Search

Background: The aim of this study was to evaluate different concentrations of deltamethrin combined with formulated piperonyl butoxide (PBO) synergist on various surfaces against the wild strain of Anopheles stephensi, the main malaria vector in Southern Iran under semi-field condition. Methods: Four concentrations of deltamethrin WG 25% (Tagros) and PBO 800EC-UV (Endura) were prepared and sprayed on the pre-designed surfaces in accordance with WHO alliance line of the IRS Micronair®. The WHO’s recommended bioassay kit and method was used during this study. Results: Comparing the mortality rate of mosquitoes, the results showed a significant difference between months after treatment of IRS (Indoor Residual Spraying) (P< 0.05) but didn't show any significant differences between days during the first and second months (P> 0.05). Statistical test revealed a significance difference between mortality rate of mosquitoes in exposing to concentrations of 1 and 4 (P< 0.05) which demonstrated effect of synergizing PBO on mortality rate. Conclusion: This research as the first semi-field trial on deltamethrin added to different concentrations of formulated PBO for IRS, indicates that deltamethrin+10X PBO is more effective than other concentrations. Therefore, using synergists can be suggested as a new tool for prevention of pyrethriod resistance, although more studies are recommended. [ABSTRACT FROM AUTHOR]

Background: Linear dermatitis is endemic in Iran where most cases occur in the Caspian Sea coast and Fars province. The disease is caused by beetles of the genus Paederus which are active from early spring to beginning of autumn although its incidence rises from May to August. The classic taxonomy of Paederus spp. is based on the male genitalia that is very complex and needs expertise. In this study, we report a DNA-based method to discriminate Paederus fuscipes and Paederus littoralis (=syn: P. lenkoranus, P. ilsae). Methods: Type specimens were collected from north and south of Iran. Molecular typing of the species was performed using restriction fragment length polymorphism (RFLP) analysis of polymerase chain reaction (PCR)-amplified fragments of mtDNA-COI. Results: Sequence analyses of the data obtained in this study showed significant DNA polymorphisms. There were 89 substitutions between COI sequences of the two species. The mtDNA-COI fragment comprises several useful species-specific restriction sites comprising HaeIII that could result in distinctively different species-specific PCR- RFLP profiles. The HaeIII enzyme cuts the 872 bp PCR amplicon of P. littoralis into 737 and 100 bp and two small nonvisible bands whereas it does not cut P. fuscipes amplicon into fragments. Conclusion: This study demonstrates that molecular typing is useful method and allows one to differentiate between two species and is recommended for discrimination of other Paederus species, which morphologically are indistinguishable or very difficult to be distinguished. [ABSTRACT FROM AUTHOR]

Background: There are nearly 1000 species of Phlebotomine sand flies in 6 genera, of which only two, Phlebotomus in the old world and Lutzomyia in the new world are medically important. Globally, leishmaniasis prevalent in 98 countries and affects estimated 12 million people with almost two million new cases per year. Some rural areas of Azarshahr District in East Azarbaijan Province have been reported to be endemic for visceral leishmaniasis. This study is the first attempt to determine the species diversity and density in a new focus of visceral leishmaniasis in Azarshahr District, East Azarbaijan Province, Iran. Methods: Sand flies were collected form indoor and outdoor biweekly using sticky traps. Diversity index of the collected sand flies within different villages were estimated by the Shannon-Weaver. Results: The activity of the sand flies extended from April to October with one peak in August. Diversity of sand flies within study area were estimated as 0.917, 1.867, 1.339, 1.673, and 1.562 in Almalodash, Jaragil, Segaiesh, Amirdizaj, and Germezgol Vvillages, respectively. Conclusion: Identifying the diversity and seasonal abundance of the collected species is of importance for prediction of the period of maximum risk for leishmaniasis transmission and for the successful implementation of a control program. Species diversity is one of the most important factors in ecological studies. [ABSTRACT FROM AUTHOR]

Background: Aquatic insects are the major groups of arthropods that spend some parts of their life cycle in the water. These insects play an important role for transmission of some human and animal diseases. There is few information about the aquatic insects fauna of Iran. Methods: To study the aquatic insects fauna, adult, nymphal and larval collections were carried out from different habitats using the standard technique in Zayandeh Roud River, Isfahan Province,central Iran, during summer 2011. Results: In total, 741 speimens of aquatic insects were collected and morphologically identified. They include 7 families and 12 genera representing 2 Orders. The order of Diptera (92.31%) and Coleoptera (7.69%). The families Culicidae, Syrphidae and Chironomidae from Diptera order, Gyrinidae, Dytiscidae, Haliplidae, Hydrophilidae from Coleoptera order were identified. Conclusion: Some aquatic insects play an important role for transmission of human and animal diseases. These insects also are important for biological control. Therefore ecological study on aquatic insects can provide information about ecology of insects in an area for any decision making. [ABSTRACT FROM AUTHOR]

Background: Eco-faunistic studies are inevitable step in environmental researches. Aquatic organisms like caddisflies are known as biological indicators for water quality assessment and water resource management. They have special role for energy flow in the freshwater habitats as food web and food chain among aquatic creatures. Methods: In addition to an extensive literature review on Iran Caddisflies, a field study was carried out in Lavasan river flows in north east of Tehran to collect aquatic insects using D-frame nets and or direct search on stone beneath. The water quality was measured using analytical method. Results: Literature revealed record of 62 trichopterid species in the country comprising 14 families. The most abun- dant species belonged to the Hydropsychidae. Herein we report presence of the Annulipalpian Hydropsyche sciligra H Malicky, 1977 in the study area. Habitat water quality of H. sciligra resembled human drinkable water. However presence of snail, Physa acuta and fish Capoeta buhsei in the water sampling area indicated inferior quality. Conclusion: From ecological point of view caddisfly larvae are predators of most important medical vectors like mosquitoes, blackflies and midges. Also they are useful and important indicator for monitoring physicochemical effects in the nature, so that they can be used for bio-monitoring program. From medical point of view, wing hairs or other body parts of caddisflies can be inhalant and contact allergens in Trichopterists and in sensitive individuals who come in contact. [ABSTRACT FROM AUTHOR]

Background: The Long-lasing insecticide impregnated nets (LLINs) is considered as an effective tools for malaria vector control. The aim of this study was to evaluate the residual efficacy of alpha-cypermethrin long lasting impregnated nets (LLIN-Interceptor®) against Anopheles stephensi using tunnel test. Methods: The wash-resistance of Interceptor® nets were assessed under laboratory conditions using tunnel test. Females of An. stephensi were released into the tunnel and then they were provided blood meals from guinea pigs. Bed nets were washed according to the standard procedure up to 20 times. The bioefficacy indicators such as inhibition of bloodmeal from experimental animal, knockdown, irritancy rate, survival rate, entry index and mortality were calculated. Results: It induced 90-100% mortalities in the population of An. stephensi up to 15 washes. The KT 50 values reduced from 73.47 to 26.30 minutes in unwashed in comparison to one washed, respectively. The mean of mortality rate of blood-feeding inhibition and entry indexes was reached to 91.6%±2.8, 87.0±3.4 and 24.9±2.8 respectively after 20 washing. Conclusion: This net could provide a good personal protection against malaria vectors and could induce relatively high mortality, inhibit the blood-feeding as well as reduce the entry rates of female mosquitoes even after several washes. [ABSTRACT FROM AUTHOR]

Background: 2TThe growing population and increasing needs to agricultural products increased use of pesticides resulting in contamination of the environment, including water. The purpose of this study was to 2Tdetermination2T of 2Tpesticide residues2T in agricultural water resources in Barzok city of Kashan in 2011. Materials and Methods: 2TThis study as a descriptive and cross-sectional study that was conducted at spring season. That totals of 135 samples of the agricultural water resources of Barzok were 2Tcollected2T randomly and mixtures from different stations. After extraction and preparation of samples, the 2Tpesticide residues2T were determined by using the HPTLC (High Performance Thin Layer Chromatography) devices and CATS4 software. Finally, obtained data were analyzed by using ANOVA statistical 2Tmethods2T. Results: 2TThe results of this study showed that maximum amount of diazinon and chlorpyrifos has been 22.43 and 11.79 ppm respectively, and the2T pesticide residues2T have declined gradually overtime of (p<0.001).Furthermore, after a month 95.9% of Chlorpyrifos and 88.8% of diazinon is degraded. Conclusion: 2TAccordingly, the remaining of diazinon and chlorpyrifos after a month of spraying was higher than determined limited standards. Because Chlorpyrifos is broken down rapidly more than diazinon, it is recommended that besides educating farmers on the proper use of pesticides, unnecessary contact with the water resources of this region must stop at least one month after spraying. [ABSTRACT FROM AUTHOR]