The impact of climatic variables on the population dynamics of the main malaria vector, Anopheles stephensi Liston (Diptera: Culicidae), in southern Iran

Objective: To determine the significance of temperature, rainfall and humidity in the seasonal abundance of Anopheles stephensi in southern Iran. Methods: Data on the monthly abundance of Anopheles stephensi larvae and adults were gathered from earlier studies conducted between 2002 and 2019 in malaria prone areas of southeastern Iran. Climatic data for the studied counties were obtained from climatology stations. Generalized estimating equations method was used for cluster correlation of data for each study site in different years. Results: A significant relationship was found between monthly density of adult and larvae of Anopheles stephensi and precipitation, max temperature and mean temperature, both with simple and multiple generalized estimating equations analysis (P<0.05). But when analysis was done with one month lag, only relationship between monthly density of adults and larvae of Anopheles stephensi and max temperature was significant (P<0.05). Conclusions: This study provides a basis for developing multivariate time series models, which can be used to develop improved appropriate epidemic prediction systems for these areas. Long-term entomological study in the studied sites by expert teams is recommended to compare the abundance of malaria vectors in the different areas and their association with climatic variables. Abbasi Madineh 1 Deparment of Medical Entomology & Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran; Infectious and Tropical Diseases Research Center,Tabriz University of Medical Sciences, Tabriz Rahimi Foroushani Abbas 2 Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran Jafari-Koshki Tohid 3 Molecular Medicine Research Center; Department of Statistics and Epidemiology, Faculty of Health, Tabriz University of Medical Sciences, Tabriz Pakdad Kamran 4 Department of Parasitology & Mycology, Paramedical School, Shahid Beheshti University of Medical Sciences, Tehran Vatandoost Hassan 5 Deparment of Medical Entomology & Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran Hanafi-Bojd Ahmad 6 Deparment of Medical Entomology & Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran WHO. Malaria report 2019. Geneva: WHO; 2019. 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Country statistical yearbook. 1st ed. Iran: Management & Planning Organization; 2018, p.100-120. Basseri HR, Moosakazemi SH, Yosafi S. Mohebali M, Hajaran H, Jedari M. Anthropophily of malaria vectors in Kahnouj district, south of Kerman, Iran. Iran J Public Health 2005; 34(2): 27-35. Fathian M, Vatandoost H, Moosa-Kazemi H, Raeisi A, Yaghoobi-Ershadi MR, Oshaghi MA, et al. Susceptibility of Culicidae mosquitoes to some insecticides recommended by WHO in a malaria endemic area of Southeastern Iran. J Arthropod-Borne Dis 2015; 9(1): 22-34. Mojahedi A, Basseri HR, Raeisi A, Pakari A. Bioecological characteristics of malaria vectors in different geographical areas of Bandar Abbas County, 2014. J Prev Med 2016; 3(1): 18-25. Nedjati J. The study on some bioecological characteristics of malaria vectors and monitoring of their suseptibility levels to some insecticides in Sarbaz county, Sistan va Baluchestan province. MSc. Thesis. Tehran University of Medical Sciences; 2011. No. 5046. 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A physiological time analysis of the duration of the gonotrophic cycle of Anopheles pseudopunctipennis and its implications for malaria transmission in Bolivia. Malar J 2008; 7: 141. Simon-Oke IA, Olofintoye LK. The effect of climatic factors on the distribution and abundance of mosquito vectors in Ekiti State. J Biol Agri Healthcare 2015; 5(9): 142-146. Jemal Y, Al-Thukair AA. Combining GIS application and climatic factors for mosquito control in Eastern Province, Saudi Arabia. Saudi J Biol Sci 2016; 25(8):1593-1602. Msugh-Ter MM, Aondowase DA, Terese AE. Association of meteorological factors with two principal malaria vector complexes in the University of Agriculture Makurdi community, Central Nigeria. Am J Entomol 2017; 1(2): 31-38. [31 ]Kabbale FG, Akol AM, Kaddu JB, Ambrose W. Biting patterns and seasonality of Anopheles gambiae sensu lato and Anopheles funestus mosquitoes in Kamuli District, Uganda Onapa. Parasit Vectors 2013; 6: 340. 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The Ecology of Anopheles mosquitoes under climate change: Case studies from the effects of environmental changes in East Africa highlands. Ann Acad Sci 2012; 1249: 204-210. Abbasi F, Babaeian I, Malboosi SH, Asmari M, Mokhtari LG. Climate change assessment over Iran during future decades, using statistical downscaling of ECHO-G model. J Geogr Res 2012; 104: 205-230 (In Persian).

Resistance status of main malaria vector, Anopheles stephensi Liston (Diptera: Culicidae) to insecticides in a malaria Endemic Area, Southern Iran

Objective: To evaluate the susceptibility of Anopheles stephensi (An. stephensi) Liston, the main malaria vector in southern Iran, to WHO recommended insecticides. Methods: Larvae of An. stephensi were collected from three different larval habitats in both urban and rural area of Bandar Abbas city and one rural area in Rudan county southern Iran. WHO standard method was used for evaluation of adult and larval mosquito susceptibility. Bendiocarb, permethrin, lambda-cyhalothrin, deltamethrin as insecticide and temephos and chlorpyriphos as larvicide were used at the diagnostic dosages recommended by WHO. Results: Findings of this study showed all larval populations of An. stephensi were completely susceptible to temephos and candidate for resistance to chlorpyriphos. Adult mosquitoes in rural areas of Bandar Abbas city were resistant to pyrethroid and carbamate insecticides. Conclusion: Comparison of the results of this survey with previous studies indicates that the resistance to pyrethroids and carbamates in this malaria endemic region is increasing. Wide use of pesticides in agriculture is certainly effective in increasing resistance. The inter-sectoral coordination and collaboration in health and agriculture seem to be necessary to manage insecticide resistance in malaria vectors.

Repellency effect of flumethrin pour-on formulation against vectors of Crimean–Congo haemorrhagic fever

Background: Ticks are able to transmit important diseases to humans, including Rocky Mountain spotted fever, Q fever, Crimean–Congo haemorrhagic fever, summer Russian encephalitis, and relapsing fever.

Aims: To determine the repellency effect of 1% flumethrin pour-on formulation against hard ticks.

Methods: The concentration of flumethrin pour-on formulation was 1 mg/10 kg body weight and was administered on the dorsal midline from the head to the base of the tail. The livestock included cows, goats, oxen and sheep in 2 villages in Ardabil Province, Islamic Republic of Iran.

Results: We studied 200 livestock comprising 5 age groups [< 2, 3–4, 5–6, 7–8 and >8 years]. The main hard ticks identified were Hyalomma species [62.5%] and Rhipicephalus bursa [37.5%]. In the treatment village, the maximum number of ticks per animal was 11.6 in oxen, 9.5 in sheep, 8.9 in goats and 8.6 in cattle. The repellency effect of flumethrin remained for 2 months.

Conclusions: Flumethrin provided 2 months protection against hard ticks. Therefore, it could be used in the livestock industry. Control of ticks is important for prevention of disease transmission

Wash resistance and bio-efficacy of Olyset

Objective To determine the wash resistance of Olyset

Astrodaucus persicus as a new source of bioinsectisides against malaria vector, Anopheles stephensi

Objective To determine the larvicidal activities of petroleum ether, chloroform, ethyl acetate and methanol fractions of roots and fruits extracts of Astrodaucus persicus from Apiaceae family against malaria vector, Anopheles stephensi (An. stephensi). Methods Twenty five third instar larvae of An. stephensi were exposed to various concentrations (10–160 g/L) of fractions and were assayed according to World Health Organization protocol. The larval mortality was calculated after 24 h treatment. Results Among tested fractions, the highest larvicidal efficacy was observed from ethyl acetate fraction of fruits extract with 50% and 90% mortality values (LC

Wash resistance and bio-efficacy of Olyset Plus, a long-lasting insecticide-treated mosquito net with synergist against malaria vector, Anopheles stephensi

OBJECTIVE@#To determine the wash resistance of Olyset Plus using World Health Organization Pesticide Evaluation Scheme standard washing procedure and to assess the value of knock down and mortality rates of Anopheles stephensi at different regimens of long lasting insecticide treated nets washings.@*METHODS@#The study was conducted at the Bioassay Laboratory of Culicidae Insectary, School of Public Health, Tehran University of Medical Sciences, Iran. The net was made of polyester impregnated with permethrin and piperonyl butoxide at a ratio of 2:1. The washing resistance was assessed using Le Chat soap and a shaker incubator set at a speed of 155 r/min, 30 °C for 10 min. The cone bioassay test was carried out according to World Health Organization recommended guideline with tolerant field strain of female Anopheles stephensi to pyrethroids.@*RESULTS@#The knockdown and mortality rates of female mosquitoes exposed to Olyset Plus from un-washed nets to 2 washings were 79.7% and 88.8% respectively. Mortality was dropped to zero while active ingredient estimated 0.532 μg/100 cm to 0.481 μg/100 cm after 15 washings. A positive correlation was seen between residues of permethrin on nets, knockdown rate and mortality rate of female Anopheles stephensi exposed to different regimes of washed Olyset Plus (r = 0.954, P = 0.001).@*CONCLUSIONS@#It is recommended that a preliminary survey conducted on resistance level of Anopheles vectors before the distribution of Olyset Plus in malaria endemic communities.

Astrodaucus persicus as a new source of bioinsectisides against malaria vector, Anopheles stephensi

OBJECTIVE@#To determine the larvicidal activities of petroleum ether, chloroform, ethyl acetate and methanol fractions of roots and fruits extracts of Astrodaucus persicus from Apiaceae family against malaria vector, Anopheles stephensi (An. stephensi).@*METHODS@#Twenty five third instar larvae of An. stephensi were exposed to various concentrations (10-160 g/L) of fractions and were assayed according to World Health Organization protocol. The larval mortality was calculated after 24 h treatment.@*RESULTS@#Among tested fractions, the highest larvicidal efficacy was observed from ethyl acetate fraction of fruits extract with 50% and 90% mortality values (LC and LC) of 34.49 g/L and 108.61 g/L, respectively. Chloroform fraction of fruits extract was the second larvicidal sample with LC of 45.11 g/L and LC of 139.36 g/L. Petroleum ether fractions of fruits and roots and methanol fraction of fruits showed moderate toxicity against An. stephensi.@*CONCLUSIONS@#Astrodaucus persicus is a potential source of valuable and natural larvicidal compounds against malaria vector, An. stephensi and can be used in mosquitoes control programs as an alternative to synthetic insecticides.

Susceptibility of Anopheles maculipennis to different classes of insecticides in West Azarbaijan Province, Northwestern Iran

OBJECTIVE: To determine the susceptibility status of Anopheles maculipennis (An. maculipennis) against the major insecticides used in the health sectors in West Azarbaijan Province, Northwestern Iran. METHODS: Unfed 3-5 days old adult females of An. maculipennis were collected across the West Azarbaijan Province and were subjected to evaluation of their susceptibility following World Health Organization recommended protocol against six insecticides (permethrin, deltamethrin, propoxur, bendiocarb, malathion and dieldrin) belonging to four different classes. RESULTS: In this study, 916 specimens of An. maculipennis were examined against the insecticides which indicated that An. maculipennis was tolerant to permethrin, deltamethrin and dielderin, but displayed resistance against propoxur, bendiocarb and malathion. CONCLUSIONS: The pattern of resistance in An. maculipennis could be attributed to the agricultural landscapes, agricultural pesticides used and the exposure of the mosquitoes to insecticides. Logical cooperation is needed between the agriculture and health sectors to ensure the judicious use of pesticides in each sector and the management of probable resistance.

Characterization of larval habitats for anopheline mosquitoes in a malarious area under elimination program in the southeast of Iran

<p><b>OBJECTIVE</b>To determine the effects of environmental characteristics of larval habitats on distribution and abundance of anopheline mosquitoes in Bashagard county, a malarious area in southeast of Iran.</p><p><b>METHODS</b>Larvae were collected monthly using the standard dipping method and identified using a morphological-based key. Environmental characteristics of the larval habitats were recorded. Water samples were taken from habitats during larval collection for physico-chemical characterization. Statistical analyses were performed.</p><p><b>RESULTS</b>In total 5 150 anopheline larvae from 36 larval habitats were collected and identified. They comprised of six species: Anopheles culicifacies (29.36%), Anopheles moghulensis (25.20%), Anopheles dthali (18.02%), Anopheles superpictus (17.24%), Anopheles turkhudi (5.17%) and Anopheles stephensi (5.01%). The most common larval habitats were natural and clear water bodies such as riverbeds with sandy substrates and still water. Furthermore, the anopheline larvae were abundant in permanent and full sunlight habitats without vegetation and algae. Larval density was positively correlated with water temperature. Chemical characteristics including conductivity, total alkalinity, sulphate and chloride had significant effects on distribution and abundance of anopheline species.</p><p><b>CONCLUSIONS</b>The result of this study indicates a correlation between some environmental characteristics and anopheline larvae abundance which can be considered for effective planning and implementing malaria elimination program in Iran.</p>

The insecticidal effect of diatomaceous earth against adults and nymphs of Blattella germanica

<p><b>OBJECTIVE</b>To evaluate the insecticidal effect of diatomaceous earth (DE) against adults and nymphs of Blattella germanica.</p><p><b>METHODS</b>This cross sectional study has been done on the laboratory strain of German cockroaches. Two stages, nymph and adult, were exposed to six dose rates of the DE, 2.5, 5, 10, 15, 20 and 25 g/m(2), at 24, 48 and 72 h exposure period. Mortality (number of dead cockroaches) was assessed after 24 h. Other exposed specimens were transferred to the beakers contained food and water for counting the retard mortality rate after 1 week.</p><p><b>RESULTS</b>Increasing in dose rates of DE increased mortality rate, so that the lowest and highest mortality rates were observed in 2.5 and 25 g/m(2), respectively. The results of the statistical analysis showed no significant difference in the lethality of 50% of DE plus water on the German cockroach nymphs.</p><p><b>CONCLUSIONS</b>Due to the resistance of German cockroach against organochloride, organophosphorus, carbamate and pyrethriodes insecticides, it is suggested to use DE for insect's control.</p>

Malaria elimination in Iran, importance and challenges

The aim of study is to assess the importance and challenges of Malaria elimination [ME] in Iran's health system. Opinion of experts from Ministry of Health and Medical Education and the chancellors of medical universities affected by malaria were gathered using Focus Group Discussions and in-depth interviews. We asked them about the importance and main challenges of ME in Iran. Main factors on importance of ME were: it's a struggle to reach to equity in the poorest regions of county, prevention of emerging disease in susceptible regions, lowering the cost of control and its effects on the region's socioeconomic condition. Main challenges were Iran's long border with malaria-endemic countries Pakistan and Afghanistan and illegal immigrants, underdevelopment in rural areas, system's insensitivity and diagnosis problem due to reduction of cases. Quantitative and holistic researches are needed for assessing the consequences of ME

Larvicidal activities of some Iranian native plants against the main malaria vector, anopheles stephensi

Malaria is considered a major health problem in Iran. There are different methods for vector control. In this study we tested the larvicidal effects of some Iranian plants. The methanolic extracts of 11 plants were prepared with percolation method. The larvicidal activities of them against malaria vector, Anopheles stephensi were studied using World Health Organization standard method. All LC[50] values of methanolic extracts of plants that we screened were lower than 300 ppm. The methanolic extract of aerial parts of Lawsonia inermis and Stachys byzantine showed high larvicidal activity with LC[50] values 69.40 ppm and 103.28 ppm respectively. The results obtained from this study suggest that the methanolic extracts of these plants have larvicidal effects against Anopheles stephensi larvae and could be useful in the search for new natural larvicidal compounds

Environmental characteristics of anopheline mosquito larval habitats in a malaria endemic area in Iran

OBJECTIVE@#To determine the effects of environmental parameters of larval habitats on distribution and abundance of anopheline mosquitoes in Rudan county of Iran.@*METHODS@#This cross-sectional study was conducted during the mosquito breeding season from February 2010 to October 2011. The anopheline larvae were collected using the standard dipping method. The specimens were identified using a morphological-based key. Simultaneously with larval collection, environmental parameters of the larval habitats including water current and turbidity, sunlight situation, and substrate type of habitats were recorded. Water samples were taken from breeding sites during larval collection. Before collection of samples, the water temperature was measured. The water samples were analysed for turbidity, conductivity, total alkalinity, total dissolved solid, pH and ions including chloride, sulphate, calcium, and magnesium. Statistical correlation analysis and ANOVA test were used to analyze the association between environmental parameters and larval mosquito abundance.@*RESULTS@#In total 2 973 larvae of the genus Anopheles were collected from 25 larval habitats and identified using morphological characters. They comprised of six species: An. dthali (53.21%), An. stephensi (24.22%), An. culicifacies (14.06%), An. superpictus (4.07%), An. turkhudi (3.30%), and An. apoci (1.14%). The most abundant species was An. dthali which were collected from all of the study areas. Larvae of two malaria vectors, An. dthali and An. stephensi, co-existed and collected in a wide range of habitats with different physico-chemical parameters. The most common larval habitats were man-made sites such as sand mining pools with clean and still water. The anopheline mosquitoes also preferred permanent habitats in sunlight with sandy substrates. The results indicated that there was a significant relationship between mean physico-chemical parameters such as water temperature, conductivity, total alkalinity, sulphate, chloride, and mosquito distribution and abundance.@*CONCLUSIONS@#The results of this study showed a correlation between certain environmental parameters and mosquito larvae abundance, and these parameters should be considered in planning and implementing larval control programs.

Effects of educational intervention on long-lasting insecticidal nets use in a Malarious area, Southeast Iran

Long-lasting insecticidal nets [LLINs] have been advocated as an effective tool against malaria transmission. However, success of this community based intervention largely depends on the knowledge and practice regarding malaria and its prevention. According to the national strategy plan on evaluation of LLINs [Olyset nets], this study was conducted to determine the perceptions and practices about malaria and to improve use of LLINs in Bashagard district, one of the important foci of malaria in Southeast Iran. The study area comprised 14 villages that were randomized in two clusters and designated as LLINs and untreated nets. Each of households in both clusters received two bed nets by the free distribution and delivery. After one month quantitative data collection method was used to collect information regarding the objectives of the study. On the basis of this information, an educational program was carried out in both areas to increase motivation for use of bed nets. Community knowledge and practice regarding malaria and LLIN use assessed pre- and post-educational program. The data were analyzed using SPSS ver.16 software. At baseline, 77.5% of respondents in intervention and 69.4% in control area mentioned mosquito bite as the cause of malaria, this awareness increased significantly in intervention [90.3%] and control areas [87.9%], following the educational program. A significant increase also was seen in the proportion of households who used LLINs the previous night [92.5%] compared with untreated nets [87.1%]. Educational status was an important predictor of LLINs use. Regular use of LLIN was considerably higher than the targeted coverage [80%] which recommended by World Heaths Organization. About 81.1% and 85.3% of respondents from LLIN and control areas reported that mosquito nuisance and subsequent malaria transmission were the main determinants of bed net use. These findings highlight a need for educational intervention in implementation of long-lasting insecticidal nets; this should be considered in planning and decision-making in the national malaria control program during the next campaigns of LLINs in Iran

Ecology of anopheles stephensi in a malarious area, southeast of Iran

District of Jiroft is situated in south-east of Iran which is one of the malarious regions. Anopheles stephensi is considered as one of the main malaria vector in this region. Ecology of this species was studied in the area to understand its vector behavior for implementation of effective vector control measures. Different methods like total catch, pit shelter, night bite collection on human and animal, larval dipping methods were used for species identification, seasonal activity, anthropophilic index and egg morphological characteristics. Anthropophilicity index was assessed by ELISA test. Activity of Anopheles species started at the beginning of April, and its peak occurs in late spring. The larvae were found in the river bed with pools, stagnant streams, slow foothill streams, temporary pools, and slowly moving water with and without vegetation, drainage containers of air conditioner and palm irrigation canals. From different methods of adult collection, it was found that spray sheet collection is the appropriate method. ELISA testing of 144 blood meals of females revealed the anthropophilicity of 11.8% indicating host preference on animal, mainly cow. Ridge length and their number on the egg floats confirmed Anopheles stephensi mysorensis form. This study showed that Anopheles stephensi is the main vector of malaria in the region, although some other species may play a role. Our findings could provide a valuable clue for epidemiology and control of malaria in the southeast of Iran

Confirmation of two sibling species among anopheles fluviatilis mosquitoes in south and southeastern Iran by analysis of cytochrome oxidase I gene

Anopheles fluviatilis, one of the major malaria vectors in Iran, is assumed to be a complex of sibling species. The aim of this study was to evaluate Cytochrome oxidase I [COI] gene alongside 28S-D3 as a diagnostic tool for identification of An. Fluviatilis sibling species in Iran. DNA sample belonging to 24 An. Fluviatilis mosquitoes from different geographical areas in south and southeastern Iran were used for amplification of COI gene followed by sequencing. The 474-475 bp COI sequences obtained in this study were aligned with 59 similar sequences of An. Fluviatilis and a sequence of Anopheles minimus, as out group, from GenBank database. The distances between group and individual sequences were calculated and phylogenetic tree for obtained sequences was generated by using Kimura two parameter [K2P] model of neighbor-joining method. Phylogenetic analysis using COI gene grouped members of Fars Province [central Iran] in two distinct clades separate from other Iranian members representing Hormozgan, Kerman, and Sistan va Baluchestan Provinces. The mean distance between Iranian and Indian individuals was 1.66%, whereas the value between Fars Province individuals and the group comprising individuals from other areas of Iran was 2.06%. Presence of 2.06% mean distance between individuals from Fars Province and those from other areas of Iran is indicative of at least two sibling species in An. Fluviatilis mosquitoes of Iran. This finding confirms earlier results based on RAPD-PCR and 28S-D3 analysis

Irritability of malaria vector, Anopheles sacharovi to different insecticides in a malaria-prone area

OBJECTIVE@#To determine the susceptibility and irritability level of malaria vector Anopheles sacharovi (An. sachrovi) to different insecticides in a malaria-prone area.@*METHODS@#Susceptibility and irritability levels of field collected strain of An. sacharovi to WHO standard papers of DDT 4%, dieldrin 0.4%, malathion 5%, fenitrothion 1%, permethrin 0.75%, and deltamethrin 0.05% were determined in East Azerbaijan of Iran during reemerging of malaria as described by WHO.@*RESULTS@#Results showed that at the diagnostic dose of insecticides this species exhibited resistance to DDT, tolerant to dieldrin and but somehow susceptible to fenitrothion, malathion, permethrin and deltamethrin. The results of irritability of this species to DDT, lambdacyhalothrin, permethrin cyfluthrin and deltamethrin revealed that DDT had had the most and deltamethrin the least irritancy effect. The average number of take offs/fly/minutes for DDT was 0.8±0.2. The order of irritability for permethrin, lambdacyhalothrin, cyfluthrin and deltamethrin were 0.7±0.2, 0.5±0.2, 0.5±0.3, and 0.2±0.1, respectively.@*CONCLUSIONS@#Results of this study reveals the responsiveness of the main malaria vector to different insecticides. This phenomenon is depending on several factors such as type and background of insecticide used previously, insecticide properties, and physiology of the species. Careful monitoring of insecticide resistance and irritability level of species could provide a clue for appropriate selection of insecticide for malaria control.

Indication of pyrethroid resistance in the main malaria vector, Anopheles stephensi from Iran

OBJECTIVE@#To investigate insecticide resistance in target species for better insecticide resistance management in malaria control programs.@*METHODS@#The status of insecticide resistance to different imagicides in Anopheles stephensi (An. stephensi) including DDT 4%, lambdacyhalothrin 0.50%, deltamethrin 0.05%, permethrin 0.75%, cyfluthrin 0.15% and etofenprox 0.50% was performed according to WHO standard method.@*RESULTS@#The mortality rate to lambdacyhalothrin, permethrin, cyfluthrin, deltamethrin, etofenprox and DDT was (88.0 ± 3.2), (92.0 ± 2.7), (52.0 ± 5.0), (96.0 ± 2.2), (90.0 ± 3.0) and (41.0 ± 5.7) percent, respectively at diagnostic dose for one hour exposure time followed by 24 h recovery period.@*CONCLUSIONS@#These results showed first indication of pyrethroid resistance in An. stephensi in a malarious area, from southern Iran. There is widespread, multiple resistances in the country in An. stephensi to organochlorine and some report of tolerance to organophosphate insecticides and recently to pyrethroids. However, results of this paper will provide a clue for monitoring and mapping of insecticide resistance in the main malaria vector for implementation of any vector control.

Spatio-temporal distribution of malaria vectors (Diptera: Culicidae) across different climatic zones of Iran

Malaria is a main vector-borne public health problem in Iran. The last studies on Iranian mosquitoes show 31 Anopheles species including different sibling species and genotypes, eight of them are reported to play role in malaria transmission. The objective of this study is to provide a reference for malaria vectors of Iran and to map their spatial and temporal distribution in different climatic zones. Shape files of administrative boundaries and climates of Iran were provided by National Cartographic Center. Data on distribution and seasonal activity of malaria vectors were obtained from different sources and a databank in district level was created in Excel 2003, inserted to the shape files and analyzed by ArcGIS 9.2 to provide the maps. Anopheles culicifacies Giles s.l., Anopheles dthali Patton, Anopheles fluviatilis James s.l., Anopheles maculipennis Meigen s.l., Anopheles sacharovi Favre, Anopheles stephensi Liston, and Anopheles superpictus Grassi have been introduced as primary and secondary malaria vectors and Anopheles pulcherrimus Theobald as a suspected vector in Iran. Temporal distribution of anopheline mosquitoes is restricted to April-December in northern Iran, however mosquitoes can be found during the year in southern region. Spatial distribution of malaria vectors is different based on species, thus six of them (except for Anopheles maculipennis s.l. and Anopheles sacharovi) are reported from endemic malarious area in southern and southeastern areas of Iran. The climate of this part is usually warm and humid, which makes it favorable for mosquito rearing and malaria transmission. Correlation between climate conditions and vector distribution can help to predict the potential range of activity for each species and preparedness for malaria epidemics.

A Survey of Dung Beetles Infected with Larval Nematodes with Particular Note on Copris lunaris Beetles as a Vector for Gongylonema sp. in Iran

Dung beetles (family Scarabaeidae) are one of the largest families of beetles worldwide. Due to biological behavior of these arthropods, they are considered to play an important role in the life cycle of some helminths. In the present study, dung beetles collected from cattle pastures in rural areas of Ardabil province, north-west of Iran were examined for infection with larval stages of helminths. According to the results, nematodes of 2 genera were identified including Rhabditis and Gongylonema. The more common species was Rhabditis sp. which was found in 9 species of beetles. Out of 15 different species of dung beetles, Copris lunaris was the only scarabaeid to be found naturally infected with the larval stages of Gongylonema sp. Our new findings introduce C. lunaris as a potential biological vector for transmission of Gongylonema sp. to vertebrates in the surveyed region.