Vol 17 No 1 (2023)

Review Article

  • XML | PDF | downloads: 296 | views: 242 | pages: 1–27

    Background: Controlling of Aedes aegypti and Ae. albopictus, vectors of five important mosquito-borne diseases, is known as the most effective method to prevent the transmission of arboviruses to humans, but the emergence of insecti­cide resistance is threat for control and prevention of vector borne diseases. A better understanding of mosquito re­sistance to insecticides will help to develop more effective methods to control insecticide resistance in mosquito vectors.

    Methods: Worldwide geographical distribution of insecticide resistance in Ae. aegypti and Ae. albopictus by the availa­ble papers and map of the data for carbamates, organochlorines, organophosphates, pyrethroids, microbial and insect growth regulator insecticides were reviewed. Article data published up to December 2022 were investigated by search­ing the following databases: "Google Scholar", "PubMed", "Scopus", "SID" and "Web of Knowledge".

    Results: The results showed that the susceptibility and resistance status of Ae. aegypti and Ae. albopictus to insecticides in the world is very diverse.

    Conclusion: Due to the importance of Ae. aegypti and Ae. albopictus in the transmission of mosquito-borne arbovirus­es, resistance management should be given more attention worldwide to prevent insecticide resistance in the arbovirus vector and replace the new approach for vector control.

  • XML | PDF | downloads: 123 | views: 139 | pages: 28–35

    Background: The Covid-19 pandemic that caused by the infection with the novel Coronavirus SARS-CoV-2 has re­vealed individual and global vulnerabilities all over the world. Many countries that had been struggled with arthropod-borne diseases (VBDs) are now embroiled in another challenge caused by COVID-19 pandemic. The situation that pos­es major obstacles 1) by misdiagnosis 2) delay in early and appropriate treatment of VBDs 3) difficulties in applying regular strategy for vector control and prevention methods and finally 4) irregularity in financing supports. Given the possible scenario of syndemics, it is important to plan integrated and combined measurement with the maximum partic­ipation of the people and health authorities. Here, the impact of COVID-19 pandemic on some major arthropod-related diseases will be discussed.

    Methods: To access the collective data all related databases such as Science direct, PubMed, Elsevier, Google scholar, as well WHO web page were searched with key words “arthropoda-related diseases, COVID-19 with the name of each individual disease”.

    Results: The results showed that the management, control, and treatment of most important arthropod-related diseases could be delayed due to COVID-19 pandemic.

    Conclusion: Dealing with COVID-19, it is crucial to consider the other main killers such as malaria, dengue fever, etc. more especially in vulnerable populations by greater political, financial and global commitment. Continued surveillance will be essential to monitor for any possible changes.

Original Article

  • XML | PDF | downloads: 142 | views: 160 | pages: 36–50

    Background: Phlebotomus sergenti, the proven vector of Leishmania tropica, the causative agent of anthroponotic cu­taneous leishmaniasis, is widely distributed in Morocco. Previous works using molecular markers (Internal Transcribed Spacer 2 rDNA and Cytochrome B mtDNA) hypothesized the existence of multiple closely related populations of sand fly species (cryptic species) that would exhibit distinct vectorial capacities. This work studies morphotypic diversity using traditional and geometric morphometry analyses carried out on Ph. sergenti's wings from central Morocco, where active L. tropica transmission occurs for 30 years.

    Methods: Descriptive characteristics (size and shape) of the right wings were measured in Ph. sergenti’s specimens collected from fourteen stations in central Morocco. Both traditional and geometric morphometry methods were used to analyse geographic variations in Ph. sergenti wing’s size and shape.

    Results: These analyses support the existence of distinct Ph. sergenti populations, enlightening significant phenotypic variations of Ph. sergenti’s wings, regarding their size and shape, depending on geographic origin. In addition, tradi­tional and geometric morphometric analyses of the wing’s length, centroid size, β, ɵ, and γ distances allowed clear dis­crimination of Ph. sergenti sub-populations.

    Conclusion: These data pinpoint the adaptative ability of Ph. sergenti to local environmental conditions. Additional studies are now required to further shed light on the genetic structure of Ph. sergenti populations in Morocco.

  • XML | PDF | downloads: 140 | views: 161 | pages: 51–62

    Background: Aedes (Stegomyia) albopictus was found for the first time in 2011 on the Black Sea coast in Russia, and dur­ing 2011–2019, the species expanded over two climate zones Cfa and Csa.

    Methods: Here, we studied the sequence diversity of the mitochondrial cytochrome c oxidase I (COI) gene, 1317–1433bp in length. In total, 131 specimens of Ae. albopictus sampled from 21 locations in Russia and Abkhazia were examined.

    Results: Two of the six identified mitochondrial haplotypes were detected for the first time. Four COI haplotypes were shared by at least two studied local populations. The most prevalent H1 and H2 haplotypes dominated in all the sampled localities in the Cfa zone. The H3 haplotype was prevalent in the Csa zone. Other haplotypes were rare. Phylogenetic analyses, spatial isolation and limited gene flow revealed that the samples from the Csa zone differed significantly from those from the Cfa zone.

  • XML | PDF | downloads: 162 | views: 181 | pages: 63–71

    Background: Cockroaches are one of the most important carriers of pathogenic microorganisms. Therefore, the pres­ence of cockroaches in public places, especially in hospitals, homes, and restaurants, is dangerous, and threatens the health of society, people, and the environment. The aim of this study was evaluation of bacterial contamination of cock­roaches and the sensitivity of these bacteria to various antibiotics, captured from Khorramabad City, Iran

    Methods: This descriptive cross-sectional study was performed on 150 cockroaches collected from hospital environ­ments, homes, and restaurants in Khorramabad. The outer surface of the cockroaches was washed with physiological sa­line. The suspension was centrifuged for 5 minutes at 2000rpm. Isolation and identification of bacteria was performed using phenotypic methods. Antibiotic susceptibility testing was performed by disk diffusion method according to Clini­cal and Laboratory Standard Institute (CLSI) guideline.

    Results: A total of 100 American cockroaches (66.66%), 28 B. germanica (18.66%) and 22 Blatta orientalis (14.66%) were identified. In total, 97.33% of the collected cockroaches were infected with bacteria. The most bacterial infection of the cockroaches was Escherichia coli, coagulase-negative Staphylococci and Bacillus respectively. The overall re­sults of the antibiogram test showed that the identified bacteria were resistant to cephalothin, ampicillin, cefotaxime, and kanamycin antibiotics, semi-sensitive to ciprofloxacin and sensitive to tetracycline, gentamicin, nitrofurantoin, Tri­methoprim/sulfamethoxazole, and Chloramphenicol.

    Conclusion: Infection of cockroaches with pathogenic bacterial agents in hospital, residential, and restaurant environ­ments, as well as the observation of bacterial resistance to some common antibiotics is worrying.

  • XML | PDF | downloads: 112 | views: 168 | pages: 72–82

    Background: Anopheles stephensi is a major vector of malaria in some parts of the world. A standard method for de­termining resistance in adult mosquito populations is the bioassay test recommended by the world health organization (WHO). The papers used in this method have an expiry date. This study aimed to determine the effectiveness of outdat­ed susceptibility test papers for use in insecticide resistance monitoring programs.

    Methods: Beech and Bandar Abbas strains of An. stephensi were reared in the insectary. Permethrin 0.75%, Deltame­thrin 0.05%, and Bendiocarb 0.1% impregnated test papers prepared by Universiti Sains Malaysia were used. Probit analysis was used to analyze the results and prepare time-mortality regression lines of LT50 and LT90.

    Results: There was a difference in the mortality of both tested strains of An. stephensi was exposed to all tested insecti­cides. Both expired and not expired Permethrin and Deltamethrin papers induced 100% mortality at the diagnostic time (60min), but their insecticidal properties were reduced gradually in serial times. The highest efficacy of test papers was in the first trimester after the expiry date and decreased over time.

    Conclusion: At the diagnostic time of 60 minutes, the mortality rate of both dated and expired papers was 100% in the pyrethroid insecticides, even three years after expiry dates, if stored in the package provided by the producer, in a re­frigerator. This value was reduced to less than 100% in the expired papers of Bendiocarb comparing the dated papers that induced 100% mortality.

  • XML | PDF | downloads: 148 | views: 185 | pages: 83–93
    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.

  • XML | PDF | downloads: 192 | views: 206 | pages: 94–104

    Background: A combined morphological and molecular survey was performed to determine the agent of human linear dermatitis Paederus Fabricius, 1775 (Coleoptera: Staphylinidae, Paederinae) species composition in Mazandaran Prov­ince in the Caspian Sea coast in northern Iran, where most of linear dermatitis cases of the country occurred.

    Methods: Altogether, 397 Paederus specimens were collected from May to August 2021 and classified using morphological characters and ITS2-rDNA sequence analysis.

    Results: Morphological investigation revealed that all the specimens were Paederus fuscipes. ITS2 polymerase chain reaction (PCR) direct-sequences and the profiles of restriction fragment length polymorphism (RFLP) derived from digestion of PCR products by HinfI, HpaII, and SalI enzymes were identical confirming the morphological results, implying that all specimens belonged to a single taxon.

    Conclusion: Paederus fuscipes (Fabricius, 1775) is considered the dominant taxon and responsible for linear dermatitis in Ma­zandaran Province. To our knowledge, we have provided the first molecular typing of Paederus beetles at the species level, suggesting that ITS2-rDNA characterization is an alternative tool for species discrimination of Paederus spp.