Vol 17 No 3 (2023)

Original Article

  • XML | PDF | downloads: 68 | views: 63 | pages: 197–205

    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.

  • XML | PDF | downloads: 105 | views: 95 | pages: 206–213

    Background: The house fly, Musca domestica, is vector for pathogens and parasites and causes economic damage to livestock by reducing forage conversion efficiency, negatively impacting weight gain and milk production. It has shown resistance to multiple insecticide classes. The aim of this research was to determine the susceptibility levels of seven­teen field M. domestica strains to thiamethoxam, a neonicotinoid insecticide, in Türkiye.
    Methods: Insecticide susceptibility of the house flies to thiamethoxam was determined using the WHO glass jar meth­od. A probit analysis program was used to determine LD50 values, and then the resistance ratios were compared with insecticide-susceptible strain.
    Results: All strains were ≥18.5-fold resistant to thiamethoxam. The data showed that 10 out of 17 strains had either high or very high resistance levels. Our findings revealed that house flies from solid waste landfills in Samsun, Ankara, and Kocaeli exhibited higher resistance ratios compared to those found in animal shelters. Conversely, in Gaziantep, Antalya, İzmir and Erzurum, the exact opposite trend was observed. Regarding the LD50 values among solid waste stor­age areas, the lowest rate was obtained from Gaziantep (0.72 gr ai/m2), and the highest rate was obtained from Ankara (9.35 gr ai/m2). Furthermore, regarding the LD50 values among animal shelters, the lowest was obtained from Samsun (0.37 gr ai/m2), and the highest was obtained from Denizli (21800 gr ai/m2).
    Conclusion: The use of integrated control systems is recommended for controlling house fly populations, including insecticide class rotations for preventing, or at least, delaying the onset of resistance.

  • XML | PDF | downloads: 101 | views: 371 | pages: 214–228

    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.

  • XML | PDF | downloads: 103 | views: 128 | pages: 229–240

    Background: It is possible to identify drugs and poisons present in cadavers by analyzing blowfly larvae and pupae col­lected during forensic autopsies. The main purpose of this study was to use Lucilia sericata’s larvae and pupae to iden­tify drugs and poisons present in human cadavers.
    Methods: In an investigation, immature L. sericata fed meat treated with methamphetamine (MA) at various concentra­tions (45, 90, and 180 ng/mg) were analyzed to detect MA. Acetylation derivatization and liquid-liquid extraction (LLE) were used as sample preparation methods prior to gas chromatography-mass spectrometry (GC-MS) analytical instru­men­tation to find MA.
    Results: According to this study, L. sericata can be used in toxicological testing to identify MA in a host body. All L. seri­cata larval stages, particularly the third stage larva, pupa and empty pupa tested were positive for MA. Larvae in their first instar produced weak peaks. The L. sericata post-feeding instar following the 45 ng/mg treatment showed the highest MA concentration. For the first time, derivatization using the acetylation approach was used to prepare samples, and successfully, excellent results were obtained.
    Conclusion: Low quantities of MA can be easily found in immature fly samples using GC-MS. It is important to ana­lyze all samples including human tissues and insect samples, for postmortem drug testing. They can be utilized to find entire MA before they are excreted in excretory samples such as urine. Also, third instar larvae are a great and reliable sample for toxicological study.

  • XML | PDF | downloads: 76 | views: 54 | pages: 241–256

    Background: Bed bugs are blood-feeding insects and are an important urban pest. Bed bugs are nocturnal insects and hide in cracks in walls and beds during the day. The study aims to: (1) determine the bed bugs species that infest Iraq, their infestation source, and their distribution; (2) determine the level of awareness and concern regarding bed bugs among the Iraqi community.
    Methods: Between 2020 and 2021, a survey of bed bug infestation dynamics was conducted in 18 infested sites located in major cities across eight governorates. The 23-item online survey was distributed over social media to Iraqi citizens between June and July 2022 to survey on their familiarity with bed bug habitat, medical significance, transmission, pre­vention, control measures, and concerns.

    Results: There were a total of 1104 bed bugs collected. Based on the morphological characteristics, bed bugs collected from eight Iraqi governorates are identified as Cimex hemipterus. Besides, a high rate of bed bug infestation was ob­served in workers' dormitories. The online questionnaire was answered by 1843 respondents and based on the feedback, most respondents (55.3%) have no awareness of bed bug infestations, while around 43.8% are somewhat concerned about bed bug infestations in Iraq.
    Conclusion: Only tropical bed bugs, C. hemipterus were found in all sampled sites. Bed bug infestations are mainly caused by migrant workers and the reuse of second-hand furniture and clothing. The results suggest that the Iraqi gov­ernment should organize more proper demonstrations on bed bug awareness for the public.

  • XML | PDF | downloads: 60 | views: 45 | pages: 257–271

    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.

  • XML | PDF | downloads: 54 | views: 54 | pages: 272–286

    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.

  • XML | PDF | downloads: 53 | views: 63 | pages: 287–298

    Background: There are few studies analyzing the epidemiological characteristics and clinical features of arthropod bites and stings, emergency department (ED) admission rate and cost burden. This study aimed to evaluate the clinical features and ED burden of such cases.
    Methods: We retrospectively analyzed 954 patients who presented to ED after exposure to arthropods. The demograph­ic and clinical characteristics, treatment rates, consultation and hospitalization requirements, and costs were evaluated.
    Results: The rate of presentation to the ED after exposure to arthropods was 0.36%. Among the identifiable insects, 25%, 22%, 5%, 3% and 1% patients were exposed to bees, ticks, scorpions, spiders, and centipedes, respectively. Of the included patients, 51% were male and the mean age was 39.4±14.8 years. Exposure to arthropods was most commonly seen in the summers (45%). Local and systemic toxicities developed in 11% and 1% of patients, respectively. Further examinations were requested in 50% of cases and 83% of cases received treatment. 4% of cases were hospitalized, and 21% were prescribed medicines.. The average cost per patient of exposure to spiders, scorpions, centipedes, ticks and bees were 45.5, 28.3, 17.3, 12.6, and 10.1 US Dollars, respectively. The total cost of ED for all patients was calculated as $12,694.65.
    Conclusion: We believe that a better understanding of the characteristics and prevalence of arthropod bites and stings will have a positive impact on primary prevention, health resource planning and reducing the burden on EDs by improv­ing people's knowledge and practices to reduce the incidence of bites and stings.