Journal of Arthropod-Borne Diseases最新文献

Background: The primary aim of this study is to determine infection to Leishmania parasites in the wild population of Phlebotomus caucasicus and Phlebotomus mongolensis using molecular methods in some important zoonotic cutaneous leishmaniasis foci in Iran.

Methods: Sand flies were collected from active colonies of rodent burrows from 16 trapping sites using sticky trap paper. In order to detect and identify of Leishmania parasites in females Ph. caucasicus and Ph. mongolensis, the Nested-PCR amplification of ITS2-rDNA region was performed to generate amplicon with 245bp for Leishmania major, 206bp for L. gerbilli and 141bp for L. turanica.

Results: In the current study we found DNA of different gerbil parasites such as L. major and L. turanica, and mixed infection of L. major/L. turanica in Ph. caucasicus and Ph. mongolensis. It should be noted that, in Iran, natural infection with Leishmania parasites is recorded for the first time in this study in Ph. mongolensis.

Conclusion: Both species of Ph. caucasicus and Ph. mongolensis not only may participate in the ZCL transmission cycle between reservoir hosts, but also results of this study support the role of these species as secondary vectors in the transmission of leishmaniasis to humans.

Background: In this study aimed to show the role of autophagy acting as a seesaw between apoptosis and necroptosis in certain vital organs under the effects of the Aegaeobuthus nigricinctus venom and different dosages of the Androctonus crassicauda antivenom administration in mice.

Methods: In the venom group (VG), mice (n= 6) were inoculated with 2LD₅₀ A. nigrocinctus venom. In the antivenom administered groups (AVG), the effects of the potency of the A. crassicauda antivenom were evaluated to have a neutralization effect against 20LD₅₀ of the A. nigrocinctus venom. After histopathological examination, expressions of mammalian target of rapamycin (mTOR) as an autophagy activator, receptor-interacting serine/threonine-protein kinase 3 (RIPK3) as a necroptosis activator, and caspase-3, caspase-9 as the markers of apoptotic cell death signals were evaluated by the immunoperoxidase method in addition to DNA in-situ fragmentations by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method.

Results: Only in VG, caspases and TUNEL expressions were found to be higher after the envenomation process in contrast to the elevated RIPK3 expressions. mTOR expressions remained almost stable in the organs. In AG, mTOR expressions were further increased in the 30LD₅₀ and 40LD₅₀ groups.

Conclusion: There were an increased mTOR expression and stabilized caspases and TUNEL expression in these subgroups, the RIPK3 expressions were found to be low when compared with all of the antivenom administration groups. Increasing doses of the antivenom drifts more the cells to autophagy while cell fate in organs under envenomation getting rid of apoptosis and necroptosis pathways.

Background: Firmly identification of Leishmania in Phlebotomus papatasi and understanding of natural transmission cycles of parasites in sand flies are important for treatment and local control.

Methods: Modified and developed method of High Resolution Melting (HRM) as a preferable technique was employed to accurate identification of Leishmania in sand flies from Iranian border with Iraq, by targeting cytochrome oxidase II (COII) gene and designing suitable primers. PCR products cloned into pTG19-T vector, then purified plasmid concentration was measured at 260 and 280nm wavelength. The melting curve plots were generated and DNA sequences were analyzed using Sequencher 3.1.1, CLC Main Workbench 5.5, MEGA 6, DnaSP5.10.01 and MedCalc® version 13.3.3 soft wares.

Results: Among about 3000 collected sand flies, 89 female Ph. papatasi were identified and two with L. major. In amplified fragment of COII gene among 611bp, 452bp had no genetic variations with low polymorphic sites (P= 0.001) and high synonymous (79.8%) as compare to non-synonymous sites (20.2%). Leishmania major was discriminated in Ph. papatasi with 0.84 °C melting temperature (T_m) and unique curve based on thermodynamic differences was an important criterion using HRM technique.

Conclusion: Subsequent war in Iraq made a high risk habitat for parasites transmission. It is important to discover accurate diagnostic procedures for leishmaniasis control.

Background: Dengue fever as a mosquito-borne disease, has rapidly spread due to climate change, globalization, and human behavior. Iran is prone to dengue fever, as its vector recently has been found in the country. This study aimed to assess predictors of dengue preventive practices based on Precaution Adoption Process Model (PAPM) factors in West Azerbaijan province, northwest of Iran.

Methods: This cross-sectional study conducted on 405 health professionals of communicable disease sector who were interested in study participation. Data-gathering instrument was an online researcher-made questionnaire consisting of demographic characteristics (11 items), questions based on PAPM, and dengue preventive practices (85 items). Content validity and reliability of the instrument, content validity ratio, content validity index, and Cronbach α were utilized, respectively. Descriptive, analytical, and regression analysis using SPSS and STATA were examined.

Results: Regression analysis revealed that awareness of appropriate actions for dengue prevention was a stronger predictor of preventive practice in borderline and appropriate categories (β= 4.09, p< 0.001) and (β= 4.42, p< 0.001), respectively. Among factors of PAPM, beliefs about precaution effectiveness and difficulty in borderline (β= 1.04, p= 0.04) and appropriate (β= 1.12, p= 0.03) groups had direct and significant relation with dengue preventive practice.

Conclusion: The highest mean score of beliefs about hazard likelihood and severity factor was related to dengue prevention. Therefore, theory-based interventions that address beliefs about precaution effectiveness and difficulty can lead to assistance in acting. To improve dengue preventive practices, a well-designed promotive intervention that addresses associated factors in a context-specific manner is essential.

Background: Fleas (Insecta: Siphonaptera) are considered as highly specialized bloodsucking on mammals such as dogs. The existence of three factors, namely a vast distribution area, different hosts, and digestive system with a specific mechanism for digesting blood has led to species of fleas who nourish from mammals be introduced as the potential vectors of diseases. The aim of this study was to assess Leishmania infantum natural infection of dog fleas in northwest Iran in 2018.

Methods: A total of 20 infested domestic dogs (Canis lupus familiaris) were randomly selected from 5 villages. Fleas were collected using brushing against dog hairs and fine forceps. Then, they were morphologically identified and preserved in ethanol for molecular assay. The kinetoplast DNA of the parasite was used for detection of Leishmania infantum using a semi-nested polymerase chain reaction (PCR) assay.

Results: The human flea, Pulex irritans, and the cat flea, Ctenocephalides felis were identified on 40% and 35% of dogs, respectively. The results of PCR indicated that L. infantum was found in the Ctenocephalides canis (75%) and C. felis (66.7%) collected from infected dogs. No leishmanial infection was observed in P. irritans.

Conclusion: It is concluded that fleas could be infected by Leishmania infantum, but maintenance of the parasite and their vectorial competence needs to be determined.

Background: Visceral leishmaniasis (VL) also known as Kala-azar is considered as one of the zoonotic infections in Mediterranean countries. The disease reservoir and vectors are dogs and sandflies respectively. Due to reported sporadic cases of Kala-azar in the past five years in Shahroud County, Semnan Province, Iran, this study aimed to investigate the status of this infection in this area and to determine its seroepidemiology to take required measurements for infection control and treatment.

Methods: This study was conducted on 504 subjects residing in seven villages in Shahroud County. Blood samples were randomly selected using the cluster sampling method and were collected from subjects aged up to 13 years old (90%) and adults over 13 years old (10%) from September to May 2019. After separating sera from whole blood, samples were subjected to direct agglutination test (DAT) to detect anti-Leishmania infantum antibodies. A range of 1:10 to 1:800 dilutions were prepared from the samples.

Results: Results of 1:800 titration indicated that no sample was positive for antibodies against L. infantum. After the secondary screening, 10 cases (1.98%) showed the antibody titer of 1:100, while four cases (0.79%) showed the antibody titer of 1:400. Of 14 cases with the L. infantum antibodies, all were detected from the children <13 years old. According to clinical findings, no patient was suffering from fever, weight loss, splenomegaly, hepatomegaly, and cachexia and therefore did not show the Kala-azar symptoms.

Conclusion: The results of the current study indicate that Kala-azar is not prevalent in Shahroud County.

Background: Scabies is referred to the infestation of skin by an ectoparasite, Sarcoptes scabiei. Having considerable financial consequences, this disease is a public health concern in several countries. In this review, we aimed to determine the current status of scabies in different provinces of Iran.

Methods: Google Scholar, PubMed, Scopus, Science Direct, Scientific Information Database (SID), Sci-explore, Civilica, Magiran, Iranian Research Institute for Information Science and Technology and Elmnet databases were searched to find the related data in the time period within 2000-2022. To have a better insight into the status of prevalence of scabies in Iran, a meta-analysis and meta-regression was performed.

Results: A total of 943 relevant studies were retrieved from the databases, and 62 eligible studies met all the needed criteria for inclusion in this systematic review. Scabies was investigated and reported in at least 22 and 21 provinces of Iran respectively. Most of the studies were conducted in Tehran, Razavi Khorasan, Hormozgan, Fars and Guilan Provinces. Positive samples of scabies belonged to humans, sheep, goats, dogs, rabbits, mice and gazelles. Meta-analysis showed that the overall estimated presence of scabies in Iran during 2000-2022 was 7% (95% CI 4.7-10.3%, P< 0.001).

Conclusion: Infestations due to S. scabiei in Iran occur in different geographical locations and different climates. As a neglected tropical disease, the literature about the burden of scabies in Iran is inadequate. The present review highlights the importance of development of comprehensive strategies for the diagnosis and control of scabies, especially the provinces with high infestation rates.

Background: Annually, thousands of scorpion stings and rare mortalities are recorded in the Kurdistan Region of Iraq. In the present study, we prepared a checklist for the geographical distribution of scorpion fauna composition, new localities data, and scorpion sting profile for the years 2019-2020 in the region.

Methods: Random field surveys for scorpion collection were carried out in 22 localities in the Kurdistan Region from June 2020 to October 2021. Clinical data related to scorpion stings in 2019 and 2020 were obtained from the medical records of public health offices in the region.

Results: In this survey, 166 specimens were collected. They were composed of seven scorpion species belonging to three families including: Buthidae, Hemiscorpiidae, and Scorpionidae. The collected species were Androctonus crassicauda, Compsobuthus matthiesseni, Hottentotta saulcyi, Mesobuthus mesopotamicus, Orthochirus fomichevi, Hemiscorpius lepturus, and Scorpio kruglovi. Moreover, three scorpion species comprising Buthacus tadmorensis, Hottentotta mesopotamicus, and Calchas anlasi were recorded in the previous study conducted in the Kurdistan region. In 2019-2020, 3726 scorpion stings were reported, with a peak in the summer season. Most of the patients were 15-49 years old. In the current study, medically significant scorpion species have been identified.

Conclusion: The outcome of the present work will increase the awareness of the Kurdish community regarding the distribution of dangerous scorpion species and consequently reduce their stings.

Background: Due to the outbreak of zoonotic cutaneous leishmaniasis (ZCL), a disease caused by Leishmania major and mainly transmitted by Phlebotomus papatasi, in Damghan City, Semnan Province, the probable vectors of the disease were investigated in the city from 20 March 2016 to 20 January 2018.

Methods: Sand flies were collected from indoors and outdoors biweekly by sticky traps in different parts of the city. The trapped sand flies were stored in 70% ethanol. They were identified and checked for Leishmania infections using nested-PCR method and specific primers; CSB1XR, CSB2XF, LiR, and 13Z.

Results: Overall, 1862 phlebotomine sand flies of Ph. papatasi (48.8%), Ph. andrejevi (8.3%), Ph. caucasicus (7.7), Ph. mongolensis (2%), Ph. sergenti (1.2%), Ph. alexandri (0.7%), Sergentomyia murgabiensis sintoni (29.3%), and Se. sumbarica (2%) were collected indoors (31.1%) and outdoors (68.9%). The highest and lowest numbers of collected sand flies were belonging to Ph. papatasi (48.8%) and Ph. alexandri (0.7%) respectively. 2.2% of the examined sand flies were shown to be infected with L. major and all were belonging to Ph. papatasi.

Conclusion: This study confirms the report of Ph. papatasi infection with L. major and also the existence of Ph. sergenti and Ph. alexandri, the potential vectors of L. tropica and L. infantum respectively, in Damghan City. According to the findings, it is necessary for health officials to plan and take action to prevent the occurrence of ZCL epidemic in the city as well as the occurrence of other forms of leishmaniasis.

Background: Culex theileri (Diptera: Culicidae) is a known vector of pathogens that cause dirofilariasis, Sindbis fever and West Nile fever in Iran. The species is one of the country's most abundant and widely distributed species.

Methods: In order to conduct a faunistic and bionomic study of mosquitoes, larval collection was carried out in Chahar Mahal and Bakhtiari Province of western Iran using dipping method.

Results: In total, some 2096 larvae of Cx. theileri were identified. Among the larvae, 1024 (48.9%) displayed aberrations and anomalies in the development of cranial seta 1-C (preclypeal seta). Morphological aberrations and anomalies of seta 1-C in the third- and fourth-instar larvae and abdominal terga of the adults of Cx. theileri collected in Iran are discussed and illustrated.

Conclusion: More studies are needed throughout the distribution of Cx. theileri to analyze the variation of the species, especially using both morphological and molecular data.