Vol 16 No 2 (2022)

Original Article

  • XML | PDF | downloads: 131 | views: 189 | pages: 84–96

    Background: Androctonus crassicauda is the most medically relevant scorpion and understanding its genetic forms is essential for improvement of anti-venom sera, and risk management of scorpionism. Present study was designed to identify the variations of mitochondrial genes in different populations of A. crassicauda.

    Methods: Adults of A. crassicauda were collected from Zanjan Province during 2016–2017. Genomic DNA of samples was extracted and fragments of mitochondrial 16S, COI and ND1 genes were amplified and some of the amplicons were sequenced. Haplotype of samples were identified by multiple alignment of sequences, then phylogenetic trees of haplo­types were constructed.

    Results: Fragments of 352bp, 618bp and 680bp were amplified from 16S, COI and ND1 genes respectively. Nucleotide sequence in COI fragments was conserved, however, five haplotypes with some specific polymorphic sites were detect­ed in 16S and ND1 fragments. Haplotype I was dominant and found in all areas. Other haplotypes were rare and limited to specific regions. Analysis of the phylogenetic trees inferred from 16S and COI genes, confirmed a strong positive correlation between geographic and genetic distance.

    Conclusion: Mitochondrial COI, 16S and ND1 genes were detected suitable for identifying the population structure. Five genotypes were found using 16S and ND1 genes. To prepare and improve the anti-venoms quality, additional stud­ies are necessary to identify the toxin electrophoretic profile and geographical/ecological niche models of these geno­types in future.

  • XML | PDF | downloads: 137 | views: 198 | pages: 97–107

    Background: Ticks are vectors of many pathogens that involve various important diseases in humans and animals, they have several diverse hosts consequently can retain a diverse group of indigenous microbes, from bacteria to fungi. Little is known about the prevalence and diversity of tick microflora colonizing the midgut and their effects on ticks and their interaction. This information is important for development of vector control strategies.

    Methods: This study was carried out in northern Iran during autumn 2019. Ticks, Ixodes ricinus caught alive on the bodies of domestic animals in the fall. The tick homogenate was prepared. The identification of fungal isolates was car­ried out according to a combination of macro and microscopic morphology and molecular sequencing. Pathogenic bac­teria of the family Borreliaceae, Francisella tularensis, Borrelia burgdorferi and Coxiella burnetii were tested by real-time PCR.

    Results: A total of 133 mature I. ricinus ticks were collected from domestic animals, including 71.5% cattle and 28.5% sheep. The tick frequency rates were 87.21% for Mazandaran, 8.28% for Golestan and 4.51% for Gilan Provinces. Total prevalence of fungal tick contamination was 53.4% (75/133) of which Trichoderma harzianum (57%) was the most prevalent species followed by Aspergillus spp. (42%), Mortierella alpine (19%) and Penicillium polonicum (14%). All tick samples were negative for three pathogenic bacteria including Francisella tularensis, Coxiella burnetii, and Borre­lia burgdorferi by real-time PCR analysis.

    Conclusion: These results show a first picture of the microbial diversity of ticks and highlight the importance of micro­biota and their role in host-pathogen interaction.

  • XML | PDF | downloads: 114 | views: 178 | pages: 108–123

    Background: Gujarat State has been witnessing large scale urbanization, in last two decades, resulting changes in local environment and microclimate may have also influenced the resting, feeding habits and development of Anopheles cu­licifacies sensu 1ato. Therefore, a systematic longitudinal study was undertaken to know the bionomics of An. culicifa­cies s.l. in present study.

    Methods: The study was conducted in four sentinel villages in Kheda and Panchmahal Districts. The mosquitoes rest­ing indoors and outdoors were collected in early morning hours, using mouth aspirator, pyrethrum space spray and light traps. Mosquito landing collections on human volunteers was carried out from dusk to dawn. Species composition, abundance, seasonal prevalence, resting behavior (Endophily and Exophily), sibling species composition, vector poten­tial and insecticide susceptibility status of malaria vectors was studied.

    Results: Six Anopheles species were collected, An. subpictus s.l. was the predominant species followed by An. culicifa­cies s.l., a known malaria vector was resting indoor and zoophagic behaviour. Anopheles culicifacies, sibling species B (89%) was found. The sporozoite rate (%) and entomological inoculation rate in Kheda was 2.33%, 3.09 per bite/ per­son/annum and they were 1.05% and 0.475 bite/person/annum in Panchmahal, respectively. Anopheles culicifa­cies s.l. was found possible resistance to alpha-cypermethrin.

    Conclusion: Anopheles culicifacies s.l. showed endophillic, zoophagic behaviour and found possible resistance to al­pha-cypermethrin. Early biting behaviour of An. culicifacies s.l. in this area is a cause of concern. Therefore, there is need for frequent monitoring and evaluation of vector control measures in order to achieve the elimination target of ma­laria in this area.

  • XML | PDF | downloads: 130 | views: 160 | pages: 124–135

    Background: Various arthropods, including Rhipicephalus sanguineus and Ctenocephalides felis felis have been sug­gested as secondary vectors of Leishmania spp. many years ago. This study was conducted to determine zoonotic cuta­neous leishmaniasis (ZCL) PCR positivity of reservoir hosts and their ectoparasites for Leishmania spp. in Segzi plain in Esfahan Province from October 2016 to October 2017.

    Methods: Microscopic examination and nested PCR were used to detect and identify Leishmania spp. isolated from rodents' ear and ectoparasites, and then, the results were confirmed by two methods, PCR-restriction fragment length polymorphism and sequencing.

    Results: Totally, 93 rodents (92 Rhombomys opimus and one Nesokia indica) and nine different species of ectoparasites (n=527) including fleas, mites, and ticks were collected during different seasons in the study area. Fourteen R. opimus were positive for Leishmania spp. by microscopic examination while one N. indica and 77 R. opimus were positive by nested PCR. The infection rate of rodents with Leishmania major and L. turanica was 39.79% (n=37) and 15.05% (n=14), respectively. Mixed natural infections with L. major and L. turanica were seen in rodents. Moreover, 72.22% of fleas (39/54), 75.0% of mites (5/8), and 100% of tick nymph (1/1) were PCR positive for Leishmania parasites.

    Conclusions: The highest rate of infection with L. major and L. turanica in R. opimus populations was observed in summer and spring, respectively. It is suggested that the role of L. turanica and the probable role of ectoparasites in the epidemiology of disease should be investigated. A Xenodiagnostic test is recommended for future study.

  • XML | PDF | downloads: 126 | views: 181 | pages: 136–147

    Background: Anopheles stephensi is an important malaria vector mosquito in Iran and other western Asian countries. In many human communities, plant products have been used traditionally instead of synthetic pesticides for mosquito control due to their minimal hazardous effects. Teucrium polium, known popularly as felty germander, has been intro-duced in Persian Medicine (PM) as an insect repellent from a long time ago.
    Methods:
    The present study was undertaken to evaluate repellent and larvicidal activity of dichloromethane (DCME-TP) and ethanolic extracts (EE-TP) of T. polium against An. stephensi under laboratory conditions. The possible chemi-cal components of the extracts were also investigated through gas chromatography/mass spectrometry (GC-MS) tech-nique.
    Results:
    Based on the results, DCME-TP showed better repellent activity than EE-TP with 56.67 and 28.33 % protec-tion, respectively. Larvicidal activity of DCME-TP with 49.41% mortality was also higher than EE-TP (20.24%). The main identified constituents of DCME-TP were long chain alkanes, phenol, aromatic ester, oxaspiro and triterpenoid. While phenolic and aliphatic acid were only the identified components in EE-TP. It is notable that lupeol was detected in DCME of T. polium for the first time.
    Conclusion:
    DCME-TP can be considered as a new herbal candidate to control An. stephensi mosquitoes. Further stud­ies are required on this extract for the fractionation and identification of the active compounds, and the evaluation of their bioactivity in the laboratory and field.

  • XML | PDF | downloads: 121 | views: 163 | pages: 148–158

    Background: Phlebotomus and Sergentomya are distributed in the old-world regions and transmit leishmaniases through mammalian and reptile hosts. Cutaneous leishmaniasis (CL) is one of the most important diseases in Iran. Irani­an sand flies belong to three Oriental, Palearctic, and Afrotropical Regions. Fars Province is located in Palearctic, but southern parts are affected Oriental region situations on phglebotomine population variety. Therefore, a comprehensive study was required on the vectors of the disease in this Province.

    Methods: Regarding the approved role of the environmental factors in creating the fauna and distribution of living crea­tures, the “de martonne climate method” was used, and the climate was noticed as an important environmental factor for the determination of vector distribution. Accordingly, 14 sampling sites were selected from 10 foci in different climates of Fars Province. 19648 sand flies were collected from the studied areas in this Province during 2016.

    Background: Phlebotomus and Sergentomya are distributed in the old-world regions and transmit leishmaniases through mammalian and reptile hosts. Cutaneous leishmaniasis (CL) is one of the most important diseases in Iran. Irani­an sand flies belong to three Oriental, Palearctic, and Afrotropical Regions. Fars Province is located in Palearctic, but southern parts are affected Oriental region situations on phglebotomine population variety. Therefore, a comprehensive study was required on the vectors of the disease in this Province.

    Methods: Regarding the approved role of the environmental factors in creating the fauna and distribution of living crea­tures, the “de martonne climate method” was used, and the climate was noticed as an important environmental factor for the determination of vector distribution. Accordingly, 14 sampling sites were selected from 10 foci in different climates of Fars Province. 19648 sand flies were collected from the studied areas in this Province during 2016.

    Results: Phlebotomus papatasi and Se. antennata were the most frequent species, which were caught from in/outdoor areas. Phlebotomus sergenti and Ph. alexandri were caught from both Palearctic and Oriental zones but were more prevalent in the cold semi-arid climate of the Palearctic zone. Moreover, they were not caught from the hot desert and summer Mediterranean climates of the Oriental zone.  

    Conclusions: It seems that Ph. papatasi as the main vector of CL could be well distributed in different climates in Fars. Moreover, some species like Ph. sergenti preferred especial climates in the Palearctic zone. Therefore, these data could be helpful to control leishmaniases more efficiently.

  • XML | PDF | downloads: 132 | views: 256 | pages: 159–172

    Background: Phlebotomine sand flies are vectors of Leishmania species, the causative agents of leishmaniasis in the world. Present study aimed to evaluate the bioecological aspects of sand flies in different ecotopes in Sari County, north of Iran.       

    Methods: Sand flies were collected from four villages in mountainous, forest, plain and peri-urban areas monthly using sticky traps in May–October 2016. Mounted specimens were identified using valid identification keys under optical microscope. The Arc GIS 10.5 software was applied for showing the distribution of sand flies. Shannon-Weiner, Simp­son and Evenness species diversity indices were calculated.

    Results: Generally, 334 specimens were captured and identified, namelly Phlebotomus kandelakii, Ph. papatasi, Ph. major, Ph. sergenti, Ph. longiductus, Ph. halepensis, Ph. tobbi, Sergentomyia dentata, Se. theodori, Se. sintoni, Se. an­tennata and Se. sumbarica. The most common species was Ph. kandelakii (n= 128, 38.32 %). The highest Simpson in­dex (0.81) and abundance (N= 141) were recorded in the mountaineous area. Shannon diversity index was higher in the forest (H'= 1.53) and the highest evenness index was in the plain area (J'= 0.93). The highest richness (S= 9) and Shan­non indices (H'= 1.57) were observed in June.

    Conclusions: Phlebotomus kandelakii, Ph. sergenti, Ph. tobbi, Ph. longiductus, Se. theodori, Se. antennata and Se. sumbarica were recorded for the first time in the study area. Since some species are incriminated for leishmaniasis transmission, further studies are required in the northern regions of Iran to timely control measures planning.

Case Report