Search

Background Evaluation of insect succession patterns is a scientific method to estimate the time elapsed since death. Several studies have shown that ante-mortem intake of opioids affect maggot growth rate. However, there are few published data that investigate the effect of ante-mortem opioid use on insect succession patterns. Therefore, the main purpose of this research was to investigate the effect of methadone on the succession patterns of insects on rabbit carcasses during the spring and winter of 2019. In the present study, the H-null hypothesis represents the dissimilarity between the successional waves of species from testing and control carcasses (H0: P: 0). Results During this study, 15 and 13 insect species were collected from carcasses during the spring and winter, respectively. The most dominant species during the both seasons were Chrysomya albiceps and Calliphora vicina. These two species preferred to lay eggs on the control carcasses earlier than the treated carcasses. Lucilia cuprina was observed only from the remains of untreated carcasses, while Saprinus chalcites and Necrobia rufipes were recorded only from the remains of treated rabbits. Samples indicate that 11.8% of the insects were members of the Coleoptera. Permutation analyzes based on the Mantel test were 0.647 ± 0.16 (P = 0.009) and 0.693 ± 0.16 (P = 0.003) for the similarity of the species between treated and untreated carcasses in the spring and winter, respectively. Permutation analyzes for the two most dominant fly species (Ch. albiceps and C. vicina) between the treated and untreated carcasses in the spring and winter were 0.515 ± 0.15 (P = 0.05) and 0.491 ± 0.14 (P = 0.09), respectively. Conclusion The results revealed that the overall pattern of insect succession was similar between the treated and untreated rabbit carcasses. However, the patterns of succession of Chrysomya albiceps and Calliphora vicina differed slightly between treated and untreated carcasses, and this could have an effect on the PMI min estimate.

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

Introduction: Zoonotic cutaneous leishmanianisis is one of most important health problem in theworld and the disease has been reported from more than 88 countries with 350 million people at the riskof it .The disease has been widespread in several parts of islamic republic of Iran. Sand flies(phlebotominae) are the vectors of the disease that transmit of parasites from the infected rodents tohuman. Knowledge on ecology of Sand flies can help us to design of disease control program. Determineof fauna and monthlyonthly activity of Sand flies was the main objects of this study.Material and Methods: This survey was performed as an experimental and practical study. It wascarried out in Damghan district of Semnan province during 2008. Sand flies were collected from indoorsand outdoors using sticky traps twice in month from early April to late November.Results: Totally 6110 sand flies (6 species of Phlebotomus and 2 species of Sergentomyia) werecollected and identified from indoors (2146) and outdoors (3964). Activity of sand flies were started inApril and ended in October with two peaks in May and September. The dominant species werePhlebotomus papatasi.Conclusion: High density of Phlebotomus papatasi as the dominant specimen indicates that, thisspecies can be the main vector of disease. Collection of P. caucasicus, P.mongolensis and P. ansarii fromrodent burrow show that they can play as the secondary role to transmitting of disease among rodentreservoirs. Dissection of sand flies for finding of parasites and following of them by molecular methods isnecessary to confirmation of proven vector(s). Control of rodents, environmental sanitary as well aspersonal protections and insecticide impregnated bed nets was suggested to prevention of disease.

Two repellents includes Iranian and Merck dimethyl phthalate (DMP) were evaluated against Anopheles stephensi and Culex pipiens, using American Society for Testing and Material (ASTM) standard ED 951-83 procedure, a free choice method based on the variable dose-fixed time. Also a modified of ASTM method we used for determination of effective dosages of the repellents. In ASTM method there were no significant differences between the two repellents (Iranian and Merck's DMP) as indicated by the ED50 and ED95 values (p > 0.05). But, there were significant differences in repellent sensitivity between An. stephensi and Cx. pipiens at the ED95 level. In modified ASTM method there were no significant differences between the two repellents against An. stephensi, as indicated by the ED50 values (p > 0.05). But, there are significant differences between the two repellents against Cx. pipence based on ED50 value. Results of this study showed that the Iranian synthesized DMP has necessary potential and specificity to compare with Merck manufactured product.