First report on the molecular phylogenetics and population genetics of Aedes aegypti in Iran.

BACKGROUND: Aedes aegypti, the primary vector of various human arboviral diseases, is a significant public health threat. Aedes aegypti was detected in Iran in 2018, in Hormozgan province, but comprehensive information regarding its genetic diversity and origin within the country remains scarce. This study aimed to determine the origin and genetic diversity of Ae. aegypti in southern Iran. METHODS: Aedes aegypti mosquitoes were collected from Bandar Abbas City, Hormozgan Province, southern Iran, between May and July 2022. Specimens were morphologically identified. Origin and assess genetic diversity were assessed based on the mitochondrial DNA-encoded cytochrome c oxidase subunit I (mtDNA-COI) gene. RESULTS: BLAST (basic local alignment search tool) analysis confirmed the accuracy of the morphological identification of all specimens as Ae. aegypti, with 100% similarity to GenBank sequences. Calculated variance and haplotype diversity were 0.502 and 0.00157, respectively. Among the 604 examined nucleotide sequences, only a single site was non-synonymous. Total nucleotide diversity and average pairwise nucleotides were determined as 0.00083 and 0.502, respectively. Fu and Li's D test values were not statistically significant. Strobeck's S statistic value was 0.487, and Tajima's D value was 1.53395; both were not statistically significant (P > 0.10). CONCLUSIONS: Phylogenetic analysis revealed two distinct clades with minimal nucleotide differences and low haplotype diversity, suggesting the recent establishment of Ae. Aegypti in the southern region of Iran. The phylogenetic analysis also indicated an association between Ae. aegypti populations and mosquitoes from Saudi Arabia and Pakistan.

Promising Larvicidal Effects of Nanoliposomes Containing Carvone and Mentha spicata and Tanacetum balsamita Essential Oils Against Anopheles stephensi.

PURPOSE: The use of synthetic pesticides to control the spread of mosquito-borne diseases has caused environmental pollution and insecticide resistance in mosquitoes. Developments of new green insecticides have thus received more attention to overcome these problems. METHODS: Nanoliposomes containing carvone and essential oils were first prepared. The nanoliposome physicochemical characteristics (particle size, morphology, and successful loading) were then evaluated by Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM), and the Attenuated Total Reflection-Fourier Transform InfraRed (ATR-FTIR) analyses. Larvicidal effects of carvone, Mentha spicata, and Tanacetum balsamita essential oils were investigated against the main malaria vector, Anopheles stephensi, in non-formulated and nanoformulated states. RESULTS: The larvicidal effects of nanoformulated states were significantly more potent (7.2 folds, 3.5 folds, and 8 folds) than non-formulated states. Nanoliposomes containing M. spicata and T. balsamita essential oils with particle sizes of 175 ± 8 and 184 ± 5 nm showed the best efficacies (LC50 values = 9.74 and 9.36 µg/mL). CONCLUSION: The prepared samples could be used as new green potent larvicides against An stephensi mosquito in further field trials. It is also recommended to investigate their efficacies against other mosquitoes.

Repellent efficacy of the nanogel containing Acroptilon repens essential oil in comparison with DEET against Anopheles stephensi.

OBJECTIVE: Malaria is a vector-borne disease that causes many deaths worldwide; repellents are a practical approach to malaria prevention, especially in endemic regions. RESULTS: Gas chromatography-mass spectrometry analysis was used to identify compounds in Acroptilon repens essential oil (EO). Alpha-copaene (15.67%), α-cubenen (3.76%), caryophyllene oxide (14.00%), 1-heptadecane (5.61%), and δ-cadinene (2.84) were five major compounds. After that, the nanoemulsion containing the EO with a particle size of 46 ± 4 nm, SPAN 0.85, PDI 0.4, and zeta potential - 5.7 ± 0.4 mV was prepared. Then, it was gellified by adding CMC (carboxymethyl cellulose) to the nanoemulsion. Besides, ATR-FTIR analysis (Attenuated Total Reflection-Fourier Transform InfraRed) was used to confirm the EO's successful loading in the nanogel. Finally, the protection time and repellent activity of nanogel compared to DEET (N, N-diethyl-meta-toluamide) were investigated against Anopheles stephensi. Interestingly, the nanogel with a protection time of 310 ± 45 min was significantly more potent than DEET (160 ± 17 min). It could thus be considered for future investigation against other mosquitoes.

Nanoliposomes containing three essential oils from the Artemisia genus as effective larvicides against Aedes aegypti and Anopheles stephensi.

Aedes aegypti and Anopheles stephensi have challenged human health by transmitting several infectious disease agents, such as malaria, dengue fever, and yellow fever. Larvicides, especially in endemic regions, is an effective approach to the control of mosquito-borne diseases. In this study, the composition of three essential oil from the Artemisia L. family was analyzed by Gas Chromatography-Mass Spectrometry. Afterward, nanoliposomes containing essential oils of A. annua, A. dracunculus, and A. sieberi with particle sizes of 137 ± 5, 151 ± 6, and 92 ± 5 nm were prepared. Besides, their zeta potential values were obtained at 32 ± 0.5, 32 ± 0.6, and 43 ± 1.7 mV. ATR-FTIR analysis (Attenuated Total Reflection-Fourier Transform InfraRed) confirmed the successful loading of the essential oils. Moreover, The LC50 values of nanoliposomes against Ae. aegypti larvae were 34, 151, and 197 µg/mL. These values for An.stephensi were obtained as 23 and 90, and 140 µg/mL, respectively. The results revealed that nanoliposomes containing A. dracunculus exerted the highest potential larvicidal effect against Ae. aegypti and An. stephensi, which can be considered against other mosquitoes.

Nanogels Containing Foeniculum vulgare Mill. and Mentha piperita L. Essential Oils: Mosquitoes' Repellent Activity and Antibacterial Effect.

Foeniculum vulgare Mill. and Mentha piperita L. are two common medicinally important plants with a wide range of biological activities such as insecticide and antibacterial effects. In this study, the chemical composition of their essential oils was investigated using GC-MS analysis. After that, their nanoemulsions were prepared; optimum samples with droplet sizes of 74 ± 7 and 136 ± 5 nm were gelified. The viscosity of the prepared nanogels and the successful loading of the essential oil in them were investigated. The efficacy of the nanogel containing M. piperita essential oil as a repellent and antibacterial agent was more potent than the nanogel containing F. vulgare essential oil. Its completely protected time against Anopheles stephensi, the main malaria mosquito vector, was 120 ± 8 min. Moreover, the growth of Escherichia coli and Staphylococcus aureus after treatment with 5000 µg/mL of nanogel containing M. piperita essential oil was reduced by 100 and 65%, respectively. Considering natural constituents, a straightforward preparation method, and high efficacy, the nanogel containing M. piperita essential oil could be introduced for further investigation against other mosquitoes and bacterial species.

Promising Larvicidal Efficacy of Solid Lipid Nanoparticles Containing Mentha longifolia L., Mentha pulegium L., and Zataria multiflora Boiss. Essential Oils Against the Main Malaria Vector, Anopheles stephensi Liston.

PURPOSE: An attempt was made in the current study to develop a natural mosquito larvicide using nanotechnology. METHODS: Solid lipid nanoparticles (SLNs) containing three essential oils were first prepared using the high-pressure homogenizer. Larvicidal effects of essential oils and the SLNs against Anopheles stephensi were then compared. RESULTS: The size of SLN containing Mentha longifolia, Mentha pulegium, Zataria multiflora essential oil was obtained as 105 ± 7, 210 ± 4, and 137 ± 8 nm. Their zeta potentials were - 7.8, - 4.7, and - 9.7 mV. Besides, their efficacy with LC50 values of 24.79, 5.11, and 9.19 µg/mL was significantly more potent than that of their un-formulated essential oils with LC50 values of 36.2, 27.55, and 33.33 µg/mL. CONCLUSION: SLNs containing M. pulegium with the best efficacy (P < 0.05) could be considered as potent larvicides against other important species of mosquitoes and field trials.

Nanoliposomes containing limonene and limonene-rich essential oils as novel larvicides against malaria and filariasis mosquito vectors.

BACKGROUND: Mosquito-borne diseases such as malaria and encephalitis are still the cause of several hundred thousand deaths annually. The excessive use of chemical insecticides for transmission control has led to environmental pollution and widespread resistance in mosquitoes. Botanical insecticides' efficacies improvement has thus received considerable attention recently. METHODS: The larvicidal effects of three essential oils from the Citrus family and limonene (their major ingredient) were first investigated against malaria and filariasis mosquito vectors. An attempt was then made to improve their efficacies by preparing nanoliposomes containing each of them. RESULTS: The larvicidal effect of nanoformulated forms was more effective than non-formulated states. Nanoliposomes containing Citrus aurantium essential oil with a particle size of 52 ± 4 nm showed the best larvicidal activity (LC50 and LC90 values) against Anopheles stephensi (6.63 and 12.29 µg/mL) and Culex quinquefasciatus (4.9 and 16.4 µg/mL). CONCLUSION: Due to the green constituents and high efficacy of nanoliposomes containing C. aurantium essential oil, it could be considered for further investigation against other mosquitoes' populations and field trials.

Baseline susceptibility of a wild strain of main vectors of leishmaniasis to WHO-recommended insecticides in southeastern Iran.

BACKGROUND: In Iran, both cutaneous leishmaniases (CL) and visceral leishmaniases (VL) are endemic, recording one of the 10 highest CL prevalence in the world. Parasites are transmitted by the bite of infected Phlebotomus sand fly females. Several sand fly species have been identified as vectors in the studied region of Kerman province. Residual spraying to control adult sand flies, is the only way to decrease the spreading of the diseases but, following control treatment against malaria vectors in endemic areas in Iran, resistance or tolerance to insecticides emerged in some sand fly species. The objective of this study was to survey insecticides susceptibility levels of 3 vector species in wild sand fly populations in different foci of the diseases in Kerman province. Ph. sergenti, and Ph. papatasi respectively vectors of anthroponotic and zoonotic cutaneous leishmaniases and for the first time Ph. alexandri one of the anthroponotic visceral leishmaniases vector were tested against: deltamethrin 0.05%, malathion 5%, dichloro-diphenyl-trichloroethane (DDT) 4%. MATERIALS AND METHODS: In leishmaniases endemic areas species specific sand fly sites were selected in Kerman province, and specimens were collected by manual aspirators at different time intervals during the spring and summer 2019. All the susceptibility tests were performed according to the WHO tube test recommended procedure. RESULTS: Twenty five blood-fed female sand flies from the region's prevalent species were used in each pooled test replicates. All wild specimens died within 60 min of exposure to DDT 4%, malathion 5%, and deltamethrin 0.05%, but the mortality rate for Ph. papatasi exposed to malathion and DDT was 91.6% and 66.6%, respectively. CONCLUSION: According to current study results, Ph. sergenti and Ph. alexandri are highly susceptible to all the evaluated insecticides in the study areas. However, Ph. papatasi was susceptible to deltamethrin (100% mortality), possibly resistant or tolerant to malathion (91.6% mortality), and confirmed to be resistant to DDT (66.6% mortality).

Significant decline of malaria incidence in a low socioeconomic area in the southeast of Iran: 10 years field assessment during malaria elimination programme.

Although malaria burden and its active foci have sharply declined after the implementation of elimination programme since 2010, it is still considered as a major public health problem in southeast Iran. This descriptive-analytical study aimed to determine 10-years of malaria epidemiological trends in Bashagard County. Data were collected from 7 selected malarious region of the county based on active and passive surveillance of clinical cases. For diagnosis of malaria, the examination of microscopic slides and rapid diagnostic test, were used. In total, 237 malaria cases were found from 2009 to 2018. Plasmodium vivax was the dominant parasite species and identified in 232 (97.9%) individuals. Males were infected more than females and the majority of malaria cases (67.4%) were recorded from rural areas. Although about 98% of malaria cases were indigenous, they have decreased form 200 cases in 2009 to zero indigenous transmission in 2018. During the study period, malaria cases had decreased significantly by about 99% and the incidence rate had declined from 5.47/1000 cases in 2009 to 0.002/1000 in 2018. The incidence of malaria, especially indigenous cases, in Bashagard County has decreased dramatically in the past 10 years. However, there is still probability of malaria re-introduction and outbreak in the county due to climatical and geographical conditions. Therefore, it is necessary to implement an active surveillance system to detect and treat malaria cases quickly, during the elimination phase in this county.

Epidemiological features of cutaneous leishmaniasis and distribution of sand flies in an endemic area in southeast of Iran.

INTRODUCTION: Cutaneous leishmaniasis (CL) is a widespread tropical infectious disease in the world. It is one of the most important health problem in Iran which is endemic in different parts of country. This study was conducted to determine epidemiological features of CL and distribution of sand flies in Hajiabad County, one of the important CL foci in southeast of Iran. METHODS: This descriptive cross-sectional study was conducted from March 2019 to March 2020.All of the suspected CL cases with skin lesions who referred to Hajiabad County health centers and all actively detected patients were clinically and parasitologically examined for CL. Demographic and clinical data of all patients were recorded. Moreover, in this study, sand flies were collected monthly from four typical plain and foothill villages during their active season (May-November) using sticky trap. Sand flies were mounted as permanent microscopic slides, using Puri's medium, and identified by taxonomic keys. Data were analyzed using SPSS.21 software and descriptive statistics. RESULTS AND DISCUSSION: A total of 70 confirmed cases of CL were recorded; the incidence rate of the disease was 101 per 100,000 people. The most infected age group was 0-10 years, with a rate of 64.3%. Males were infected more than females and the majority of cases (85.7%) were recorded from rural areas. Most of the cases had 1 lesion (51.4%) and the most lesions (55.8%) were in upper extremities. During the study period, 832 sand fly specimens comprised of ten species of Sergentomyia and seven of Phlebotomus were collected and identified. The most prevalent species was P. papatasi (47.12%), followed by P. alexandri (8.41%) and P. salehi (6.25%). Among the collected Phlebotomus species, P. papatasi and P. sergenti are known as the primary vectors of CL and P. alexandri, P. salehi, and P. caucasicus, play the main role as the secondary vectors of CL in Iran. CONCLUSION: This study has revealed that CL is endemic in Hajiabad County and there are five CL vectors that are distributed in this County and some of them are more prevalent in plain areas. These findings can be used as a basis for implementation of interventions toward vector control, which may help in suppression of vector density, and consequently, control of CL in the study area.

Monitoring and Mapping of Insecticide Resistance in Medically Important Mosquitoes (Diptera: Culicidae) in Iran (2000-2020): A Review.

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.

Risk factors associated with scabies infestation among primary schoolchildren in a low socio-economic area in southeast of Iran.

BACKGROUND: Scabies is a neglected tropical disease caused by the mite Sarcoptes scabiei that burrows under the skin. It is a major health problem in tropical areas, largely affecting children. Scabies is common and highly contagious and in schoolchildren spreads quite rapidly, due to overcrowding and close contact within the schools. This study aimed to determine the risk factors associated with scabies infestation among primary schoolchildren in Bashagard County, one of the low socio-economic areas in southeast of Iran. METHODS: To conduct this community-based, descriptive, and cross-sectional study, four primary schools were randomly selected in the Bashagard County. All students in these schools were selected and examined for scabies. Clinical examination and sociodemographic profile of students were assessed using a pre-tested structured questionnaire. Chi-square test, and binary logistic regression were used to analyse the factors associated with scabies infestation by SPSS version 21 software. RESULTS: Out of 480 studied schoolchildren, 15 cases of scabies with a prevalence of 3.1 % were observed. The frequency of infestation in males was 1.6 % and it was 4.7 % in females. Independent factors associated with a high risk of scabies infestation in unadjusted analysis were being student of grade 5-6 (cOR = 13.12, 95 % CI 2.92-58.89, p = 0.0001), low educational level of father (cOR = 4.37, 95 % CI 0.97-19.59, p = 0.036), low educational level of mother (cOR = 4.14, 95 % CI 1.92-18.57, p = 0.045), joblessness of father (cOR = 14.77, 95 % CI 4.97-43.89, p = 0.0001), employment of mother (cOR = 5.28, 95 % CI 1.38-20.16, p = 0.007), large family size (cOR = 3.34, 95 % CI 1.05-10.64, p = 0.031), use of shared articles (cOR = 33.37, 95 % CI 10.82-102.90, p = 0.0001), and absence of bathroom in the house (cOR = 11.77, 95 % CI 2.16-63.94, p = 0.0001). CONCLUSIONS: Results of this study confirmed that scabies is still one of the most important health problems in the primary schools of the Bashagard County. Low socioeconomic status and personal hygiene of the schoolchildren were the most important factors influencing the prevalence of scabies. Improvement of socioeconomic conditions and implementation of appropriate educational programs and active surveillance system to quickly detect and treat scabies cases are necessary in order to reduce the prevalence of scabies in schoolchildren in this area.

Evaluation of Susceptibility Status of Phlebotomus papatasi, the Main Vector of Zoonotic Cutaneous Leishmaniasis, to Different WHO Recommended Insecticides in an Endemic Focus, Central Iran.

Background: Among neglected zoonotic diseases, leishmaniases caused by Leishmania parasite through infected female sand fly bite, are a group of diseases found in 98 countries and territories representing a critical burden of disease worldwide. Vector management plays a crucial role in reducing the burden of vector-borne diseases by WHO's global plan. The objective of the current study was to assess the susceptibility status of wild phlebotomine sand flies from Esfahan Province, central Iran, to the recommended insecticides by WHO. Methods: Sand flies were collected by mouth aspirator in Matin Abad desert Eco-resort and were tested using WHO adult mosquito test kit against Dichlorodiphenyltrichloroethane (DDT) 4%, Deltamethrin 0.05%, Malathion 5% and Propoxur 0.1%. The number of knockdown sand flies were recorded during exposure time in ten minutes interval for DDT and Deltamethrin and they were allowed to recover for 24 hours. Knockdown Time50 (KD50) and KD90 were generated for them using Probit software. They were mounted and identified by valid keys. Results: Among the tested insecticides against female Phlebotomus papatasi, DDT, Deltamethrin, and Malathion recorded the highest mortality rate of 100%, followed by Propoxur with 92.2% mortality for a one-hour exposure. For DDT, KD50 and KD90 were calculated 21.87 and 42.93 and for Deltamethrin, they were 23.74 and 56.50 minutes respectively. Total sand flies exposed with DDT and Deltamethrin shed their leg(s). Conclusion: It is concluded that Ph. papatasi from central Iran is susceptible to DDT, Deltamethrin, Malathion, and Propoxur.

Molecular Assay on Detection of Crimean Congo Hemorrhagic Fever (CCHF) Virus in Ixodid Ticks Collected from Livestock in Slaughterhouse from South of Iran.

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 livestock 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 percent 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.

Biodiversity of Medically Important Calyptratae Flies (Diptera: Schizophora) in Hospitals in the Northern Coastline of the Persian Gulf, Iran.

Domestic filth flies play a significant role in the transmission of nosocomial infections and cause nosocomial myiasis in hospitals worldwide. This descriptive cross-sectional study was conducted in five hospitals of the Hormozgan province, of southern Iran. Adult flies were collected by bottle fly traps. Specimens were pinned and morphologically identified using the relevant keys. Species biodiversity indices including Menhinick (M), Shannon-Wiener (H'), Pielou's Evenness (E), and Simpson's diversity (D) were calculated. Totally 2,298 individuals of 18 species of flies belonging to nine genera and four families were collected. Chrysomya megacephala was the most frequent species (37.3%), followed by Chrysoma albiceps (24.8%), Fannia canicularis (5.1%), Musca domestica (4.8%), Sarcophaga aegyptica (3.7%), and 15 other species (24.4%). Our results show a high diversity and abundance of domestic filth flies in the studied hospitals. Relatively similar data derived from various hospitals in this study can show the uniformity in sanitary conditions of hospitals. On the other hand, estimation of diversity indices alarmed for potential of dominant species in fly communities in hospital environments.

Biodiversity of Mosquitoes (Diptera: Culicidae) with Emphasis on Potential Arbovirus Vectors in East Azerbaijan Province, Northwestern Iran.

BACKGROUND: The abundance, diversity, distribution and ecology of mosquitoes (Diptera: Culicidae), especially arbovirus vectors are important indices for arthropod-borne diseases control. METHODS: Larvae and adult mosquitoes were collected using the standard methods from different habitats in nine localities of three counties in the East Azerbaijan Province, Northwestern Iran during June to October 2017. In addition, species richness (R), Simpson's diversity index (D), Shannon-Wiener index (H') and evenness (E) as measures of diversity, were calculated. RESULTS: Overall, 1401 mosquito specimens including 1015 adults and 386 larvae were collected in the study area. The properties of geographical larval habitats were recorded. Four genera along with 10 species were collected and identified, including Anopheles hyrcanus, An. maculipennis s.l., An. superpictus s.l., Aedes caspius, Ae. vexans, Culex pipiens, Cx. theileri, Cx. perexiguus, Culiseta longiareolata and Cs. subochrea. Among the three counties, Ahar region presented the highest species richness (R: 1.5) and diversity values (D: 0.79, H': 1.74, E: 0.73). CONCLUSION: This study provides important information on the diversity, distribution and ecology of ten mosquito species in the region. This information leads to a better understanding of mosquito population dynamics in relation to vector control measures.

Species composition, seasonal abundance and distribution of potential anopheline vectors in a malaria endemic area of Iran: field assessment for malaria elimination.

BACKGROUND: Despite decreases in incidence, malaria remains a major public health challenge in south and southeast Iran, where vector control is considered one of the main strategies for elimination of the disease. The efficacy of this strategy depends on understanding malaria vector ecology, which varies by species. This study was conducted to determine the species composition, seasonal abundance and distribution of potential anopheline vectors in Bashagard County, one of the important malaria-endemic areas in south Iran. METHODS: In this cross-sectional study, four typical foothill and mountainous villages were selected by simple random sampling. Anopheline mosquitoes were collected by the standard dipping method for larvae and total catch for adults. Anopheline specimens were morphologically identified using taxonomic keys. Statistical analyses were performed using SPSS ver.20 software. RESULTS: In total, 1211 anopheline specimens, including 1055 (87.12%) larvae and 156 (12.88%) adults, were collected and identified. They consisted of 9 species: Anopheles moghulensis (27.89%), Anopheles dthali (18.91%), Anopheles culicifacies (16.60%), Anopheles stephensi (15.38%), Anopheles turkhudi (9.83%), Anopheles superpictus (9.66%), Anopheles apoci (1.40%), Anopheles fluviatilis (0.17%), and Anopheles sergentii (0.08%). The most prevalent species in adult catches were An. culicifacies (44.23%), An. dthali (21.15%) and An. stephensi (16.03%), and the most prevalent species caught as larvae were An. moghulensis (31.94%), An. dthali (18.85%) and An. stephensi (15.26%). Most of the anopheline species were distributed in different topographical areas and two proven malaria vectors, An. culicifacies and An. superpictus, were significantly associated with altitude and collected more frequently in the foothill regions. Most of the anopheline species were present almost throughout the year with a major peak in April and a smaller peak in October. CONCLUSION: The results of this study revealed that there are five malaria vectors in Bashagard County and some of them are more abundant in areas with special topographic features and are reproductively active throughout the year. These findings can be applied to successful planning and providing effective control measures in problematic areas during the malaria elimination phase in Iran.

Plant-Derived Essential Oils; Their Larvicidal Properties and Potential Application for Control of Mosquito-Borne Diseases.

Mosquito-borne diseases are currently considered as important threats to human health in subtropical and tropical regions. Resistance to synthetic larvicides in different species of mosquitoes, as well as environmental pollution, are the most common adverse effects of excessive use of such agents. Plant-derived essential oils (EOs) with various chemical entities have a lower chance of developing resistance. So far, no proper classification based on lethal concentration at 50% (LC50) has been made for the larvicidal activity of EOs against different species of Aedes, Anopheles and Culex mosquitoes. To better understand the problem, a summary of the most common mosquito-borne diseases have been made. Related articles were gathered, and required information such as scientific name, used part(s) of plant, target species and LC50 values were extracted. 411 LC50 values were found about the larvicidal activity of EOs against different species of mosquitoes. Depending on the obtained results in each species, LC50 values were summarized as follows: 24 EOs with LC50 < 10 µg/mL, 149 EOs with LC50 in range of 10- 50 µg/mL, 143 EOs having LC50 within 50- 100 µg/mL and 95 EOs showing LC50 > 100 µg/mL. EOs of Callitris glaucophylla and Piper betle against Ae. aegypti, Tagetes minuta against An. gambiae, and Cananga odorata against Cx. quinquefasciatus and An. dirus having LC50 of ~ 1 µg/mL were potentially comparable to synthetic larvicides. It appears that these plants could be considered as candidates for botanical larvicides.

Baseline Susceptibility of Culiseta longiareolata (Diptera: Culicidae) to Different Imagicides, in Eastern Azerbaijan, Iran.

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 LT50 value of 11.53 minutes and Fenitrothion had the least toxic effect (LT50: 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.

Essential Oil Composition and Larvicidal Evaluation of Platycladus orientalis against Two Mosquito Vectors, Anopheles stephensi and Culex pipiens.

BACKGROUND: Natural plant products as larvicides could be considered as desirable alternatives to synthetic chemical insecticides for vector management. This study was undertaken to assess the mosquito larvicide activity of the essential oil from fresh leaves of Platycladus orientalis against two medically important species of mosquito vectors. METHODS: Essential oil was extracted by hydrodistillation and analyzed with gas chromatography and mass spectrometry (GC-MS). Fresh leaves of P. orientalis tree (500g) were collected in June 2014 from Tehran, Iran and was authenticated at the Department of Medical Entomology and Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.In addition, the larvicidal potential of oil was evaluated against late-3rd or young-4th instar larvae of Anopheles stephensi and Culex pipiens under laboratory condition. The mortality counts were made after 24h and LC50 and LC90 values were calculated. RESULTS: Forty-six components in leaves of P. orientalis were identified. The major components were α-Pinene (20.17%), 3-Carene (14%) and Cedrol (9.51%). The LC50 values against An. stephensi and Cx. pipiens larvae were 11.67ppm and 18.60ppm after 24h, respectively. CONCLUSION: Platycladus orientalis oil could be considered as a natural larvicide for mosquito larval control.