Vol 14 No 1 (2020)

Original Article

  • XML | PDF | downloads: 439 | views: 581 | pages: 1–7

    Background: Aquatic insects include groups of arthropods which at least one step of their life happens in water. Some of these insects play an important role in the transmission of various diseases to human and animals. Because there is a lit­tle information about the fauna of aquatic insects in Iran, this study was aimed to collect and identify aquatic insects in northwestern Iran.
    Methods: A descriptive cross sectional study was performed in July 2017 in Rivers of three villages of Osku County of East Azerbaijan Province, northwestern Iran. The specimens were collected using different methods including D frame net-collector, standard mosquito dipper, Sweep Netting and plastic pipette. The collected specimens were identified based on the systematic keys of aquatic insects.
    Results: Totally 285 samples were collected. Four orders including Diptera, Hemiptera, Ephemeroptera and Coleoptera were identified. Collected samples belonged to seven families of Tipulidae, Chironomidae, Corixidae, Culicidae, Hy­dro­philidae, Baetidae and Dytiscidae. The most predominant family was Culicidae belonging to order Diptera. Culiseta longiareo­lata was the most frequent species collected in the study area.
    Conclusion: Aquatic insects usually play an important role in the food chain of animals and some species of them act as predators and play an important role in the biological control of vectors. Therefore, more studies are required to carry out in the field of aquatic insects.

  • XML | PDF | downloads: 394 | views: 543 | pages: 8–16

    Background: Visceral and cutaneous leishmaniasis are common in some areas of Iran and consider as health problems. Phlebotomus alexandri has been incriminated as a suspected vector for the both form of leishmaniasis.
    Methods: This study was carried out in 4 western provinces of Iran. Sand flies were collected using sticky traps and light traps from indoor and outdoor resting places. Nested PCR was employed to detect Leishmania parasites among collected sand flies.
    Results: Seven hundred and twenty two P. alexandri females were collected and pooled in 179 batches. Results of nested PCR showed, out of 9 samples from East Azerbaijan Province, only one sample was infected by Leishmania infantum. Of 34 individual and pooled samples from Kermanshah Province, only one pooled sample was infected with Leishmania major and among 30 individual and pooled samples in Fars Province, five specimens were infected by L. major, L. infantum, Leishmania donovani and Leishmania tropica. Furthermore, out of 108 individual and pooled samples from Khuzestan Province, 10 samples showed infection with L. major and L. infantum.
    Conclusion: The results of this study showed that P. alexandri is more active in hot zones than in moderate zones and this species may be considered as a permissive species.

  • XML | PDF | downloads: 289 | views: 505 | pages: 17–28

    Background: Leishmaniases are parasitic diseases caused by Leishmania species and transmitted by the bite of sand flies. The genus Lutzomyia and Phlebotomus of sand flies are known to be the responsible vector for transmitting almost all Leishmania species to humans. The detection of Leishmania DNA in species of the genus Sergentomyia, in different regions, suggests their likely role in Leishmania transmission.
    Methods: Our objective was to determine the potential geographical distribution of Sergentomyia minuta, the most dominant Sergentomyia species in Morocco, using ecological niche modeling.
    Results: The results showed the widespread geographical distribution of S. minuta in Morocco, specifically in northern and central Morocco where visceral and cutaneous leishmaniasis foci occur. There were six abiotic factors affecting the distribution of S. minuta whose annual precipitation, precipitation seasonality and precipitation of driest month as the most important ecological variables of the model.
    Conclusion: A positive statistical correlation between human leishmaniasis cases and S. minuta abundance was noted suggesting the potential involvement of S. minuta in local Leishmania transmission cycles.

  • XML | PDF | downloads: 379 | views: 441 | pages: 29–37

    Background: The common bed bug, a nocturnal bloodsucking insect, is known as a human parasite and public health problem in the world. The prevalence and geographical dispersion of bed bug in Ahvaz City, southwest of Iran was measured.
    Methods: Spatial distribution of Cimex lectularius was determined by surveying 520 houses in 62 areas of Ahvaz City in 2017. Some information like as infested points, the concern level of the residents and allergic reaction to the insect bite were registered in a form using the secondhand instrument.
    Results: According to the spatial distribution map, of 62 areas, 27 of them are infested with bed bugs. Infestation is scattered throughout the city, but its focus is on the east of the Karun River. The most bed bug infestation was in Asi­abad followed by Manbaab areas. Prevalence of bed bug infestation estimated 9.61% in Ahvaz city. It was 5.4% and 11.6% in apartments and single houses, respectively. The lowest and highest infestation rates based on its source were 1.35% and 9.03% in wallpaper and cracks and crevices, respectively. Bedroom and sitting room were the main harbor­ages for bed bug in the houses. The majority of residents who had bitten by a bed bug showed various allergic reactions like redness skin, papules, vesicles, pustules and blisters. Most of the people in the infested houses (62%) were very concern about bed bug infestation.
    Conclusion: Public education and increasing the knowledge of people can lead to successful management, prevention and elimination of this nuisance pest.

  • XML | PDF | downloads: 253 | views: 362 | pages: 38–46

    Background: Mediterranean form of visceral leishmaniasis (VL) is endemic among some provinces of Iran. The pre­sent study was designed to determine the prevalence of canine visceral leishmaniasis (CVL) in the owned dogs of the rural areas of Alborz Province near Tehran as the capital of Iran.
    Methods: This study conducted on 303 owned dogs that selected using a stratified random sampling method. The direct agglutination test (DAT) was used to determine the frequency of Vl. The spleen biopsy was taken from the serology-positive dogs for the confirmation of CVL in the suspected dogs. Nested PCR and sequencing methods were used to determine the type of Leishmania species in the dogs which were parasitological positive.
    Results: Overall, the DAT results of 9 dogs (2.97%, CI: 1.57–5.55) showed anti Leishmania antibodies at titers ≥ 1:320 indicating VL infection. One dog (0.33%, CI 95%: 0.06–1.85) showed clinical signs and symptoms of VL. There was a significant correlation between the positive cases of CVL and rural area (p< 0.001). The Leishmania was observed in the impression smears that were prepared from spleen biopsy of five the studied dogs. Leishmania infantum were con­firmed in all them using nested–PCR assay. The sequence analysis of all five isolates was 95% similar to L. infantum.
    Conclusion: This study shows that domestic cycle of L. infantum has been established in rural areas of Alborz province where located near Tehran as capital city of Iran. It is necessary to increase the awareness and monitoring of the disease periodically.

  • XML | PDF | downloads: 267 | views: 408 | pages: 47–55

    Background: This study aimed to develop a loop-mediated isothermal amplification (LAMP) assay for the rapid detec­tion of tick-borne relapsing fever in resource-limited areas.
    Methods: A set of six primers were designed based on the conserved regions of the Glycerophosphodiester phos­phodiesterase (glpQ) gene of Borrelia species. For sensitivity assay, serial dilutions of a recombinant plasmid contain­ing a 219bp sequence of the glpQ were prepared and used as the template DNA. The LAMP reactions containing the six primers and the reagents required for amplification were incubated at 60–65 °C for 60min in a Loopamp real-time tur­bidimeter. For the specificity test, DNA from 14 other bacteria were included in the assays, and double-distilled water was used as the negative control. Also, DNA from dried blood spots (DBSs) of spirochetemic mice, and blood samples from relapsing fever-suspected patients were examined by the LAMP along a Borrelia-specific nested PCR that targets the rrs-rrl-IGS region.
    Results: The LAMP detected as low as 90glpQ copies in reactions. The primers reacted with DNA from DBS of spi­rochetemic mice showing spirochete concentrations of ≤ one per a 1000X microscopic field. In clinical samples, the LAMP assay showed a higher sensitivity compared to nested-PCR. The LAMP specificity was 100%, as the primers did not react with other bacteria DNA.
    Conclusion: The high sensitivity and specificity of the test, along with the simplicity of the DNA extraction procedure, make the LAMP a reliable and adaptable tool for the diagnosis of tick-borne relapsing fever in rural endemic areas.

  • XML | PDF | downloads: 354 | views: 518 | pages: 56–67

    Background: Cutaneous leishmaniasis (CL) is a dermal and parasitic disease.. The aim of this study was to determine the effect of environmental and climate factors on spatial distribution of CL in northeastern Iran by utilizing remote sensing from 20 March 2016 to 19 March 2017.
    Methods: In this ecological study, the data were divided into two parts: The descriptive data on human CL cases were gathered from Communicable Diseases center of Iran. The remote sensing techniques and satellite imagery data (TRMM, MODIS-Aqua, MODIS-Terra and AMSR-2 with spatial resolution 0.25°, 0.05°, 5600m and 10km) of environ­mental and climate factors were used to determine the spatial pattern changes of cutaneous leishmaniasis inci­dence.
    Results:
    The incidence of CL in North Khorasan, Razavi Khorasan, and South Khorasan was 35.80 per 100,000 people (309/863092), 34.14 per 100,000 people (2197/6,434,501) and 7.67 per 100,000 people (59/768,898), respectively. The incidence of CL had the highest correlation with soil moisture and evapotranspiration. Moreover, the incidence of dis­ease was significantly correlated with Normalized Difference Vegetation Index (NDVI) and air humidity while it had the lowest correlation with rainfall. Furthermore, the CL incidence had an indirect correlation relation with the air tem­perature meaning that with an increase in the temperature, the incidence of disease decreased.
    Conclusion: As such, the incidence of disease was also higher in the northern regions; most areas of North Khorasan and northern regions of Razavi Khorasan; where the rainfall, vegetation, specific humidity, evapotranspiration, and soil moisture was higher than the southern areas.

  • XML | PDF | downloads: 253 | views: 381 | pages: 68–77

    Background: Bed bugs as blood-sucking insects have become a public health problem in urban communities through­out the world. The objective of this study was to determine the effects of resident education and self-implementation of Integrated Pest Management (IPM) strategy for eliminating bed bug infestation in infected apartments in Ahvaz City, Iran.
    Methods: This interventional study was conducted in seventy apartments infested with bed bug (Cimex lectularius) in Ahvaz City, southwest Iran, during a 6-month period. The bed bug infestations reported to Health centers were in­spect­ed visually and confirmed by medical entomology experts. Then, the heads of the households were received tech­niques/ tools of the IPM program and trained by medical entomology experts before self-implementation of control methods. Finally, the infected apartments were inspected by the experts at 1, 3, and 6 months after intervention and data were rec­orded in a checklist.
    Results: From the seventy infected apartments, 57%, 28% and 15% were considered as low, moderate, and high level infestation respectively. The bed bug infestation was eliminated from 53 apartments (76%) after one month and it reached to 62 apartments (88%) by the end of third month. Finally, after six months of applying IPM program, bed bugs infestation was eliminated from all infected apartments (100%). Residents expressed their 100% satisfaction with ap­plying the bed bug IPM strategy.
    Conclusion: Training residents to implement the IPM program can reduce pest control costs, the volume of pesticides consumed, and human exposure to chemical pesticides, resulting in increased human and environmental health and safety.

  • XML | PDF | downloads: 329 | views: 426 | pages: 78–87

    Background: The reports of numerous outbreaks of whiteflies from different parts of the world have increased its medical importance. The aim of this study was to determine relationship between environmental changes and climatic factors with the outbreak of the whitefly population in Tehran, the capital of Iran.
    Methods: This study was carried out in urban areas of Tehran, where the increasing population of whiteflies was re­ported frequently during 2018. In order to entrap the whiteflies, 20 yellow sticky cards smeared with white refined grease were installed on the trunks of the trees at twice per month as trapping time intervals. The captured flies were transferred and conserved in cans containing 70% alcohol and were counted accurately under a stereomicroscope. To determine the relationship between air quality index, precipitation, air temperature and air humidity as environmental and climatic factors with the abundance of whiteflies, change point analysis and Generalized Estimating Equations (GEE) was used.
    Results: The most density of white flies per trap was 256.6 and 155.6 in early October and late September respectively. The number moved closer to zero from November to April. The population of whiteflies was inversely correlated with the level of air quality index (p= 0.99) and precipitation (p= 0.95), and it had a direct correlation with the high temper­ature. Also, the population of whiteflies had a direct correlation with the level of air humidity in the first half of the year
    Conclusion: According to these findings, during spring and summer from early May to early October.

  • XML | PDF | downloads: 265 | views: 415 | pages: 88–96

    Background: The emergence and spread of antibiotic resistant bacteria has become a serious problem worldwide. House­flies are potential carriers of pathogenic and resistant bacteria and could be contributing to the global spread of these strains in the environments.We investigated the prevalence and antimicrobial resistant profiles of bacteria isolated from houseflies in Akure.
    Methods: Twenty-five houseflies were captured by a sterile nylon net from the slaughterhouse, garbage dump, human house, hospital, and eatery from 9:00am to 1:00pm when the flies were active and transported immediately to the la­bor­atory in sterile containers for processing. Bacterial loads were enumerated by serial dilution and plating on nutrient agar and selective media. Bacteria species were isolated by conventional isolation technique. Antibiotic susceptibility test was determined by the Kirby-Bauer disc diffusion technique.
    Results: Sixty-seven bacterial species were isolated from 25 samples that were collected. The predominant bacterial species was Escherichia coli (n= 31, 45%), followed by Klebsiella pneumoniae (n= 17, 25%), Staphylococcus aureus (n= 11, 16%) and Pseudomonas aeruginosa (n= 3, 4.3%). The bacterial load of the samples ranged from 9.7×105CFU/mL to 1.65×106CFU/mL. The results revealed that all isolates of Pseudomonas aeruginosa, Salmonella spp, and Proteus mi­rabilis were resistant to streptomycin and cotrimoxazole, augmentin and amoxicillin respectively. None of the S. aureus iso­lates was resistant to cotrimoxazole, chloramphenicol, sparfloxacin, augmentin, and ofloxacin. All isolates were multi-drug resistant.
    Conclusion: House flies that were collected from the slaughterhouse, garbage dump, human house, hospital, and eatery may participate in the dispersal of pathogenic and resistant bacteria in the study environment.

  • XML | PDF | downloads: 271 | views: 386 | pages: 97–105

    Background: Leishmaniasis diseases are known to be one of the most important public health problems in World and Iran. Visceral leishmaniasis is considered to be the most serious form and transmitted by sand flies species. The aim of this study was to investigate the dynamic activities of sandflies in northwestern Iran.
    Methods: This crass-sectional study was conducted from April to December 2018 in Meshkinshahr County, Ardabil Province. Sticky traps have been used to collect sand flies. They are stored in 70% alcohol and finally identified using valid keys. The aspects of the synoptic information were inquired from the Meshkin Shahr weather department and results analyzed for SPSS24.
    Results: Totally 259 sandflies were collected during study period. From collected samples 78.7% were male and 21.3% female. There were 8 different species. Phlebotomus kandelakii was the most prevalent one (30.8%). The average tem­perature, relative humidity, and average wind speed was 13.5 °C, 84%, and 2 meters per hour on the onset of sandflies’ activity, respectively. These values were 18.3 °C, 85% and 1.5 meters per hour at the peak of their activity and 16 °C, 62% and 5 meters per hour at the final stage of their activity. Sand flies had one peak in July which is strongly influ­enced by temperature and humidity conditions. Two species of Ph. kandelakii and Phlebotomus perfilewi transcaucasi­cus, had the highest activity in this endemic area.
    Conclusion: The results of current study will provide a guideline for control of diseases in the country. 

  • XML | PDF | downloads: 290 | views: 386 | pages: 106–115

    Background: Present study was conducted to determine species composition of mosquitoes (larvae, pupae and adults) collected from ten different towns of Lahore from September 2014 to August 2015.
    Methods: Mosquito larvae, pupae and adults (male and female) were collected by using dippers and aspirators from September 2014 to August 2015 in different sites of Lahore comprising of ten towns i.e. Iqbal, Aziz Bhatti, Data Ganj Baksh, Gulberg, Nishtar, Ravi, Samanabad, Shalimar, Wagah, and Lahore Cantonment. Mosquito larvae and adults were identified by standard entomological keys. Diversity, richness and rarity of mosquito fauna were analyzed by the Shannon, Simpson and Margalef indices respectively.
    Results: In this study, a total of 8656 mosquitoes belonging to four genera namely Anopheles, Culex, Aedes and Man­sonia were identified. Among fifteen species collected, Cx. quinquefasciatus was the most abundant species in the city having 25.8% relative abundance. However An. culicifacies s.l. (sensu lato) was reported as the least abundant species with 0.22% relative abundance. The highest diversity of mosquitoes was shown in the month of August (H= 2.25) while the lowest diversity was recorded June (H= 1.43). Extensive sewage water supported the maximum abundance of Cx. quinquifasciatus in urban areas of this city.
    Conclusions: This study has significantly elaborated the monthly varying species composition of mosquito fauna of this city. Hence this research will help us to find out the control strategies of mosquito borne diseases in this region.

  • XML | PDF | downloads: 274 | views: 396 | pages: 116–125

    Background: In domestic and per domestic area,insecticides such as DDT, malathion, fenitrothion, propoxur and, more recently, synthetic pyrethroids such as deltamethrin and lambda-cyhalothrin, have been successfully used to control sand flies in many countries. The present study reports the results of time-mortality bioassay to DDT 4%, lambda-cyhalothrin 0.05%, permethrin 0.75%, cyfluthrin 0.15% and deltamethrin 0.05% in recently colonized Phlebotomus papatasi populations in Iran.
    Methods: The insecticide susceptibility status of P. papatasi laboratory population was assessed during 20162017, following the standard WHO technique for mosquito (WHO, 2013) based on diagnostic dose. Sand flies collected from rural area of Badrood (Matin Abad), Natanz County, Esfahan Province, using aspirator.
    Results: Susceptibility test to DDT and pyrethroids was assessed on 3534 laboratory-reared P. papatasi (1746 females and 1788 males). The LT50 and LT90 values were measured using probit analysis and regression lines. The test results against males of  P. papatasi revealed that LT50 values to DDT 4%, Permethrin 0.75%, Deltamethrin 0.05%, Cyfluthrin 0.15% and Lambdacyhalothrin 0.05% were 439.28, 108.90, 97.75, 5.00 and 57.84 seconds. The figures for females were 641.62, 136.15, 146.44, 8.71 and 72.69 seconds , respectively.
    Conclusion: According to presented results, the reared population of sand flies collected from a hyper-endemic region of Esfahan Province is still susceptible to prethroids and Resistance candidate to DDT 4%.