[Entomological research and its specific course in Iran from 1935 to 2008]

Malaria remains an important vector-borne disease globally and is a threat for human life. Forty percent of the world's populations who are living in low-income countries are at risk of malaria. The disease exists in Iran and caused economic and social damages. As result of malaria control program that has been done during the past years, the disease is eliminated from the most parts of the country, so that it is only reporting from a small part in these years. During this study, all available papers, books and thesises were reviewed and articles from Iranmedex, DIS and PubMed databanks were also used. Furthermore the related reports from different sources were noted. The extensive studies have important information about malaria vectors. In this study the data about malaria vectors and related training courses are listed. During this study the related papers, Books and thesises which have been reviewed. Although efforts, surveillance system, diagnostic and treatment facilities, as well as knowledge and attitude of peoples regarding to health behavior are improved nowadays, there are significant improvements about decreasing the malaria cases. Risk of the disease exists because of population exchange and asymptomatic cases. The malaria can be studied with both public health and economical aspects. This paper represents entomological studies of malaria during 1935 by the end of 2008. our study revealed that, based on recent malaria national program, the authorities should make an emphasis on vector control monitoring, resistance management, malaria evaluation and because of weak supervision on all malaria operation at stage of elimination of malaria, accurate and careful suppersional require to reach the objective and goal of elimination

Mosquito [diptera: culicidae] fauna of Qom province, Iran

There is very little information about the mosquito fauna of Qom Province, central Iran. By now only three species; Anopheles claviger, An. multicolor, and An. Superpictus have been reported in the province. To study mosquito fauna and providing a primary checklist, an investigation was carried out on a collection of mosquitoes in this province. To study the mosquito [Diptera: Culicidae] fauna, larval collections were carried out from different habitats on 19 occasions using the standard dipping technique during spring and summer 2008 and 2009. In total, 371 mosquito larvae were collected and morphologically identified including 14 species representing four genera: Anopheles claviger, An. marteri, An. turkhudi, An. superpictus, Culex arbieeni, Cx. hortensis, Cx. mimeticus, Cx. modestus, Cx. pipiens, Cx. territans, Cx. theileri, Culiseta longiareolata, Cs. subochrea, and Ochlerotatus caspius s.l. All species except for An. Claviger and An. Superpictus were collected for the first time in the province. All larvae were found in natural habitats. The association occasions and percentages of the mosquito larvae in Qom Province were discussed. There are some potential or proven vectors of different human and domesticated animal pathogens in Qom Province. The ecology of these species and the unstudied areas of Qom Province need to be investigated extensively

[Comparison of PBO and DEF effects on creating bendiocarb and carbaryl insecticide resistance in German cockroach]

German cockroach [Blattella germanica, Blattodea:Blattellidae] is considered one of the common pests in hospitals, hotels, households and dormitories which can transfer different pathogenic fungi, viruses and bacteria. The aim of this study was to determine the resistance mechanisms to bendiocarb and carbaryl in German cockroache, in vivo. In this study, German cockroach strains were collected from several hospitals and dormitories in Tehran and transferred to insectarium. The strains were reared under the same laboratory conditions. At first the discriminative doses of bendiocarb and carbaryl were determined by surface contact method. Then the susceptibility level and types of resistance mechanisms to bendiocarb and carbaryl, in the strains were studied by using PBO and DEF as synergists. Simultaneous use of DEF as synergist, with bendiocarb and carbaryl led to the breakdown of resistance in all strains. But use of PBO instead of DEF did not overcome the resistance in the strains collected from Mofid, Alvand and Vali Asr hospitals and Shariati dormitory. In general, the effect of DEF in breaking the resistance was more than that of PBO. Complete breakdown of resistance after simultaneous use of DEF with bendiocarb and carbaryl insecticides, indicated the essential role of esterase enzymes in producing resistance to bendiocarb and carbaryl in the strains. But PBO did not break the resistance completely in most wild strains, which may be due to other possible mechanisms of resistance such as reduction of cuticle penetration or insensitivity to acetyl cholinesterase enzyme

Mass rearing of anopheles stephensi on human blood by artificial feeding under laboratory conditions

In order to control the diseases that are transmitted to human and animal by arthropod vectors, it is necessary to investigate vectors and to recognize control methods as well. These studies are applicable by rearing the colonies of arthropod blood-feeders like malaria and leishmaniasis in laboratory. The purpose of this study was to produce mass production of Anopheles stephensi [Lis.] by artificial feeding with human blood in insectary. We prepared an apparatus composed of a digital thermostat with sensor, element, contractor and magnet in order to blood-feed An. Stephensi. The Para film "M" and a human whole blood unit were used as a membrane and nutrient source for artificial feeding, respectively. The blood was placed in a soft lid and its surface was covered with Para film "M". The soft drink lids with blood were placed on the cage surface and indirectly warmed by element. An. Stephensi fed from blood. Three consecutive generations were reared without blood-feeding on host alike from the egg of mother colony. Female mosquito feeding rate was 47.7% to 64%. The average females feeding and ovipositing times were 10 and 9 times, respectively. No mortality was seen among the larvae. All of the pupae emerged to the adult. The second and third generation of population ratios to first population generation was 6 and 25 folds, respectively. Our findings showed that artificial feeding by human blood, especially in the investigational projects was completely efficient and suitable for increasing mosquitoes' population in specific time

Fauna and checklist of mosquitoes [Diptera: Culicidae] of east Azerbaijan province, northwestern Iran

In order to study the mosquito [Diptera: Culicidae] fauna of East Azerbaijan Province, some samplings were carried out by dipping method for the larvae and hand catch, night biting catch, total catch, and shelter pit collection as well as using window trap for the adults during June, July, and August 2004 plus July and August 2005. In total, 1305 adult mosquitoes and 603 larvae were collected. Seven genera and 15 species were identified in the province including; Anopheles claviger, An. hyrcanus, An. maculipennis s.l., An. pseudopictus, An. sacharovi, An. superpictus, Aedes vexans, Coquillettidia richiardii, Cx. pipiens, Cx. theileri, Cx. tritaeniorhynchus, Culiseta longiareolata, Cs. subochrea, Ochlerotatus caspius s.l., and Uranotaenia unguiculata. An. maculipennis complex, Cx. pipiens, and Cx. theileri were the most prevalent and widely distributed species. An. pseudopictus, Ae. vexans, and Cq. richiardii are reported for the first time in East Azerbaijan Province and a checklist for the mosquitoes of the province is also presented. Among the mosquitoes of the province, there are many potential vectors of human and domesticated animal pathogens that their ecology needs to be studied extensively

Comparison of Permethrin and Fipronil toxicity against German cockroach [Dictyoptera: Blattellidae] strains

Control of insect pests of agriculture, economic, and medical importance usually focuses on the use of insecticides. The susceptibility levels of eleven strains of German cockroaches, Blattella germanica [L.], were compared with a standard susceptible strain against permethrin and fipronil. The strains were collected from nine infested students' dormitories and two infested hospitals in Tehran, capital of Iran. The susceptible strain showed LD50 of 0.43 micro g and 0.96 ng for permethrin and fipronil respectively. Comparison of the resistance ratio of collected strain with susceptible strain showed resistance ratios of 8.6 to 17.7-folds for permethrin and 1.5 to 2.6-folds for fipronil, respectively. The result of this investigation indicated that the all strains were resistant to permethrin. Resistance spectrum of fipronil to permethrin showed different pattern of susceptibility to fipronil, indicating that there was no relationship between resistance to permethrin and fipronil

Effect of fipronil on permethrin sensitive and permethrin resistant strains of blattella germanica

Strategies to manage resistance to insecticides have usually been designed when resistance has already been developed. However, if the likelihood of resistance development to novel insecticides can be predicted before their use, it should be possible to establish an effective resistance management program. The current study was designed to investigate the effect of fipronil against permethrin sensitive and permethrin resistant strains of Blattella germanica [L.] for effective control of this pest in Iran in the future. In order to conduct this study eleven feral German cockroach strains were collected from infested student dormitories of Tehran University of Medical Sciences, Sanatee Sharif, Tarbiat Modares and Tehran Universities and also residential Saman Apartments, and two infested hospitals in Tehran. Their sensitivity to permethrin and fipronil were compared with that of a standard susceptible strain. Tests were conducted on newly emerged adult males [ultimately 21 years old] by topical application. LD[50]'s of permethrin and fipronil for the susceptible strain were 0.43/micro g and 0.96 ng respectively. The resistance of feral strains to permethrin was 8.6 to 17.7 times as much as that of the susceptible strain. According to this investigation all strains are resistant to permethrin, whereas resistance rates of the strains from Bustan-10, Zanjan Fatemiyeh dormitories and residential Saman Apartments were 2 to 2.6 times more than that of the susceptible strain. Other strains were completely susceptible to fipronil. According to the results of this study and considering ever-increasing infestation of human habitations by German cockroach and the resistance to insecticides; fipronil especially its toxic bait formulations can be regarded as the appropriate candidate to control this pest in Iran

protection of permethrin-treated military uniforms against natural population of Culex bitaeniohynchus, Culex ritaeniorhynchus and Culex perexiguus [Diptera: Culicidae]

Personnel of military forces have close contact with the environment and can be bitten by insects and exposed to the related diseases, more than other people. The importance of Culex mosquitoes for mankind is in fact, its biting and nuisance, especially at sleeping time. In recent years, great progresses have occurred in protecting people, especially military personnel, against arthropod bites and vector-borne disease, using treated clothes with permethrin. In this study, the protection of permethrin-treated military uniforms against 3 species of Culex in a rural field of Iran has been examined. In this study, six types of current military uniforms of Iran were treated by permethrin [0.125mg permethrin [Al]/cm[2] and examined against the biting of natural population mosquitoes of rural areas of Kazeroon, Fars Province, south of Iran, namely Culex. Eight volunteers were selected for this study. Six of them put on the treated uniforms and the other two wore the untreated uniforms. All the subjects participated in the night biting test for eight active nights of July 2004. There was no significant difference in the protection of different treated uniforms against mosquitoes biting. The relative protection level of treated uniforms, in comparison with untreated ones, was about 88/2%. The protection percentage of treated uniforms for different species of mosquitoes, in comparison with untreated ones, was calculated through determining the species of captured mosquitoes, separately from case and control subjects. The results showed that the relative protection percent of treated uniforms against species of Culex bitaeniohynchus, Cx. tritaeniorhynchus and Cx.perexiguus were 72.7, 87 and 89.8, respectively. The results of chemical analysis with High performance Thin Layer Chromatography [HPTLC] method, before and after field test, showed that in two weeks of study, there hasn't been any significant decrease in the amount of uniforms' permethrin. According to this study, using of permethrin-treated clothing is a useful technique, which makes a considerable protection against insects biting. Therefore using this technique is recommended for protecting military personnel or civilians, as an effective method against hematophagous insects

[ comparison of different membranes and blood for artificial feeding system of a stephensi]

The efficiency of artificial feeding system of mosquitoes kept in insectrium depends on its technology of designing, king of membrane and food quality. This study was conducted to find the best membrane and food regimen among three prevalent membranes [Parafilm "M", sheep intestine and chicken skin]. Numbers of attracted mosquitoes were recorded in one hour of exposure as a measure of comparisons. The experiment was conducted in constant circumstances of insectrium [temperature: 28+2C and relative humidity: 70%+ 10%]. Each experiment contained three replicates a lot of 20 non-blood_fed[sugar fed] 4-5 days old Anopheles stephensi. In statistical of the results of comparing membranes there was not any significant difference between the mean [P=0.07]. However, statistical analysis of the results of comparing bloods revealed that the difference between the means is meaningful. Considering the obtained results and the experiments "M" as an applicable membrane and sheep defibrinate blood as a suitable food regimen is recommended for artificial feeding of an, stephensi

efficacy of permethrin-treated military uniforms as a personal protection against culex pipiens [diptera: culicidae] and its environmental consequences

Naturally, there are different species of Culex mosquitoes in Iran. Culex pipiens complex is widespread in many parts of the country, specially in urban areas. In spite of this fact that Cx. pipiens species is the vector of some orboviruses and filariasis in many countries of the World, it does not have an important role in transmission of diseases in Iran. This species can easily reproduce in urban areas, due to the infection of surface waters and presence of sewage canals. The importance of Cx.pipiens for mankind is in fact, its biting and nuisance, specially at sleeping time. In this study, six types of current military uniforms of Iran's army were treated by permethrin [0.125 mg. permethrin [AI]/cm2] and examined against the biting of natural population of Cx.pipiens in urban areas in Tehran. Eight volunteer were selected for this study. Six of them put on the treated uniforms and the other two of them wore the untreated uniforms. All the subjects participated in the night biting test for eight active nights July 2004. There was no significant difference in the protection of different treated uniforms against mosquitoes biting. The average number of biting among who wore untreated uniforms [control] was 2.14 mosquito biting/min/person [128.2/hr], While it was 0.23 [13.8/hr] for who wore treated uniforms. The percent protection of treated uniforms, in comparison with untreated ones, was about 89%. The protection percent of treated uniforms for different species of mosquitoes, in comparison with untreated ones, was calculated through determining the species of captured mosquitoes, separately from case and control subjects. The results of species identification among captured mosquitoes of a field study showed that about 95% of them are of Cx.pipiens species, and protection of treated uniforms against them, was estimated 87%. Moreover, as an accompaning environmental consequence a significant reduction in mosquito's density was seen

subfamily Culicinae [Diptera:culicidae] in kerman province southern Iran

There are some arboviral and parasitic diseases which are transmitted by culicine mosquitoes in Iran. Three genera and eleven species of the subfamily Culicinae [Diptera: Culicidae] were collected by dipping method and identified in Kahnooj district, Kerman province, south-eastern Iran, during October and November, 2003 including; Culex [Culex] bitaeniorhynchus, Cx. [Maillotia] deserticola, Cx. [Cux.] laticinctus, Cx. [Cux.] perexiguus, Cx. [Cux.] pipiens, Cx.[Cux.] quin- quefasciatus, Cx.[Cux.] sinaiticus, Cx.[Cux.] theileri, Cx.[Cux.] tritaeniorhynchus, Culiseta [Allotheobaldia] longiareolata, and Uranotaenia [Pseudoficalbia] unguiculata. In this study, Ur.unguiculata was identified in Kerman province for the first time. Fauna and ecology of Culicinae need more investigations in this province

[ protection of permethrin-treated military uniforms against natural population of Culex bitaeniohynchus, Culex ritaeniorhynchus and Culex perexiguus [Diptera: Culicidae]]

Background: Personnel of military forces have close contact with the environment and can be bitten by insects and exposed to the related diseases, more than other people. The importance of Culex mosquitoes for mankind is in fact, its biting and nuisance, especially at sleeping time. In recent years, great progresses have been occurred in protecting people, especially military personnel, against arthropod bites and vector-borne disease, using treating clothes with permethrin. In this study, the protection of permethrin-treated military uniformsagainst 3 species of Culex in a rural field of Iran has been examined

Materials and Methods: In this study, six types of current military uniforms of Iran were treated by permethrin [0.125mg permethrin [Al]/cm[2]] and examined against the biting of natural population mosquitoes of rural areas of Kazeroon, Fars Province, south of Iran, namely Culex. Eight volunteers were selected for this study. Six of them put on the treated uniforms and the other two ones wore the untreated uniforms. All the subjects participated in the night biting test for eight active nights of July 2004

Results: There was no significant difference in the protection of different treated uniforms against mosquitoes biting. The relative protection level of treated uniforms, in comparison with untreated ones, was about 88/2%. The protection percentage of treated uniforms for different species of mosquitoes, in comparison with untreated ones, was calculated through determining the species of captured mosquitoes, separately from case and control subjects. The results showed that the relative protection percent of treated uniforms against species of Culex bitaeniohynchus, Cx. tritaeniorhynchus and Cx. perexiguus were 72.7, 87 and 89.8, respectively .The results of chemical analysis with High performance Thin Layer Chromatography [HPTLC] method, before and after field test, showed that in two weeks of study, there hasn't been any significant decrease in the amount of uniforms' permethrin

Conclusions : According to this study, using of permethrin-treated clothing is a useful technique, which makes a considerable protection against insects biting. Therefor using this technique is recommended for protecting military personnel or civilian, as an effective method against hematophagous insects

device for detection of the residual activity of beta-cyfluthrin [responsar 12.5 % SC] as a new pyrethroid on different surfaces against blattella germanica [orthoptera: blattellida]

This study was designed to evaluate the efficacy of beta-cyfluthrin [Responsar 12.5% SC], against a standard susceptible strain of German cockroach, Blattella germanica, using three different dosages, at three different exposure times, on two types of surface, parlous [mosaic] and non parous [glassed ceramic of tiles]. Comparison of the resifts indicated that beta-cyfluthrin at 12.5 a.i.mg/m2, has negligent residual activity on both mosaic and glazed ceramic tiles from one to two weeks. However at 25 a.i.mg/m2 [highest dosage], had the longest residual activity on mosaic, it was active for six, seven and nine weeks, while on glazed ceramic tiles the residual activity increased slightly to seven and nine and nine weeks, when the nymphac were exposed for 10, 15 and 20 min, respectively. These results of the bio-assay test indicate that 12.5 a.i.mg/m2 is too low for any residual spraying. Application of beta-cyfluthrin at a target dosage rate of 25 and 37.5 a.i.mg/m2 showed longer residual deposit effect than the earlier dosage. Hence these dosages could be recommended for light and heavy infested area, respectively. This study is also recommends a simple device for measuring the residual activity of insecticides against German cockroach either in laboratory or in the field conditions

Suceptibility of different field strains of blattella germanica four pyrethroids [orthoptera: blattellidae]

The susceptibility of 5 wild strains of German cockroach collected from five infected flats in Tehran were assessed by tests of surface contact method to cyfluthrin, permethrin, sumithrin and lambdacyhalothrin. Comparison of the result of knockdown tests on the wild strains with a standard susceptible strain indicated that all the strains are resistant to sumithrin, i.e., resistance ratio, the RR, ranged from 309 to 7.75 folds; but susceptible to beta - cyfluthrin [RR < 1.5]. Permethrin tests on the field collected strains revealed that 3 out of 5 strains are resistant [RR = 2.9 to 3 folds] but two are tolerant to permethrin [RR ranged between 2.24 to 2.5 folds]. Further tests on the lambdacyhalothrin showed that 4 out of 5 strains were tolerant and one is susceptible. It could be concluded that development of permethrin and lambdacyhalothrin resistance/tolerance in a number of strains of German cockroach was as the result of direct use of these later insecticides in human dwelling. Sumithrin resistance is unlikely related to use of such small amount of this compound in cockroach control programs; but it is likely related to uses of other pyrethroids and hence developing cross-resistance to sumitlirin

Genetics and mechanism of malathion resistance in anopheles stephensi from Bandar-Abbas and its cross resistance spectrum to DDT, dieldrin and pirmiphos-methyl

The genetics and mechanism of malathion resistance in the adults of An. stephensi [BAN-S], Was studied. Nine successive generations of malathion selection in the adults resulted in an increase in LTSO of about 3-fold. The crossing experiments indicated that the resistance is inherited as partially dominant character with no indication of sex linkage. The results of back-crosses suggested that probably more than one genetic factor are responsible for malathion resistance. Synergist study with TPP and PB indicated that the involvement of carboxyesterase as the main resistance factor in An. Srephensi. The cross- resistance spectrum of malathion resistance with pirimiphos- methyl, DDT and dieldrin were studied in the selected strain. The results did not show any relationship between resistances to malathion, DDTand pirimiphos- methyl. Dieldurin test on the selected and uselected strains showed that malathin resistance could increase dieldrin resitance