda-cyhalothrin proved to be the most effective (7.1 f/t/d). However, MTR carried out in the organic orchard resulted in the lowest female captures (2.0 f/t/d). Very little fruit damage was recorded in the treatment orchards. In all BAT treatments, the relative number of males and females was similar; however, in the MTR treatments fewer females than males were recorded in the same orchard. [ABSTRACT FROM AUTHOR]

Background & objectives: Insecticide treated mosquito nets are increasingly being used in malaria control programmes. One of the problems with the treatment of bed nets with conventional formulations of insecticides was that regular washing of treated nets diminish insecticidal effect. Lambdacyhalothrin 2.5 capsule suspension (CS) (2.5 % a.i., w/v), a new water-based microencapsulated formulation Ls reported to have wash- resistant property and longer persistence on the netting material than other formulations. We evaluated the impact of the use of nylon bed nets treated with lambdacyhalothrin 2.5 CS at 10 mg (a.i.)/m² in comparison to untreated nets and no nets on malaria in tribal villages in Orissa. Methods: Nine foothill villages, highly endemic for falciparum malaria, from the Primary Health Centre (PHC) areas of Khairput and Kudumulugumma of Malkangiri district, Orissa, were divided into three groups, each with a population of about 500 and allocated randomly for treated (TN) and untreated nets (UN) and no nets (NN). Bed nets were distributed in September 2001 and retreatment was done in June 2002. The impact was assessed based on the changes in vector density, parous rate, malaria incidence and parasite rates. Indoor-resting collections of Anopheles fluviatilis and An. culicifacies were made at fortnightly intervals from fixed human dwellings. Mass blood surveys before and after distribution of nets and fortnightly active surveillance were carried out to assess the change in parasite rates and malaria incidence. Bioassays were conducted at fortnightly intervals on the bed nets supplied to the villagers. Results: The reductions in indoor resting catches of An. fluviatilis and An. culicifacies were 96 and 38 per cent in villages with treated nets and 2.6 and 23 per cent in villages with untreated nets respectively compared to no net villages. For six months following treatment, 100 per cent mortality of An. fluviatilis was observed on the unwashed nets and on the nets washed once or twice. After re-treatment, 100 per cent mortality of An. fluviatilis or An. culicifacies was observed for nine months even after two washes. Usage rates of treated and untreated nets varied seasonally; 58.9 and 46.3 per cent in rainy season, 48.6 and 37.1 per cent in winter season and 38.1 and 31.6 per cent in summer season respectively. Reductions in malaria parasite rates were about 65 per cent in the treated net villages and 39 per cent in the untreated net villages compared to no net villages. About 75 per cent of treated nets and 60 per cent of untreated nets were in usable condition 19 months after distribution. Interpretation & conclusions: The estimated protection factor based on malaria incidence was 86 per cent for the treated nets during both post-treatment and post-retreatment periods and 34 and 51 per cent for untreated nets for the corresponding periods compared to no nets. The results of the study showed that the use of bed nets treated nets with CS formulation of lambdacyhalothrin at 10 mg (a.i.)/m² was acceptable to the community and re-treatment of nets at nine-monthly intervals can significantly reduce density and survival of An. fluviatilis and incidence of falciparum malaria. [ABSTRACT FROM AUTHOR]

Abstract: The wash resistance of factory produced PermaNets (with deltamethrin bonded to the netting with a resin) was studied by bioassays with Anopheles stephensi. Commercial detergent powders were used to wash the nets. For comparison, conventionally treated nets were washed and bio-assayed. Nets were washed under laboratory conditions using a Rotary shaker for 10min. Mosquito bioassays used standard WHO plastic cones with an exposure time of 3min. The PermaNet caused almost a 100% mortality of An. stephensi after up to 18 washes and >80% mortality up to 26 washes but after 30 washes mortality declined. The differences between the mortality of An. stephensi on treated nets washed with detergent or soap (uncoloured, non-perfumed) were not significant. When conventional nets dipped in deltamethrin (25mg/m2) or lambdacyhalothrin (10mg/m2) were washed under similar laboratory conditions, the wash resistance was markedly less than that of the PermaNet. In the case of deltamethrin, mosquito mortality remained >80% up to 12 washes and with lambdacyhalothrin mortality remained above 80% up to 11 washes. The relationship of 80% mortality from a 3min bioassay to effectiveness against free flying mosquitoes remains to be determined. [Copyright &y& Elsevier]

We conducted a community-randomized controlled trial in an area of moderate malaria transmission in the Amazon region, southern Venezuela, home of the Yanomami indigenous ethnic group. The aim was to compare the malaria incidence rate in villages with lambdacyhalothrin-treated hammock nets (ITHN) or with placebo-treated hammock nets (PTHN). In both arms of the study, intensive surveillance for early case detection was maintained and prompt malaria treatment was administered. Baseline data were collected before the intervention and a population of around 924 Yanomami was followed for 2 years. Despite the recent introduction of nets in the Yanomami villages and the adverse natural conditions in the area, the nets were accepted enthusiastically by the study population, used conscientiously and looked after carefully. The malaria incidence rate per thousand person-years at risk was 114.6 in the IHTN group and 186.8 in the PTHN group. The adjusted rate ratios indicated that ITHN prevent 56% [IRR: 0.44, 95% confidence interval (CI): 52–59%] of new malaria cases. ITHN reduced the prevalence of parasitaemia by 83% [relative risks (RR): 0.17, 95% CI: 47–100%], according to a cross-sectional survey carried out during the high transmission season. The prevalence of splenomegaly and anaemia was too low to detect any possible reduction as a result of ITHN. The main conclusion of the present study is that ITHN can reduce malaria incidence in the area and it is the most feasible method for malaria control in a forested area where indigenous villages are scattered over a large territory. This is the first community-level epidemiological trial to show that ITHN are highly effective against malaria transmitted by Anopheles darlingi. [ABSTRACT FROM AUTHOR]

Abstract: An indoor vector control trial was carried out between December 1996 and February 1997, with the aimof reducing the population densities of Lutzomyia ovallesi, the proven vector of cutaneous leishmaniasis (CL) in El Ingenio, Miranda State, Venezuela. Houses were matched according to their structure (‘bahareque’ [mud and straw], concrete, and wood) and randomly assigned to a control group (n = 19) or a treated group (n = 20) that was sprayed with 25 mg/m2 of lambdacyhalothrin. This dose was selected on the basis of a laboratory susceptibility test of Lu. ovallesi to pyrethroids. Sandfly abundance was measured using CDC light traps 7–79 d post-intervention, by which time the sandfly population in control houses had declined to very low levels, at what was the end of the transmission season. Catches of total females, fed females, and males were significantly lower in sprayed than in control houses immediately after treatment. Catches of total females and males in sprayed houses recovered, reaching the level of control houses after 7 and 11 weeks, respectively. Bioassays following WHO protocols using contact cones on a sandfly laboratory colony showed a short residual effect of the insecticide explaining these results. In contrast, there was no tendency for catches of fed females in the sprayed houses to recover during the course of the trial. Previous studies of adult population dynamics showed a short season of high abundance. Combined with these results, we believe that 2 indoor sprayings with lambdacyhalothrin, the first at the beginning of November and the second at the beginning of January, would considerably reduce the Lu. ovallesi population, and control CL transmission in this and other foci where this sandfly is considered to be the main vector. [Copyright &y& Elsevier]

Abstract Background In Morocco, cutaneous leishmaniasis is transmitted by Phlebotomus sergenti and Ph. papatasi. Vector control is mainly based on environmental management but indoor residual spraying with synthetic pyrethroids is applied in many foci of Leishmania tropica. However, the levels and distribution of sandfly susceptibility to insecticides currently used has not been studied yet. Hence, this study was undertaken to establish the susceptibility status of Ph. sergenti and Ph. papatasi to lambdacyhalothrin, DDT and malathion. Methods The insecticide susceptibility status of Ph. sergenti and Ph. papatasi was assessed during 2011, following the standard WHO technique based on discriminating dosage. A series of twenty-five susceptibility tests were carried out on wild populations of Ph. sergenti and Ph. papatasi collected by CDC light traps from seven villages in six different provinces. Knockdown rates (KDT) were noted at 5 min intervals during the exposure to DDT and to lambdacyhalothrin. After one hour of exposure, sandflies were transferred to the observation tubes for 24 hours. After this period, mortality rate was calculated. Data were analyzed by Probit analysis program to determine the knockdown time 50% and 90% (KDT50 and KDT90) values. Results Study results showed that Ph.sergenti and Ph. papatasi were susceptible to all insecticides tested. Comparison of KDT values showed a clear difference between the insecticide knockdown effect in studied villages. This effect was lower in areas subject to high selective public health insecticide pressure in the framework of malaria or leishmaniasis control. Conclusion Phlebotomus sergenti and Ph. papatasi are susceptible to the insecticides tested in the seven studied villages but they showed a low knockdown effect in Azilal, Chichaoua and Settat. Therefore, a study of insecticide susceptibility of these vectors in other foci of leishmaniasis is recommended and the level of their susceptibility should be regularly monitored.