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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: Myiasis is a disease caused by infections of tissues and organs of human and vertebrates body by the larvae of real flies of Diptera which feeding on living or dead tissues of host for a period of time. This report aims to present a case of urogenital myiasis caused by the larvae of Psychoda albipennis (Diptera: Psychodidae) for the first time in Iran. Methods: In this case report, we present a case of a 9-year-old girl with urogenital myiasis caused by P. albipennis. She presented to Sina Hospital with dysuria and claimed that he had observed several black-grayish colored mobile particles in his urine at different times. The patient lived in Miandoab, West Azerbaijan Province, Iran. Results: In the hospital her urine sample, containing 3 larvae was referred to Entomology lab of the Medical Faculty for identification and characterization. According to morphological factors, the larvae were identified to approximate size of 8–10mm long, white to gray color, thorns and pale scales and a siphon at the posterior end of the body. By comparing the larvae with the reported ones from Turkey, diagnosis was confirmed. Conclusions: According to our survey, this is the first observation of urogenital myiasis in East Azerbaijan Province, Iran. Our case illustrates urogenital myiasis caused by P. albipennis in Iran. Urogenital myiasis has not been previously reported from Iran as a human disease. [ABSTRACT FROM AUTHOR]

Background:Ticks are vectors of a wide variety of pathogens that can be transmitted to humans, and tick-borne diseases are a significant public health issue worldwide. The present study was carried out on the hard tick infestation of live-stock transported to Rafsanjan slaughter house in the southeast of Iran. Methods: A cross-sectional survey was carried out biweekly from April to September 2016 to determine tick infestation of the meat-producing animals. All the livestock included in our study were thoroughly inspected for the presence of hard ticks on different parts of their bodies. Results: A total of 258 hard ticks were collected from the body of livestock hosts. The ticks that were sampled were classified into two genera and five species: Hyalomma marginatum, Hy. anatolicum,Hy. asiaticum, Hy. dromedarii, and Rhipicephalus sanguineus. Hyalomma dromedarii was the most abundant species in the study area. More than 50 per-cent of the sampled ticks were collected from the body of camels brought to the slaughter house however molecular analysis showed no Crimean Congo Hemorrhagic Fever (CCHF) virus infection in tick specimens.The Sex ratio of the sampled hard ticks shows that female tick infestation was more common among the study livestock. Conclusion: Due to the crucial role of hard ticks in the transmission of different pathogens to humans, additional investigations are necessary to determine the risk of consumption of infested meat-producing animals in the study area. [ABSTRACT FROM AUTHOR]

Objective: To determine the diversity of sand flies in different biotopes of mountainous and plain areas of Bam County as the most infected focus of anthroponotic cutaneous leishmaniasis in southeast Iran, and synanthropic index of Phlebotomus sergenti Parrot, and Phlebotomus papatasi Scopoli as the main vectors of cutaneous leishmaniasis in Iran. Methods: Sand flies were captured once a month using sticky traps in domestic, peri-domestic, agricultural, and sylvatic biotopes in the plain and mountainous areas. Alpha diversity indices, including richness, evenness, Shannon-Wiener; beta diversity indices (Jaccard's and Sorensen's similarity indices) and synanthropic index were calculated. Results: A total of 2 664 specimens of 9 sand fly species were collected from mountainous (47%) and plain (53%) areas. Species richness, species evenness, and Shannon-Wiener indices were obtained as 9, 0.637, and 1.399, respectively in the mountainous area. Phlebotomus sergenti and Phlebotomus papatasi were constant species with the synanthropic index of -18.463 and -29.412, respectively. In addition, species richness, species evenness, and Shannon-Wiener indices were 4, 0.690, and 0.956, respectively in the plain area. Phlebotomus sergenti and Phlebotomus papatasi were dominant species with the synanthropic index of +9.695 and +36.207, respectively. Similarity indices were low among different biotopes of plain and mountainous areas. Conclusions: A basic knowledge about the diversity of sand flies in various biotopes is essential to design sound control programs. Biodiversity and synanthropic indices of sand flies are different in plain and mountainous areas due to the difference in biotic and abiotic factors between the two areas. [ABSTRACT FROM AUTHOR]

Objective: To assess the chemical composition and mosquito larvicidal potentials of essential oil of wild chive (Allium schoenoprasum L.) against Anopheles stephensi. Methods: In the search for an environmentally safer alternative mosquitoes control, the larvicidal efficacy of essential oil obtained from the leaves of Allium schoenoprasum L. against Anopheles stephensi was determined. The composition of chive essential oil was analyzed by gas chromatography-mass spectrometry. Results: In toxicity assays, the essential oil demonstrated substantial larvicidal activity against larvae of Anopheles stephensi with LC50 and LC90 values of 2.60, and 7.31 ppm after 24 h of exposure, respectively. Gas chromatography-mass spectrometry analysis of chive essential oil identified 35 components representing more than 97.31% of the total essential oil. The main constituents were sulfur compounds, including diallyl trisulfide (13.72%), 2-ethyl[1,3]dithiane (8.93%), allyl methyl trisulfide (8.77%), and trimethylene trisulfide (6.64%), respectively. Conclusions: This study demonstrated that wild chive essential oil has a rich source of eco-friendly bioactive compounds for use as a mosquito larvicide. The main reason for its extraordinary properties may be related to the high percentage of sulfur compounds. [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: 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]

Background: Culiseta longiareolata is an important vector for many human diseases such as brucellosis, avian influenza and West Nile encephalitis. It is likely an intermediate host of avian Plasmodium that can transmit Malta fever. The aim of this study was to determine the susceptibility level of Cs. longiareolata to different classes of imagicides which are recommended by World Health Organization ., Methods: Larval stages of the Cs. longiareolata were collected from their natural habitats in Marand County at East Azerbaijan Province, northwestern of Iran in 2017. Adult susceptibility test were carried out with using impregnated papers to insecticides including DDT 4%, Cyfluthrin 0.15%, Deltamethrin 0.05%, Propoxur 0.1% and Fenitrothion 1% by standard test kits., Results: Results showed that Cs. longiareolata adult is more susceptible to pyrethroid and carbamate insecticides. Among tested insecticides, Cyfluthrin was the most toxic against Cs. longiareolata with LT 50 value of 11.53 minutes and Fenitrothion had the least toxic effect (LT 50 : 63.39 min)., Conclusions: This study provided a guideline for monitoring and evaluation of insecticide susceptibility tests against Cs. longiareolata mosquitoes for further decision making., (Copyright© Iranian Society of Medical Entomology & Tehran University of Medical Sciences.)