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Background: Anopheles stephensi, a malaria‐transmitting mosquito species, has developed resistance to various insecticides such as DDT, Dieldrin, Malathion, and synthetic pyrethroids. To combat this issue, the World Health Organization (WHO) suggests using Actellic®300CS and Icon®10CS for Indoor Residual Spraying to tackle pyrethroid‐resistant mosquitoes. The aim of this research project was to evaluate the susceptibility of An. stephensi to certain insecticides at the diagnostic concentration + intensity 5x diagnostic concentration (5XDC) assays in Iran and to study the lasting effectiveness of Actellic®300CS and Icon®10CS against this particular malaria vector. Methods: This study assessed the susceptibility of An. stephensi populations in southern Iran to various insecticides, including deltamethrin 0.05%, DDT 4%, malathion 5%, bendiocarb 0.1%, a synergist assay with PBO 4% combined with deltamethrin 0.05%, and an intensity assay using 5x the diagnostic concentration of deltamethrin (0.25%) and bendiocarb 0.5%. Laboratory cone bioassay tests were conducted to determine the residual effectiveness of Actellic®300 and Icon®10CS insecticides on different surfaces commonly found in households, such as cement, mud, plaster, and wood. The tests were carried out following the WHO test kits and standard testing protocols. Results: The An. stephensi populations in Bandar Abbas were found to be susceptible to malathion 5% and deltamethrin 0.25% (5XDC), but exhibited resistance to DDT, standard concentration of deltamethrin, and both standard and intensity concentrations of bendiocarb. In laboratory cone bioassay tests, An. stephensi mortality rates when exposed to Actellic®300CS and Icon®10CS on different surfaces remained consistently more than 80%. Actellic®300CS achieved more than 80% mortality on all substrates for the entire 300‐day post‐spraying period. Conversely, Icon®10CS maintained mortality rates more than 80% on plaster and wood surfaces for 165 days and on mud and cement surfaces for 270 days post‐spraying. Both Actellic®300CS and Icon®10CS demonstrated 100% mortality within 72 h of each test on all surfaces throughout the entire 300‐day post‐spraying period. Conclusion: The study shows the varying levels of resistance of An. stephensi Bandar Abbas population to different insecticides and demonstrates the consistent performance of Actellic®300CS in controlling these mosquitoes on various surfaces. The findings suggest that long‐lasting CS formulations may be more effective for malaria vector control compared to the current options. Further research is needed to validate these findings in field settings and assess the impact of these insecticides on malaria transmission. [ABSTRACT FROM AUTHOR]

Background:Phlebotomus papatasi (Diptera: Psychodidae) is the main vector of zoonotic cutaneous leishmaniasis. Wolbachia is a symbiotic alphaproteobacteria of arthropods that can be involved in susceptibility or resistance. This study aimed to investigate the relationship between Wolbachia and Deltamethrin susceptibility/resistance in Ph. papatasi. Deltamethrin filter papers (0.00002%) were used to test sand fly field collected from southern Iran. After the test, PCR amplification of the Wolbachia surface protein gene (wsp) was used to measure Wolbachia infection rate in the killed, surviving, and control groups. Result: The rates of infection by Wolbachia strain (wPap, super group A) differed between killed (susceptible) and surviving (resistant) Ph. papatasi specimens. The rate of Wolbachia infection in susceptible individuals was more than twice (2.3) (39% vs. 17%) in resistant individuals with the same genetic background. This difference was highly significant (p < 0.001), indicating a positive association between Wolbachia infection and susceptibility to Deltamethrin. In addition, the results showed that Deltamethrin can act as a PCR inhibitor during detection of Wolbachia in Ph. papatasi. Conclusion: Results of this study show that Wolbachia is associated with Deltamethrin susceptibility level in Ph. papatasi. Also, as Deltamethrin has been identified as a PCR inhibitor, great care must be taken in interpreting Wolbachia infection status in infected populations. The results of this study may provide information for a better understanding of the host-symbiont relationship, as well as application of host symbiosis in pest management. [ABSTRACT FROM AUTHOR]

Background: Indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs) are two core interventions for control and prevention of malaria infection. This descriptive cross-sectional study aimed to determine the knowledge and practices of women regarding malaria and its preventive measures in a malarious area in the Jask County, southeast of Iran. Methods: Data was collected from 400 households through a two-stage random cluster sampling method in six villages. Pre-tested structured questionnaire was used to collect data. During the survey, visual observations were also made by the interviewers to check use of LLINs and IRS. The data were analyzed by SPSS software version 21. Results: The majority of households had a high level of knowledge about symptoms (98%, n=392) and transmission (74.5%, n=298) of malaria. The main preventive measures against malaria were: LLINS (39.5%, n=158), IRS (32%, n=128), and screens on doors/windows (16.7%, n=67). In addition, participants with primary or higher educational level reported that they practice more malaria preventive measures, compared to those who were illiterate (OR=3.3, 95% CI= 1.6–6.6, p=0.0001, Table 6). In spite of positive perceptions about IRS and LLINs, only 35.5% (n=142) and 17% (n=68) of households used IRS and LLINs, respectively. Conclusion: According to the results of this study, despite a high level of knowledge about malaria and its preventive measures, a small number of participants use LLINs and IRS for malaria prevention. Therefore, implementation of effective educational interventions is recommended to improve preventive practices against malaria in the study area. [ABSTRACT FROM AUTHOR]

Background: Phlebotomus papatasi (Diptera: Psychodidae) is the main vector of zoonotic cutaneous leishmaniasis (ZCL) in Iran. The nonstandard use of pesticides against pests, particularly in agriculture, indirectly has caused the development of resistance and, consequently, the threat of control measures in ZCL endemic areas. Up to 2023, several reports of resistance in Ph. papatasi have been declared in the Old World. The purpose of this study was to measure the lethal time (LT50 and LT90) of Ph. papatasi sand flies in the ZCL endemic center of Esfahan to DDT and deltamethrin insecticides. Methods: Sand flies were collected in Borkhar and were tested using WHO adult mosquito test kit against DDT 4% and deltamethrin 0.0002%. The sand fly’s survival was recorded during exposure time in 225, 450|, 900, 1800, and 3600- seconds’ intervals for DDT and Deltamethrin and they were allowed to recover for 24 hours. Then LT50 and LT90 were analyzed using probit software. Phlebotomus papatasi were identified using morphological keys and other sand flies’ species were excluded from the analysis. Results: The insecticide against female Ph. papatasi revealed hundred percent mortality when exposed to DDT 4% and deltamethrin 0.0002%. The LT50 and LT90 were 19.32 and 22.74 minutes for DDT 4% and 39.92 and 51.33 minutes for deltamethrin 0.0002% respectively. Conclusion: Results of this study revealed that Ph. papatasi is still susceptible to DDT and deltamethrin. This data provides valuable knowledge to implement effective control strategies against ZCL main vector and help to manage insecticide resistance in the region. [ABSTRACT FROM AUTHOR]

Anopheles stephensi is an efficient vector of malaria parasites in Iran. Despite its importance in malaria transmission, there is a scarcity of accurate predictive models of its rates of development at different temperatures. A laboratory colony of An. stephensi, collected from Bandar Abbas County, southern Iran, was established, and all its developmental stages were maintained in temperature-controlled incubators so that the water temperature set at 5, 8, 10, 12.5, 14, 28, 38, 39.5, 42, and 45(±0.2) °C for different treatments until subsequent adult emergence. The Lower and Upper Developmental Temperatures (LDT and UDT) and the growth degree-day (GDD) were calculated for each development stage. A 12-mo population dynamics survey of the larvae and adults of An. stephensi was performed in 3 malaria-endemic villages (Geno, Hormoodar, and Sarkhoon) of Bandar Abbas County, and the obtained data were matched with the constructed GDD model. Based on the field meteorological and dynamics data, the model was verified in the field and used to determine the appropriate date to start spraying. The LDT was determined to be 8.19, 9.74, 8.42, 5.6, 13.57, and 10.03 °C for egg hatching, first, second, and third ecdysis, pupation, and eclosion events, respectively. The UDT was 38 °C for all developmental stages. The thermal requirement for the development of all immature stages of An stephensi was determined to be 187.7 (±56.3) GDD above the LDT. Therefore, the appropriate date to start residual spraying is when the region's GDD reaches 187.7 (±56.3). Given the climatic conditions in Bandar Abbas County, it is expected that the first activity peak of adult An. stephensi would be in March. Field observations showed that An. stephensi activity starts in February and peaks in March. The GDD model can provide a good estimate for peak An. stephensi activity and indicate the optimal deployment time of residual spraying operations against the multiplication and development of malaria parasites inside the vector. [ABSTRACT FROM AUTHOR]

Background: Drosophila melanogaster flies are smooth, low upkeep and safe model organisms, they can be effortlessly used in different fields of life sciences like genomics, biotechnology, genetics, disease model, and Wolbachia-based approaches to fight vectors and the pathogens they transmit. Methods: Fruit fly specimens were collected in 25 districts (14 provinces) of Iran and their morphological recognition was proven by molecular analysis based on sequence homology of mitochondrial COI barcode region. Essential information and specific requirements were provided for laboratory rearing of D. melanogaster. Results: Drosophila melanogaster colonies were found in 23 out of 25 districts. Also, five related species coincident with D. melanogaster were reported in this study including D. ananassae/D. parapallidosa, D. hydei, D. repleta, Zaprionus indianus (Diptera: Drosophilidae), and Megaselia scalaris (Diptera: Phoridae). The Iranian D. melanogaster molecular signature and their rearing techniques have been described here. The complete life cycle, from (egg to adult), takes approximately 8 days at 25 °C. Some biological points have been presented with highlighting capturing, rearing, culturing, and embryo collection along with primitive recognition and segregation between females and males have been presented. A recipe for culture media and the quantity of various ingredients have been provided. Conclusion: This is the first report on the D. repleta and D. ananassae/D. parapallidosa species for the country. Results of this study provide efficient and effective rearing procedures which are requirement for both small-scale for facilitating entomological research and large-scale use in justifiable vector control management such as disease model or Dengue control. [ABSTRACT FROM AUTHOR]

Background: Cockroaches play a role in the mechanical transmission of microbial pathogens. This study was designed to determine the isolated bacteria and their susceptibility to conventional antibiotics from brown-banded cockroach, Supella longipalpa, in Qom province, central Iran. Methods: In this cross-sectional study, brown-banded cockroaches were bred in an insectary and caught from hospitals of Qom. The samples were taken from the surface and alimentary canal and then cultured on microbial culture media; next, grown specimens were identified using differential culture media. Finally, after performing diagnostic tests and identifying the bacteria species, their susceptibility to various antibiotics was evaluated. Results: A total of 120 adult cockroaches from the insectary and hospitals were included in the study. Ten bacterial genera were found; nine were Gram-negative and one was Gram-positive. The genus Klebsiella, Enterobacter, Staphylococcus, Citrobacter and Hafnia were isolated only from the hospital strain. On the other hand, Pseudomonas and Escherichia from both groups and other species such as Salmonella, Proteus and Shigella were isolated only from laboratory strains. The highest antibiotic resistance among Gram-positive cocci and Gram-negative bacilli were 100.0% and 98.1% for ampicillin and Ceftazidime, respectively. Conclusion: The results of this study showed that various pathogenic bacteria harbored by brown-banded cockroaches. Moreover, it was found that most of these bacteria belong to the Enterobacteriaceae family, which can be pathogenic and thus threaten human health. [ABSTRACT FROM AUTHOR]

Background: Anopheles stephensi is the main vector of malaria in Iran. This study aimed to determine the susceptibility of An. stephensi from the south of Iran to bendiocarb and to investigate biochemical and molecular resistance mechanisms in this species. Methods: Wild An. stephensi were collected from Hormozgan Province and reared to the adult stage. The susceptibility test was conducted according to the WHO protocols using bendiocarb impregnated papers supplied by WHO. Also, field An. Stephensi specimens were collected from south of Kerman and Sistan and Baluchistan Provinces. To determine the G119S mutation in the acetylcholinesterase (Ace1) gene, PCR-RFLP using AluI restriction enzyme and PCR direct-sequencing were performed for the three field populations and compared with the available GenBank data. Also, biochemical assays were performed to measure alpha and beta esterases, insensitive acetylcholinesterase, and oxidases in the strains. Results: The bioassay tests showed that the An. stephensi field strain was resistant to bendiocarb (mortality rate 89%). Ace1 gene analysis revealed no G119S in the three field populations. Blast search of sequences revealed 98–99% identity with the Ace1 gene from Pakistan and India respectively. Also, the results of biochemical tests revealed the high activity of non-sensitive acetylcholinesterase, alpha and beta-esterase in the resistant strain compared to the susceptible strain. No G119S was detected in this study additionally the enhanced enzyme activity of esterases and acetylcholinesterase suggesting that resistance was metabolic. Conclusion: The use of alternative malaria control methods and the implementation of resistance management strategies are suggested in the study area. [ABSTRACT FROM AUTHOR]

Background: Zoonotic cutaneous leishmaniasis is a major public health problem in Iran with the main vector of Phlebotomus papatasi. The use of entomopathogenic fungi for biological control of the vector is a potential substitute for the current methods which are being used. The purpose of the current study was to assess the virulence of two local isolates of Beauveria bassiana (OZ2 and TV) against Ph. papatasi. Methods: To perform the bioassay test, fungal suspensions were applied for every stage of the sand fly life cycle. The mortality rate, longevity, and number of eggs laid were determined. Also, the probability of fungal survival on the surface of rodent’s body was assessed. Results: The longevity of infected adult sand flies with both isolates of B. bassiana was significantly lower (P< 0.05) in comparison to the negative control. The estimated Lethal concentration 50 (LC50) values for adult female and male sand flies treated with OZ2 isolate were 1.4×106 and 2.2×107 conidia/ml, respectively, while they were 6.8×106 and 2.3×108 conidia/ml for TV isolate, respectively. Both isolates of B. bassiana exhibited nonsignificant mortality rates in sand fly larvae and pupae and fecundity rate (P> 0.05). According to our findings for both isolates, the fungus continued to spread throughout the surface of the rodent's body for 144 hours after spraying. Conclusion: The current study demonstrated that both isolates of B. bassiana have considerable biological control capacity against adult sand flies. [ABSTRACT FROM AUTHOR]

Background: The German cockroach, Blattella germanica (Insecta: Blattodea, Blattellidae), which occurs widely in human buildings, is a small cockroach species. Cockroach control chemical pesticides are toxic to the environment, and it is sometimes impossible to prevent them. Controlling Blattella germanica through ultrasonic waves can be efficient and less dangerous for the environment. Methods: In this study, the repellency and lethal effect of ultrasonic waves on male and female German cockroaches was tested in a twin glass cubic chamber at laboratory condition. The wave frequencies tested ranged from 20 to 100kHz with 5kHz steps. A signal generator generated these frequencies, and the piezoelectric transmitter of these ultrasonic waves was positioned in the chamber's center on the upper side. Results: Fisher's test showed that there was the greatest repellency effect in both male and female at frequencies of 35 and 40kHz. According to the results of the regression test, the most lethal effect is at the frequencies of 40 and 75kHz. Conclusion: The operating ultrasonic frequencies investigated in this study can be used to repel and kill German cockroaches as pests endangering human health and environment. [ABSTRACT FROM AUTHOR]

Medicinal plants are used as control measure against mosquito bites. Efficacy, protection time and the effective dose of specimens were assessed on Anopheles stephensi. The malaria vector were reared under insectary condition, plants were collected from different parts of the country and identified and certified based on the morphological characters. The chemical composition of the volatile constituents was evaluated by gas chromatography–mass spectrometry (GC-MS). The repellent activity of extracted essential oils was evaluated against adult female An. stephensi by using the animal-bait technique on white rabbits (Oryctolagus cuniculus). Major component of the essential oils from each area according to climatic conditions indicated 36 compounds in M. longifolia, Cis-β-guaiene 42%, Cubenol 22%, and (Z)-3-hexenol 11.2% in Armand district, as well as 13 compounds with 8-cedren-13-ol 85.5%, Cis-ascaridole 4.2%, and Oplopanone 3% in Shah-manzar were the major components of the essential oil at autumn season. Mean protection time and the efficacy of specimens from different climates were 5.9, 6.6 and 2.3, 3.1 and 2.3, 3.3 and 3.0, 3.3 h, respectively. ED50 and ED90 values for the same specimens were calculated 1.48, 10.46, and 2.94, 24.02, and 5.26, 31.83, and 13.68, 84.23 μl/cm2, respectively. A total of 65, 11, 29, and 24 chemical compounds were isolated. Humid temperate cold area had the highest protection time. It can be considered as an appropriate herbal repellent against malaria vector. [ABSTRACT FROM AUTHOR]

Background: Ticks are blood-sucking ectoparasites of many vertebrates and act as vectors of a wide range of vectorborne diseases. Alongside pathogens transmission, ticks also cause economic losses in animal industry such as production loss, physical damage, anemia, and poisoning. This study aimed to determine the fauna, geographical distribution and seasonal activity of ticks collected from animals in Lorestan Province, west of Iran. Methods: Ticks were collected from domestic animals including cattle, sheep, goats, chickens, turkeys, pigeons, as well as wild animals such as jackals in 2017–2018. Then, they were identified based on morphological characteristics using valid identification keys. Results: Out of a total of 706 ticks, 433 (61.33%), 104 (14.73%), 33 (4.67%) and 136 (19.26%) ticks were collected in spring, summer, autumn and winter, respectively. In terms of hard ticks, 4 genera and 6 species were identified: Hyalomma asiaticum (22.80%), Hyalomma anatolicum (3.68%), Hyalomma marginatum (2.40%), Rhipicephalus sanguineus (0.84%), Dermacentor marginatus (1.13%), and Haemaphysalis sulcata (0.64%). Additionally, two genera and four species fell into soft ticks: Argas persicus (60.48%), Argas reflexus (6.65%), Ornithodoros canstrini (0.70%) and Ornithodoros erraticus (0.42%). There was significant variation in the seasonal activity and abundance of ticks in different seasons but in the tick abundancy among different regions. Conclusions: The present study provides a perspective of the distribution status of ticks in Lorestan Province, their seasonal activity and the likelihood of emergence of related diseases. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Fauna and larval habitat characteristics studies on mosquitoes are important tools to identify the breeding places of the vectors and management of the control strategies. This study was done to provide data on Culicidae fauna, larval habitat characteristics and identifying potential vectors of West Nile virus in Lorestan Province, west of Iran. Methods: Culicidae mosquitoes were collected at three counties and nine site stations from Lorestan Province, west of Iran in 2017. Adult mosquitoes were collected using human and animal bite collection methods, New Jersey and CDC light traps and pit shelters by aspirator. Larva were collected by dipping method. RT-PCR technique was employed for detection of the West Nile virus among mosquito’s samples. Results: 4805 mosquitoes were collected from three counties and nine sites in Lorestan Province during June–October 2017, including 4363 adults and 442 larvae. The most abundant species collected from all counties in both adult and larval stages were Culex pipiens (49.10%), Cx. theileri (31.82%), Anopheles maculipennis (11.09%), An. superpictus (2.66%), An. stephensi (2.12%), Cx. perexiguus (1.89%), An. dthali (1.17%) and An. sacharovi (0.15%) respectively. West Nile virus was detected in none of mosquitoes examined. Conclusion: The results of this study revealed that arbovirus vectors such as Cx. pipiens along with Cx. theileri and Cx. perexiguus are well adapted to a broad range of habitats and different climatic conditions in Lorestan Province. That necessitates further routine surveillance of arboviral infections. [ABSTRACT FROM AUTHOR]

Background: Due to undesired environmental impact of insecticides as well as resistant of vectors to them, the development of organic and natural insecticides has been more considered. In the current study, we developed nanoemulsion of eucalyptus and investigated lavicidal activity of it against malaria vector, Anopheles stephensi and Culex pipiens under laboratory as well as semi-field conditions. Methods: An optimized nanoemulsion was prepared by mixing Eucalyptus oil, Tween 80 and ethanol at ratio of 1:2:1.5 in distilled water, then, stirred for 20 minutes at room temperature. The product was then used for bioassay tests against 3-4th instar larvae of Anopheles stephensi as well as Culex pipiens. Furthermore, a semi-field trial was carried out to evaluate larvicidal activity of nanoemulsion of eucalyptus. Results: Nanoemulsion of eucalyptus showed significantly high lavicidal activity comparing with bulk eucalyptus essential oil. The LC50 and LC90 value of nanoemulsion against An. stephensi were 111.0 and 180.8 ppm respectively and 29.5 and 73.7 ppm for Cx. pipiens, respectively. In the semi field condition, the Nanoemulsion of eucalyptus decreased 1-2nd instar larval density of Culicines and Anophelines to 90.1% and 85.2%, respectively. Conclusion: The nano formulation of eucalyptus oil showed high larvicidal activity. Therefore, nanoemulsion of eucalyptus oil can be used as an eco-friendly larvicide against mosquitoes. [ABSTRACT FROM AUTHOR]

Background: Due to the confirmation of the presence of the novel coronavirus in the feces and municipal sewerage system, and the feeding of domestic insects from fecal matter, as well as the ability of these insects to mechanically transmit microbes from the sewerage system. This study was aimed at molecular evaluation of the novel coronavirus infection isolated on cockroaches and flies collected from Kamkar-Arabnia Hospital in Qom City, Iran. Methods: Totally, 18 samples; (12 samples cockroaches and 6 flies) from the external surface of cockroaches and houseflies as well as their digestive system were prepared. After designed and synthetized exogenous heterologous internal control, the RNA was extracted to investigate the contamination of these samples with the novel coronavirus. To detect the virus, the E and RdRp genes were identified. Results: Investigation of coronavirus E gene using the multiplex one-step qPCR technique on the collected samples showed an amplification plot in CT= 35.70 related to the internal surfaces of cockroaches collected from the treatment and sick room of the hospital. Also, the design of internal control to ensure the accuracy of the extraction process was successful. Conclusion: According to the findings of the present study regarding detecting the presence of the coronavirus infection in the digestive system of domestic insects such as American cockroaches and considering their ability to mechanically transmit viruses, it is recommended to control the domestic insects that are in close contact with humans in crowded places such as hospitals and health centers during the Covid-19 pandemic. [ABSTRACT FROM AUTHOR]

Background: Culex pipiens complex is considered as a vector of some important diseases such as West Nile fever, equine encephalitis, Rift valley fever, St. Louis encephalitis, Elephanthiasis and avian malaria in the world. The main measure for vector control is using insecticides. High use of insecticides caused resistance in the populations. The aim of this study was to review the status of insecticide resistance in the vector. Methods: Insecticide resistance in this species was found by the available papers and map of the data for carbamates, organochlorine, organophosphates, pyrethroids, microbial and insect growth regulator insecticides were done. An intensive search of scientific literature was done in “PubMed”, “Web of Knowledge”, “Scopus”, “Google Scholar”, “SID”, and related resources. Results: Results showed that a wide variety of resistance to different insecticides in the country. Due to importance of this species in transmission of diseases. Discussion: resistance management strategies should be further considered to prevent from in secticide resistance and replacement of novel approach for vector control. [ABSTRACT FROM AUTHOR]