Assessment of the Endoparasite Fauna amongst the Rodents in Kurdistan Province, West of Iran.

Background: We aimed to evaluate the rate of infection by endoparasites amongst rodents in the western regions of Iran to enhance the level of knowledge amongst health authorities in this entity. Methods: This study was conducted in the west and southwest of Kurdistan Province, including the cities of Sanandaj, Marivan, and Sarvabad. The field mission of this work was performed in three seasons' spring, summer, and autumn. The rodents were captured alive and their gastrointestinal tracts were evaluated for the worm endoparasites. Results: Herein, 208 rodents from 15 types of seven species, including Apodemus, Meriones, Mus, Sciurus, Cricetulus, Microtus, and Dryomys, were captured. In addition, 67 (32.21%) rodents were infected with endoparasites and 10 types of worms endoparasites, including Syphacia muris, Streptophagus spp., Mastophorus muris, Skrjabinema spp., Trichostrongylus spp., Trichuris muris, Hymenolepis nana, Hymenolepis dimimuta, Heligmosomoide spp., and other oxiuros were isolated from their gastrointestinal tracts. Most of these parasites (60%) were isolated from their small intestine whereas they were least (10%) found in their stomach and cecum. Conclusion: Having compared the results of this study with other studies in different regions of Iran, there is a higher variety of rodents and worm parasites in these regions of Iran.

Situation of insecticide resistance in malaria vectors in the World Health Organization of Eastern Mediterranean region 1990-2020.

Malaria is the most important mosquito-borne disease, which is transmitted by Anopheles species. According to the recent report of World Health Organization, there were an estimated 229 million malaria cases in 2019 in 87 malaria endemic countries. There are several vector control method specially using pesticides. The aim of this study was to collect all the data about insecticide resistant of malaria vectors in the Eastern Mediterranean region countries. In this study, all the published papers related to insecticide resistance of malaria vectors in the region were collected and resistant status of vectors in the countries was mapped. Resistance to different insecticide classes such as pyrethroids, organophosphate, organochlorine and carbamates were evaluated using World Health Organization guidelines. Results showed a wide variety of susceptibility/resistance status to these chemicals according to the location, historical context of pesticide used, genetic background of vectors, age and abdominal conditions of adults may play a role in the susceptibility status of these species to different insecticides. The results of this study is providing a guideline for countries to manage their vector control activities against insecticide resistance of malaria vectors and provide novel approaches such as male sterility, using Wolbachia, using new insecticide with new mode of action.

Bioefficacy of bendiocarb WP80 in vector-borne and zoonotic diseases areas in borderline of Iran and Pakistan.

Malaria and leishmaniasis are the public health problems in southern Iran. The main activity of vector control is indoor residual spraying using pyrethroids, using different insecticides as larviciding and impregnated bednets. The aim of study was to evaluate the biological assays of bendiocarb wettable powder (WP) at different surfaces of wall. The residual effect of bendiocarb WP80 at 400 milligram/meter square (mg/m2) was evaluated on various local surfaces of rooms such as mud and plaster as well as thatch roofs and wooden. World Health Organization standard cones using contact bioassays were carried out using laboratory reared sugar-fed, 48-72 h old females of Anopheles stephensi. Contact bioassays were carried out on sprayed surfaces for 150 days. Contact bioassay on surfaces treated with bendiocarb WP80 at different surfaces was estimated about 2 months. Fumigant tests of bendiocarb WP80 at 400 mg/m2 revealed 50-93.83% mortality with 1 month persistency. The results showed that carbamate insecticide could be used as rotation with pyrethroids for malaria vector control. Monitoring and evaluation of environmental toxicology of pesticides is important for decision making for choosing appropriate pesticides for disease vector control.

Comparative Testing of Susceptibility Levels of Phlebotomus sergenti, the Main Vector of Anthroponotic Cutaneous Leishmaniasis, to Conventional Insecticides Using Two Capture Methods in Kerman City, Southeastern Iran.

BACKGROUND: Collecting live sand flies from indoor sites is a major challenge for researchers in large cities due to the reluctance of families to survey their homes. This study was conducted to assess the efficacy of two methods for collecting sand flies for use in susceptibility tests in the urban area of Kerman, southeastern Iran. METHODS: Sandflies were mainly collected using both baited traps and hand catch methods from outdoor and indoor sites. Susceptibility tests were separately done according to the standard World Health Organization testing protocol on Phlebotomus sergenti, including 60-minute exposure to DDT 4.0%, propoxur 0.1%, deltamethrin 0.05%, and malathion 5.0%. RESULTS: During this research, the natural habitats and suitable indoor sites were selected to predict the density of live sand fly with perfect accuracy. The number of live Ph. sergenti caught by hand catch and baited traps methods was 42 and 361 in indoor and outdoor sites, respectively. The mortality rate of Ph. sergenti exposed to DDT 4%, deltamethrin 0.05, malathion 5%, and propoxur was 100%. CONCLUSION: The baited traps showed a significant efficiency compared to hand catch for collecting live Ph. sergenti for use in susceptibility tests in urban areas. The Ph. sergenti collected from both indoor and outdoor sites were susceptible to all insecticides.

Relationship between Wolbachia infection in Culex quinquefasciatus and its resistance to insecticide.

Many studies have been done on the various factors affecting resistance to insecticides. The relationship between Wolbachia bacteria and resistance to insecticides is one of the factors that has attracted a lot of attentions. Wolbachia are obligatory intracellular endosymbionts that naturally occur in a wide range of arthropods and nematodes, including the mosquito Culex quinquefasciatus. Initially, the presence of bacteria was proved by molecular assays. Then the resistance level of this species was evaluated in adults against DDT 4.0% and deltamethrin 0.05% using the standard WHO guideline. After elimination of Wolbachia by tetracycline and its proof by molecular assays, the susceptibility tests were conducted again on uninfected line. Finally, the two lines were compared in terms of responding to insecticides. The findings indicated that there is no significant correlation between susceptibility of two lines in response to DDT 4.0% while they represented a significant correlation for deltamethrin (P =0.00). We propose that Wolbachia bacteria increase the susceptibility to deltamethrin but they show neutral effect on DDT susceptibility in Cx. quinquefasciatus. However, more studies on other vectors and insecticides still need to be done.

Detection and characterization of Enterobacteriaceae family members carried by commensal Rattus norvegicus from Tehran, Iran.

Wild rats are known to carry different microorganisms and are considered a reservoir of zoonotic pathogens worldwide. The urban rats were collected from five districts of Tehran and Gram-negative bacteria (GNB) were isolated from fecal samples and were identified using classical biochemical tests. The antibiotic susceptibility patterns of isolated bacteria were determined by Kirby-Bauer disk diffusion method, the results of which were interpreted in line with CLSI guideline. The frequency of antibiotic-resistant genes was identified using multiplex-PCR. Moreover, PCR method was used to identify the frequency of Escherichia coli O157:H7 and main categories of diarrheagenic E. coli including EPEC, ETEC, EIEC, EAEC, and STEC pathotypes. A total of 100 Rattus norvegicus were trapped and fecal samples were collected. Overall, 72 fecal samples were positive for GNB. E. coli (n = 46/72) had the highest frequency among the isolated GNB. Among E. coli isolates, the highest and lowest resistance rates belonged to ampicillin (56.5%) and ceftriaxone (0%), respectively. Klebsiella spp. was 100% resistant to imipenem, and streptomycin (0%) was the most effective antimicrobial agent on Klebsiella spp. Among surveyed genes, blaTEM (95.8%) and blaaadA-1 (58.3%) had the highest frequency, while blaKPC, and blaCMY-2 were not detected among Enterobacteriaceae. Herein, O157: H7 serotype was not detected and aEPEC (87%) was the most common pathotype detected. Results suggested that rodents might be a reservoir of antimicrobial-resistant pathogens and rodent control along with implementation of surveillance programs should be considered as a critical priority for urban health.

Resistance Status of Anopheles maculipennis and Anopheles superpictus to the Conventional Insecticides in Northeastern Caspian Littoral, Iran.

BACKGROUND: Malaria resurgence has occurred in the northern half parts of Iran. The resurgence of malaria in the prone area could arise from various factors, e.g. wide use of pesticides in the agriculture sector and factors such as habitual patterns of movement of local people from problematic southeastern foci in Iran toward the Caspian Littoral. There are no new data on the resistance status of main malaria vectors in the Caspian Littoral, and this study was aimed at renewal data on conventional insecticides. METHODS: The field strain of adult Anopheles superpictus and Anopheles maculipennis were collected using the hand catch method and transferred to the laboratory. The susceptibility tests were carried out against DDT 4%, Malathion 5%, Permethrin 0.75%, Deltamethrin 0.05%, and Lambda-cyhalothrin 0.05%, followed by the WHO's procedure. RESULTS: The primary malaria vector in Caspian Littoral is An. maculipennis, revealed to be still resistant to DDT and mortality rate, LT50 and LT90 of female mosquitoes were 75.0%, 54.2, minutes and 111.3 minutes. The under 'verification required' status of An. maculipennis was also revealed to Lambda-cyhalothrin based on recent WHO's criteria. The malaria vector An. superpictus is also considered the second malaria vectors in the west parts of the studied area, which showed to be susceptible to all insecticides tested. CONCLUSION: DDT resistance is persisted in An. maculipennis despite stopping residual spraying with DDT since 1978 in the Caspian Littoral, but the occurrence of pyrethroid under 'verification required' status is a progressive threat to the possible development of cross-resistance in the future.

Assessment the Changing Trend of Susceptibility to Two Insecticides among Field-Population Culex quinquefasciatus Compared with the Same Population Undergoing to Multiple Colonization.

BACKGROUND: During the past decade, rapid development of insecticide resistance have been reported among many species of mosquito vectors against four main categories of insecticides worldwide. The aim of the research was to assess the variation trend of susceptibility levels of Culex quinquefasciatus to two insecticides separately for the field population compared with subsequent generations of the same sample after multiple colonization. METHODS: Larvae and pupae of Cx. quinquefasciatus were collected from house sewages and reared to adult which blood-fed on roosters. Ten percent sucrose fed female mosquitoes aged 2-3 days were used for susceptibility tests with DDT and deltamethrin. Susceptibility levels was assessed in the adult stage of field stran Cx. quinquefasciatus against DDT 4.0% and deltamethrin 0.05% and continued up to next six generations undergoing multiple rearing at insectary condition. RESULTS: The susceptibility levels to DDT 4.0% did not change compared to the field with the lab population to six generations. Regarding deltamethrin 0.05%, no significant difference was shown between field strain (58.3%) and 3rd generation (52.7%) compared to the 6th one (33.8%). CONCLUSION: This finding may reflect the role of the kdr gene in resistance to organochlorine which has cross-resistance with pyrethroid insecticides. The results of this study clearly showed the irreversible trend of pyrethroid resistance among colonized mosquitoes. This is the first study of the resistance status of Cx. quinquefasciatus in Iran.

Mansonia uniformis (Diptera: Culicidae), a genus and species new to southwestern Asia, with a review of its medical and veterinary importance.

Seven genera and more than 98 species of mosquitoes (Diptera: Culicidae) are found in southwestern Asia (Harbach 1988). The most recent checklist of Iranian mosquitoes includes 69 species representing either seven or 11 genera depending on the classification used for aedines (Azari-Hamidian et al. 2019). Orthopodomyia pulcripalpis (Rondani) was the most recent genus and species to be added to the Iranian mosquito fauna (Azari-Hamidian et al. 2017).

Bio-efficacy of ultrasound exposure against immature stages of common house mosquitoes under laboratory conditions.

Purpose: In southern Iran with a tropical climate, the above and underground cisterns of drinking water are the main habitats for immature stages of mosquitoes. The local people do not agree with using calcium hypochlorite granules in the water cisterns due to the change of water taste. Following the increased worldwide interest in using ultrasound technology for water disinfection, this study was conducted to assess the possible dual effects of ultrasound waves against immature mosquitoes.Materials and methods: Combinations of four power levels, two frequencies, three temperatures, and eight exposure times were applied to immature Culex pipiens. The exposure chamber of immature mosquitoes was the disposable cups placed inside a sonication bath containing tap water.Results: The mortality rate of immature mosquitos was 85-91% at 10-25 W, 30 °C and 130 kHz. The most effective ultrasound regimen for causing immature mortality included a fixed frequency of 130 kHz, a temperature of 30 °C, and a power level of 20-25 W. The lowest efficacy was observed in the egg stage. The median lethal time (LT50) and ninety percent lethal time (LT90) of sonication was 5.9 ± 0.6 min and 1.6 ± 0.1 min at 30 °C and a fixed frequency of 130 kHz.Conclusions: Evidence indicated effective ultrasound irradiation against immature mosquitoes in the water. This study provides a clear scientific basis for larvicidal properties induced by ultrasound emissions at laboratory conditions. The findings could be used for setting the ultrasound devices in the field investigations for achieving desired effectiveness.

Wild Rodents and Their Ectoparasites in an Enzootic Plague Focus, Western Iran.

Introduction: Entomological surveys of ectoparasites and their hosts are an essential tool for assessing the risks of rodent-borne diseases transmitted to humans by arthropod vectors. Objectives: This study was carried out to update the epidemiological data of plague with respect to species compositions of the rodents and their ectoparasites at enzootic foci located in Kurdistan Province, Iran. Methods: The rodents' habitats were selected based on past records of plague and subclimates in each study district with especial attention to the vegetation type. The trapped rodents were anesthetized using a chloroform chamber, and the animals were then examined for ectoparasites by brushing their hair over a pan containing water. The ectoparasites were collected with a fine brush and preserved in 70% ethanol in screw cap tubes. Results: A total of 208 rodents were trapped from three districts. Taxonomic ranking of the rodents indicated that the specimens belonged to 2 suborders of Myomorpha and Sciuromorpha, 4 families (Muridae, Muscardinidae, Cricetidae, and Sciuridae), 7 genera, including Meriones, Apodemus, Mus, Sciurus, Microtus, and Dryomys, and 15 species. Out of 208 rodents, only 56 (26.9%) were infested with 22 species of ectoparasites. Totally, 312 ectoparasites were isolated from 56 rodents, including 12 flea species (54.5%), 6 mite species (27.3%), 3 tick species (13.6%), and one louse species (4.6%). Five species of fleas were recorded for the first time in Kurdistan Province, including Ctenophthalmus iranus persicus, Paraceras melis melis, Nosopsyllus iranus iranus, Paraceras sp., and Ctenophyllus spp. Conclusion: The finding revealed new records for rodents and ectoparasites in Kurdistan Province, as well as changes in dominant rodent species and their ectoparasites compared to previous studies. This phenomenon can influence the changes in the incidence of plague and its epidemiology.

Epidemiological survey on Cutaneous Leishmaniasis in southwestern Iran.

BACKGROUND & OBJECTIVES: Cutaneous leishmaniasis (CL) is still a public health threat in many rural areas of Iran. It causes considerable morbidity among a huge number of people in the endemic areas. Khuzestan is considered as a CL focus in Iran and recently several cases have been reported from Shush County. The aim of the current study was to determine different aspects of CL epidemiology in this County. METHODS: The study was conducted in four villages in the rural district of Shush County. In order to survey the scar and acute rate of the disease, 100 inhabitants were questioned in each village. In addition, to determine the reservoir host and vector of the disease, rodents were captured using Sherman traps, and sandflies were collected from around the rodent burrows using sticky paper traps. RESULTS: The scar and acute lesion rates were reported as 5.26 and 0.57% among inhabitants, respectively. Fifty-four rodents including Tatera indica (55.5%), Nesokia indica (33.3%), Mus musculus (9.3%) and Rattus norvegicus (1.9%) were captured and identified. Nested PCR showed 3 out of 54 rodents infected with Leishmania major. In total, 1122 sandflies were collected, and Leishmania major detected in Phlebotomus papatasi (4.35%), Sergentomyia dentata (23%), and Sergentomyia clydei (10%). INTERPRETATION & CONCLUSION: Zoonotic cutaneous leishmaniasis due to L. major prevailed in this area. The common and the main vector was Ph. papatasi and, T. indica seems to be the main while N. indica as a secondary reservoir host of the disease in this area.

Resistant status of Culex pipiens complex species to different imagicides in Tehran, Iran.

BACKGROUND & OBJECTIVES: Insecticides are the most important means of controlling pests in Iran especially for Culex pipiens complex species. The rational use of insecticides largely depends on understanding the susceptibility levels of these species. The study was designed to determine the susceptibility levels of Cx. pipiens complex (field and insectary strains) to various insecticides in the city of Tehran. METHODS: The mortality rates of the field strain of Cx. pipiens complex after different exposure times to DDT (4%), bendiocarb (0.1%), propoxur (0.1%), malathion (5%), fenitrothion (1.0%), permethrin (0.75%), deltamethrin (0.05%), lambda-cyhalothrin (0.05%), etofenprox (0.5%), and cyfluthrin (0.15%) were determined. The mortality rates at the lethal time 50% (LT50) and lethal time 90% (LT90) values were calculated by plotting the regression line using Microsoft Office Excel software. RESULTS: The mortality rates of the Cx. pipiens complex after 1 h exposure to the diagnostic doses of DDT (4%), bendiocarb (0.1%), propoxur (0.1%), malathion (5%), fenitrothion (1.0%), permethrin (0.75%), deltamethrin (0.05%), lambda-cyhalothrin (0.05%), etofenprox (0.5%), and cyfluthrin (0.15%) were 12, 58, 54, 82, 54, 34, 49, 40, 17, and 44%, respectively. According to the WHO classification of susceptibility levels, both field and insectary strains of Cx. pipiens complex in Tehran were resistant to these insecticides. INTERPRETATION & CONCLUSION: The results of this study showed that field Cx. pipiens complex is resistant to all the groups of insecticides used.

Efficiency of Two Capture Methods Providing Live Sand Flies and Assessment the Susceptibility Status of Phlebotomus papatasi (Diptera: Psychodidae) in the Foci of Cutaneous Leishmaniasis, Lorestan Province, Western Iran.

BACKGROUND: The aims of this study were to evaluate the efficiency of two capture methods for providing live sandflies used for determining the susceptibility level of Phlebotomus papatasi, the main vector of zoonotic cutaneous leishmaniasis in Lorestan Province, west of Iran. METHODS: The sand flies were collected from indoor and outdoor by hand-catch and baited traps during the peak of seasonal activity. The susceptibility level of sand flies was assessed using insecticide-impregnated papers against DDT 4%, bendiocarb 0.1%, permethrin 0.75%, deltamethrin 0.05%, and cyfluthrin 0.15%. RESULTS: A total of 2486 live sandflies were caught from both indoor and outdoor places. Totally 849 sand flies were caught from outdoors with a sex ratio(SR) 0.1 versus 1637 sand flies collected from indoor using the hand-catch method with SR= 0.6. The dominant species of sand flies was Ph. papatasi in the study area. Mortality rates of outdoor-collected sand flies were exposed to DDT 4%, deltamethrin 0.05%, permethrin 0.75%, and bendiocarb 0.1%, and mortality rate ranged from 92.0-97.9% and for indoor-collected sand flies were 87.7-96.8%. Both outdoor and indoor collected sand flies were susceptible to cyfluthrin 0.15% that caused 100% mortality. CONCLUSION: Based on the findings, the most appropriate method for collecting the live female Ph. papatasi is the baited traps due to providing enough females is necessary for conducting the susceptibility tests. The finding indicated that Ph. papatasi was resistant to DDT, under 'verification required' status to deltamethrin, permethrin, bendiocarb, and susceptible to cyfluthrin.

Using Ecological Niche Modeling to Predict the Spatial Distribution of Anopheles maculipennis s.l. and Culex theileri (Diptera: Culicidae) in Central Iran.

BACKGROUND: Mosquitoes are very important vectors of diseases to human. We aimed to establish the first spatial database on the mosquitoes of Isfahan Province, central Iran, and to predict the geographical distribution of species with medical importance. METHODS: Mosquito larvae were collected from eight counties of Isfahan Province during 2014. Collected data were transferred to a database in ArcGIS and the distribution maps were created. MaxEnt model and jackknife analysis were used to predict the geographical distribution of two medical important species, and to find the effective variables for each species. RESULTS: Totally, 1143 larvae were collected including 6 species, Anopheles maculipennis s.l., An. superpictus s.l., An. marteri, Culex hortensis, Cx. theileri and Culiseta longiareolata. The area under curve in MaxEnt model was 0.951 and 0.873 rather 1 for An. maculipennis s.l. and Cx. theileri, respectively. Culex theileri had wider and more appropriate niches across the province, except for the eastern area. The environmental variable with highest gain was mean temperature of the wettest quarter for Cx. theileri and temperature seasonality for An. maculipennis. Culex theileri, An. maculipennis s.l. and An. superpictus, three important vectors of parasitic agents to humans, were collected in this study. CONCLUSION: The mosquito collected and mapped can be considered for transmission of malaria and filariasis in the region. Bearing in mind the results of niche modeling for vector species, more studies on vectorial capacity and resistance status to different insecticides of these species are recommended.

Status of Resistant and Knockdown of West Nile Vector, Culex pipiens Complex to Different Pesticides in Iran.

BACKGROUND: West Nile virus (WNV) can cause a fatal disease in humans and it is mainly transmitted to people through the bites of infected mosquitoes. Vector control using insecticides is a very important goal. Study of Culex pipiens resistance towards several insecticides in the city of Tehran, Iran was evaluated. METHODS: Adult females reared from field-caught larvae from southern part of Tehran and lab strain reared in the insectary of Tehran University of Medical Science were determined for resistant status by exposing to 4% DDT, 0.1% bendiocarb, 0.1% propoxur, 1% fenitrothion, 0.05% deltamethrin, 0.75% permethrin, 0.05% lambda-cyhalothrin, 0.5% etofenprox, 5% malathion and 0.15% cyfluthrin papers using the standard WHO susceptibility tests. RESULTS: Results clearly showed resistance development of Cx. pipiens against tested insecticides. Mortalities of Cx. pipiens were less than 90% with high resistance, low knock down rate and knock down time (50%) observed against insecticides. DDT and Malathion showed the most and least lethal time (LT50) values for the field strain. The results of the knockdown test showed that DDT and deltamethrin had the most and least knockdown times (50%) for the field strain, respectively, while DDT and lambda-cyhalothrin had the most and least knockdown times (50%) for the lab strain, respectively. CONCLUSION: Resistance to mentioned insecticides in Cx. pipiens is widely distributed in southern part of Tehran. Regular implementation of susceptibility test in Cx. pipiens mosquitoes will help local public health authorities to develop new and better control strategies.

Prone Regions of Zoonotic Cutaneous Leishmaniasis in Southwest of Iran: Combination of Hierarchical Decision Model (AHP) and GIS.

BACKGROUND: Cutaneous leishmaniasis due to Leishmania major is an important public health problem in the world. Khuzestan Province is one of the main foci of zoonotic cutaneous leishmaniasis (ZCL) in the southwest of Iran. We aimed to predict the spatial distribution of the vector and reservoir(s) of ZCL using decision-making tool and to prepare risk map of the disease using integrative GIS, RS and AHP methods in endemic foci in Shush (plain area) and Khorramshahr (coastal area) counties of Khuzestan Province, southern Iran from Mar 2012 to Jan 2013. METHODS: Thirteen criteria including temperature, relative humidity, rainfall, soil texture, soil organic matter, soil pH, soil moisture, altitude, land cover, land use, underground water depth, distance from river, slope and distance from human dwelling with the highest chance of the presence of the main vector and reservoir of the disease were chosen for this study. Weights of the criteria classes were determined using the Expert choice 11 software. The presence probability maps of the vector and reservoir of the disease were prepared with the combination of AHP method and Arc GIS 9.3. RESULTS: Based on the maps derived from the AHP model, in Khorramshahr study area, the highest probability of ZCL is predicted in Gharb Karoon rural district. The presence probability of ZCL was high in Hossein Abad and Benmoala rural districts in the northeast of Shush. CONCLUSION: Prediction maps of ZCL distribution pattern provide valuable information which can guide policy makers and health authorities to be precise in making appropriate decisions before occurrence of a possible disease outbreak.

Comparison of CDC Bottle Bioassay with WHO Standard Method for Assessment Susceptibility Level of Malaria Vector, Anopheles stephensi to Three Imagicides.

BACKGROUND: The detection of insecticide resistance in natural populations of Anopheles vectors is absolutely necessary for malaria control. CDC bottle bioassay as a new tools has been employed for detecting the insecticide resistance. For a limit number of mosquito vectors, diagnostic doses and diagnostic times for some insecticides have already been determined using this new assay. For the first time in the area, susceptibility levels of Anopheles stephensi was done with DDT, deltamethrin, and bendiocarb using CDC bottle bioassay and compared results with WHO standard test method. METHODS: Anopheles stephensi were collected in larvae stage from the cisterns of drinking water in Chabahar port which considered as old malaria foci, Sistan and Baluchistan province. The field collected larvae were colonized at the insectary of School of Public Health (SPH), Tehran University of Medical Science. The susceptibility tests were carried out on sugar fed female mosquitoes aged 2-3 days, against DDT 4%, bendiocarb 1% and deltamethrin 0.05% using WHO and CDC susceptibility methods. The mortality and knockdown rates, as well as the parameters of regression analysis, including LT50 and LT90, was calculated separately for the WHO and CDC methods. RESULTS: The 24h mortality rates of An. stephensi were 28.6% and 25.6% for DDT, 60.8% and 64.6% for bendiocarb and 100% for deltamethrin using both WHO and CDC assay at 30 and 60min respectively. The 50% lethal times (LT50) were estimated 44.9 and 66.2min, 38.9 and 81.8min and 0.7 and 15.0min respectively using both WHO and CDC susceptibility tests. CONCLUSION: The similar results of susceptibility levels were shown for DDT, bendiocarb and deltamethrin. The lethal times (LT50) showed significant difference using both WHO and CDC bioassay methods.

Target Site Insensitivity Detection in Deltamethrin Resistant Culex pipiens Complex in Iran.

BACKGROUND: Some mosquito species which belong to the Culex. pipiens complex are primary vectors for West Nile virus, Sindbis, Dirofilaria immitis, and many arboviruses. Knockdown resistance (kdr) mutations in the voltage-gated sodium channel (VGSC) gene of Cx. pipiens that is inherited, is one of the important threats for the efficacy of pyrethroids insecticides. Knockdown resistance (kdr) mutation, L1014F, is a well-defined mechanism of resistance to pyrethroids and DDT in many insect species. The aim of study was to determine the mechanisms of Insecticide resistance in this species. METHODS: Specimens of Cx. pipiens, the major vector of West Nile virus, were obtained in Tehran, Iran by collecting larvae from polluted wastewater in Qarchak of Tehran. In 2016 Insecticide susceptibility tests were performed according to WHO methods with deltamethrin 0.05%. We focused on determination of this point mutation in the VGSC gene of Cx. pipiens by Real-time PCR. RESULTS: Our results revealed high levels of resistance to deltamethrin 0.05%. The lethal times i.e. LT50 and LT90 for deltamethrin were 2.1530 and 8.5117 h respectively. The result of Real-time PCR confirmed the presence of resistant genotype in all the members of tested population. This study is the first report on kdr genotyping of Cx. pipiens from Tehran and our results on the VGSC gene in position L1014F confirmed the TTA to TTT nucleotide change. CONCLUSION: This finding will provide a clue for management of insecticide resistance in mosquito which are vectors of arboviruses and decision for replacement of novel approach for vector control.

Identification of Forensically Important Flesh Flies Using the Cytochrome C Oxidase Subunits I and II Genes.

Forensically important flesh flies (Diptera: Sarcophagidae) often are not morphologically distinguishable, especially at the immature stage. In addition, female flies are quite similar in general morphology, making accurate identifications difficult. DNA-based technologies, particularly mitochondrial DNA (mtDNA), have been used for species-level identification. The cytochrome oxidase subunits I and II (COI-COII) sequences of Iranian Sarcophagidae are still unavailable in GenBank. In this study as many as 648 (540 males and 106 females) fly specimens from family Sarcophagidae, representing 10 sarcophagid species, including eight forensically important species were collected from seven locations in five Iranian provinces. Of these, 150 male specimens were identified based on both morphology of male genitalia and DNA sequencing analysis. Sequence data from the COI-COII regions for 10 flesh fly species collected in Iran were generated for the first time. Digestion of COI-COII region by restriction enzymes RsaI, EcoRV, and HinfI provided distinct restriction fragment length polymorphism profiles among the species and can serve as molecular markers for species determination. Phylogenetic analysis represented that the COI-COII sequences are helpful for delimitation of sarcophagid species and implementation in forensic entomology. However, the application of the COI-COII fragment as a species identifier requires great caution and additional species and markers should be studied to ensure accurate species identification in the future.