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Background: Kerman Province is one of the endemic foci of scorpionism in southeastern Iran. Totally 17 species are reported for Kerman Province fauna. The current study seeks to determine the fauna of medically important scorpions in northern parts of this province. Methods: A descriptive cross-sectional study was conducted from January 2019 to March 2021. The specimens were captured from different areas, by rock-rolling during day and using Ultraviolet light at night. The specimens were preserved in ethanol (80%) and then identified using reliable identification keys for scorpions. Results: Totally, 499 specimens were captured from eight cities in northern Kerman. In total, 11 species belonging to three families were identified. Buthacus sp. is reported for the first time from Kerman Province. Buthacus sp., Hottentotta cf. juliae, and Hottentotta cf. schach, were the lowest in frequency of occurrence, against Mesobuthus navidpouri as the highest frequency. Conclusion: The results of this study are useful for the preparation of regional or monovalent antivenom for the Razi Vaccine and Serum Research Institute. Additionally, the obtained data are useful for the effective planning of scorpion control programs in the northern parts of Kerman Province, Iran. [ABSTRACT FROM AUTHOR]

Background: Mosquitos due to their role in the transmission of different pathogens to humans are considered as an important group in the phylum Arthropoda. According to the WHO and FAO guideline different groups of insecticide applied for controlling pests in both the agricultural and public health sectors. Methods: All the data published about resistant status of the mosquitoes Anopheles, Culex, Aedes and Culiseta species were searched on PubMed, Elsevier, Web of Science, Magiran and google scholar. The objectives of this study was to review the trend of resistance to insecticides during 2000–2020 in medically important mosquitoes in Iran. The criteria for resistant are followed according to WHO guideline. Results: The Results showed that there are widespread, multiple resistances in the country to different organochlorine, organophosphates, carbamate and pyrethroids insecticides in the mosquitoes. Conclusion: The effect of pesticide residues on the environment could be a cause for selection pressure on mosquitos and lead to insecticides resistance to them. Insecticides resistance is main challenge of the vector control program. Also result will provide a guideline for control of the mosquito-borne diseases in the country as well as the world. [ABSTRACT FROM AUTHOR]

Background: Anopheles stephensi is a key urban malaria vector in the Indian subcontinent and Middle East including south and southeast of Iran. Wide application of insecticides resulted in resistance of this species to various insecticides in these regions. This study was conducted to reveal the role of metabolic mechanisms in the development of resistance in An. stephensi to DDT and cyfluthrin. Methods: Field mosquito specimens were collected from Chabahar Seaport, southeast corner of Iran, in 2015. Insecticide susceptibility and enzyme assays were conducted as recommended by WHO. Results: Mean enzyme ratios were 3.95 and 3.04 for α- esterases and 2.40 and 1.97 for β- esterases in the DDT and cyfluthrin- resistant populations correspondingly compared with the susceptible strain. The GSTs enzyme mean activity ratios were 5.07 and 2.55 in the DDT and cyfluthrin- resistant populations compared with the susceptible beech strain. The cytochrome p450s enzyme ratios were 1.11 and 1.28 in the DDT and cyfluthrin- resistant populations respectively compared with the susceptible beech strain. Conclusion: Metabolic mechanisms play a crucial role in the development of DDT and cyfluthrin resistance in An. stephensi, therefore, further evaluation of the mechanisms involved as well as implementation of proper insecticide resistance management strategies are recommended. [ABSTRACT FROM AUTHOR]

Background: Culex quinquefasciatus (Diptera: Culicidae) is an important vector for many human diseases. The aim of this study was to evaluate the susceptibility level of larval and adult stages of Cu. quinquefasciatus to different groups of WHO recommended insecticides for vector control. Methods: Larval stages of the Culex mosquitoes were collected from their natural habitats in Rafsanjan County at Kerman Province, southeast of Iran in 2016. Insecticide susceptibility status of adult female Cx. quinquefasciatus against DDT (4%), deltamethrin (0.05%), malathion 5%, and bendiocarb (0.1%) were determined using WHO standard insecticide susceptibility test. Additional test was carried out to determine the susceptibility status of larvae of Cx. quinquefasciatus to temephos. Bioassay data were analyzed by Probit program. Results: Cx. quinquefasciatus adults showed resistance to all four groups of the tested insecticides according to the WHO criteria for resistance evaluation. The lethal concentrations for 50% mortality (LC50) and 90% mortality (LC90) of temephos against Cx. quinquefasciatus larvae were 0.18mg/l and 0.78mg/l, respectively. This finding also confirms resistance to temephos based on the WHO recommended instructions for resistance evaluation. Conclusion: Resistance to all groups of the tested insecticides should be considered for future vector control investigations in the study area. [ABSTRACT FROM AUTHOR]

Background: Mosquitoes are responsible for the transmission of many pathogens and parasites and consequently serious diseases in humans. Currently, application of plant derivatives has been suggested as an alternative bio-control technique for these medically important vectors. Methods: In this study the essential oil and methanol extract of Achillea wilhelmsii were tested against late-3rd or young-4th instar larvae stages of mosquito vector, Anopheles stephensi, under laboratory condition. The larval mortality was calculated after 24 h of the exposure period. Data were subjected to Probit analysis in order to estimate the lethal concentration for 50% and 90% of mortality values. Results: Results showed that the essential oil induced 100% larval mortality of An. stephensi larvae after 24 h with a dosage of 160 ppm, However, a dosage of 320 ppm of methanol extract was required to reach 100% larval mortality.The essential oil methanol extract exerted significant larvicidal activity with LC50 values of 39.04 and 115.73 ppm, respectively. Conclusion: Our finding suggests that A. wilhelmsii oil is a potential source and has valuable larvicidal compounds for mosquito larval control. [ABSTRACT FROM AUTHOR]

Background: Anopheles mosquitoes are an important group of arthropods due to their role in transmission of malaria. The present study was conducted for determination of susceptibility status of Anopheles stephensi to different imagicides collected from malarious area in Chabahar city, Iran. Methods: In the present study seven insecticides including: DDT 4%, lambdacyhalothrin 0.05%, deltamethrin 0.05%, permethrin 0.75%, cyfluthrin 0.15% and etofenprox 0.5% were tested based on WHO method. Regression line was plotted for each insecticide using mortality of different exposure times. Bioassay data were analyzed using Probit software and the lethal time for 50% and 90% mortality (LT50 and LT90) values were calculated. Results: The susceptibility levels of field strain of An. stephensi to the discriminative dose of different imagicides were determined 100, 98, 96, 89, 82 and 62% for etofenprox, permethrin, deltamethrin, lambdacyhalothrin, cyfluthrin and DDT, respectively. Our finding indicated that An. stephensi is resistant to DDT, lambdacyhalothrin and cyfluthrin, and susceptible to etofenprox and permethrin and candidate of resistant to deltamethrin based on WHO criteria. Conclusion: Our findings indicated that An. stephensi is resistant to DDT and some pyrethroid insecticides which can be developed due to application of insecticides in health and agriculture. These results can provide a clue for future chemical control program in the study area. [ABSTRACT FROM AUTHOR]

Background: During recent years transmission of Dirofilaria immitis (dog heart worm) by Culex pipiens and West Nile virus have been reported from Iran. The present study was preformed for evaluating the susceptibility status of Cx. pipiens collected from capital city of Tehran, Iran. Methods: Four Insecticides including: DDT 4%, Lambdacyhalothrin 0.05%, Deltamethrin 0.05% and Cyfluthrin 0.15 % according to WHO standard methods were used for evaluating the susceptibility status of Cx. pipiens from Tehran moreover For comparison susceptibility status a Laboratory strain also was used. Bioassay data were analyzed using Probit program. The lethal time for 50% and 90% mortality (LT50 and LT90) values were calculated from regression line. Results: The susceptibility status of lab strain of Cx. pipiens revealed that it is susceptible to Lambdacyhalothrin, Deltamethrin, Cyfluthrin and resistant to DDT. Moreover cyfluthrin with LT50=36 seconds and DDT with LT50=3005 seconds had the least and most LT50s. Field population was resistance to all tested insecticides and DDT yielded no mortality. Conclusion: Highly resistance level against all WHO recommended imagicides were detected in field populations. We suggest more biochemical and molecular investigations to detect resistance mechanisms in the field population for further decision of vector control. [ABSTRACT FROM AUTHOR]

Background: Insecticide resistance is one of the serious problems for German cockroach control program. This study was conducted to determine the bendiocarb and Carbaryl resistance mechanisms in German cockroaches using the piperonyl butoxide (PBO). Methods: Bioassay tests were conducted with 4 to 6 different concentrations of both insecticides with four replicates of 10 susceptible strain cockroaches per concentration to determine of discriminative concentration. After determining discriminative concentration, the result was compared to wild strain. The levels of susceptibility and resistance ratio (RR) and synergism ratio (SR) were calculated for each five wild strains. Moreover resistance mechanisms in wild strains were determined using PBO synergist in vivo. Results: Hospital strains showed different levels of resistance to bendiocarb and carbaryl compared to susceptible strain. The bendiocarb and carbaryl resistance ratios ranged from 2.11 to 7.97 and 1.67 to 2 at LD50 levels, respectively. The synergist PBO significantly enhanced the toxicity of bendiocarb and carbaryl to all strains with different degrees of synergist ratio, 1.31, 1.39, 3.61, 1.78, 1.62 and 2.1 fold for bendiocarb, 1.19, 1.18, 1.12. 1.29, 1.45 and 1.11- fold for carbaryl, suggesting monooxygenase involvement in bendiocarb and carbaryl resistance. Conclusion: The synergetic effect of PBO had the highest effect on bendiocarb and resistance level was significantly reduced, which indicates the important role of monoxidase enzyme in creating resistance to Bendiocarb. Piperonyl butoxide did not have a significant synergistic effect on carbaryl and did not significantly break the resistance. [ABSTRACT FROM AUTHOR]