Vol 4 No 2 (2010)

Articles

  • XML | PDF | downloads: 339 | views: 408 | pages: 1-10

    Background: Haematophagous females of some phlebotomine sandflies are the only natural vectors of Leishmania species, the causative agents of leishmaniasis in many parts of the tropics and subtropics, including Iran.  We report the presence of Phlebotomus (Larroussius) major and Phlebotomus (Adlerius) halepensis in Tonekabon (Ma­zanderan Province) and Phlebotomus (Larroussius) tobbi in Pakdasht (Tehran Province). It is the first report of these species, known as potential vectors of zoonotic visceral leishmaniasis in Iran, are identified in these areas.
    Methods: In 2006-2007 individual wild-caught sandflies were characterized by both morphological features and sequence analysis of their mitochondrial genes (Cytochrome b).  The analyses were based on a fragment of  494 bp at the 3´ end of the Cyt b gene (Cyt b 3´ fragment) and a fragment of  382 bp CB3 at the 5´ end of the Cyt b gene (Cyt b 5´ fragment). We also analysed the Cyt b Long fragment, which is located on the last 717 bp of the Cyt b gene, followed by 20 bp of intergenic spacer and the transfer RNA ser(TCN) gene.
    Results: Twenty-seven P. halepensis and four P. major from Dohezar, Tonekabon, Mazanderan province and 8 P. tobbi from Packdasht, Tehran Province were identified by morphological and molecular characters. Cyt b 5´ and Cyt b 3´ fragment sequences were obtained from 15 and 9 flies, respectively. Cyt b long fragment sequences were ob­tained from 8 out of 27 P. halepensis.
    Conclusion: Parsimony analyses (using heuristic searches) of the DNA sequences of Cyt b always showed mono­phyletic clades of subgenera and each species did form a monophyletic group.

  • XML | PDF | downloads: 310 | views: 636 | pages: 11-18

    Background: Since organophosphorus pesticides are widely used for industry and insect control in agricultural crops, their fate in the environment is very important. Pesticide contamination of surface water has been recog­nized as a major contaminant in world because of their potential toxicity towards human and animals. The objec­tive of this research was to investigate the influence of various parameters including the influence of time, power, and initial concentration on degradation of diazinon pesticide.
    Methods: The sonochemical degradation of diazinon was investigated using acoustical processor reactor. Acous­tical processor reactor with 130 kHz was used to study the degradation of pesticide solution. Samples were ana­lyzed using HPLC at different time intervals. Effectiveness of APR at different times (20, 40, 60, 80, 100, and 120 min), concentrations (2, 4 and 8 mg/L) and powers (300W, 400W, 500W) were compared.
    Results: The degradation of the diazinon at lower concentrations was greater in comparison to higher concentra­tions. There was also direct correlation between power and diazinon degradation. In addition, when the power increased, the ability to degraded diazinon increased.
    Conclusion: The sonodegradation of diazinon pesticide at different concentrations and powers was successfully provided. It has been shown that APR can be used to reduce the concentration of dissolved pesticide using high frequency.

  • XML | PDF | downloads: 368 | views: 466 | pages: 19-25

    Background: A molecular survey was conducted to investigatethe presence of pathogenic Borrelia persica species caus­ing the tick borne relapsing fever (TBRF) in Takistan district Qazvin Province, western Iran.
    Methods: A number of 1021 soft ticks were collected from 31 villages including previously reported infected and none-infected TBRF cases and individually examined for the presenceof B. persica DNA by conventional PCR target­ing the 16SrRNA.
    Results: A total of 1021 soft ticks of three species of Ornithodouros tholozani (120: 11.75%), O. lahorensis (461: 45.15%) and Argas persicus (440: 43.1%) were collected and tested against Borrelia infection. Soft ticks were more preva­lent (67%) in infected areas than none infected areas. The rate O. tholozani in infected areas was much greater (29 times) than none infected areas. Ninety seven percent of soft ticks in none infected areas were of O. tholozani. Six­teen (16.7%) ticks of tested (n=95) O. tholozani were infected with B. persica. Three (1.3%) out of 205 soft ticks of O. lahorensis were positive for Borrelia sp., and no infection was observed in A. persicus. TaqI RFLP analysisand se­quence analysis of the positive PCR products showed the presence of B. persica. The RFLP analysis showed that the positive ticks of O. lahorensis were infected with unknown Borrelia species.
    Conclusion: This study showed that although there were no TBRF cases in Takisan, but still infected O. tholozani, the known vector of TBRF, presented in the region. Control measures needs to be fulfilled in Thakisan. 

  • XML | PDF | downloads: 399 | views: 735 | pages: 26-34

                                                                                           

    Background: Regarding to the significant of the possibility of the malaria epidemic and nuisance of mosquitoes dur­ing the active season, the fauna and some ecological activities of mosquitoes in related to tree holes were investi­gated from April to December 2009 in Neka county of Mazandaran Province, northern Iran.
    Methods: Larval collection was carried out from natural, artificial breeding places, and tree holes inside the forest in Neka County, Mazandaran Province in 2009. In addition, human bait net trap collection was conducted using suction tube several times during this investigation.
    Results: Four genera and five species were found in tree holes. Anopheles plumbeus, Culiseta annulata, Culex  pipiens, and Ochlerotatus geniculatus were collected by larval collection whereas, Ochlerotatus pulcritarsis was found by adult collection. Overall Cx. pipiens 44.6%, Oc. geniculatus 32.6%, An. plumbeus 22.5%, and Cs. annulata 0.3% were collected by larval collection. During the bait net collection five specie were identified including: Oc. genicula­tus 55.87%, Oc. echinus 1.33%, Oc. pulchritarsis 8.8 %, Cx. pipiens 33.8%, and An. plumbeus 0.2%. Cs.  annu­lata larvae was detected for the first time with a low abundance in tree cavity.
    Conclusion: Tree holes were found the main habitat for the species of Oc. geniculatus. The species of Cs.  annulata was found in tree holes

  • XML | PDF | downloads: 412 | views: 4766 | pages: 35-41

    Background: Use of bed-net continues to offer potential strategy for malaria prevention in endemic areas. Local communi­ties are indispensable during design and implementation stages.
    Methods: A cross-sectional study of 192 randomly selected inhabitants was carried out in malarious zone, Siahoo dire­strict, Hormozgan Province, southern Iran. In addition, we monitored human landing periodicity of main malaria vec­tors and as well as self-protection of inhabitant in the study area for a period of one transmission season between April to October 2006.
    Results: The biting activities were seen throughout the whole night for three malaria vectors, Anopheles fluviatilis, An. stephensi and An. Dthali, and  An. fluviatilis exhibiting bimodal peaks, the first at midnight (0:00-1:00) and the other before dawn (5:00−6:00 am) but the maximum biting activity of An. stephensi was occurred at second quarter of night (11:00-12:00 pm). The majority of interviewers (83.3%) knew that malaria was transmitted by mosquitoes and 70.3% of them stated that bed-net is the best control measures. Most subjects (62%) did not have a mosquito net.
    Conclusion: Study subjects were aware of an association between mosquito bite and malaria transmission. Health work­ers at different levels of the health care delivery system should disseminate relevant information about self-protection to help community members to be involved more in malaria control.

  • XML | PDF | downloads: 311 | views: 498 | pages: 42-49

    Background: Culex pipiens complex shows variations in morphological and biological characters including differ­ent biological forms and has medical and veterinary importance. Because of having morphological variations, some­times it is not easy to separate this species from Cx. quinquefasciatusand Cx. torrentium.The aim of this study was to  identify the  Culex pipiens complex species in order to use in control programs in the future.
    Methods: This study was carried out in two randomly selected rural villages in Yazd County, eastern Iran using dip­ping technique from April to October 2009. The data were analyzed using SPSS software version 16.
    Results: Average of siphon index in fourth-instrar larvae was 3.86±0.03, the minimum and maximum were calculated 2.43 and 5.14, respectively. Siphon/Saddle index was measured as average, minimum and maximum 3.2±0.2, 2.78, and 4.42 respectively. In our study, only 4 specimens had single seta 1 on segments III and VI (2.5%) and the remaining beard double seta (97.5%). The maximum 3-6 branches seta 1a-S and 1b-S (95%) were observed on siphon.
    Conclusion: More populations of Culex pipiens from different areas of Iran need to be studied to gain complete informa­tion about the taxonomy and ecology of the species in the country.

  • XML | PDF | downloads: 522 | views: 426 | pages: 50-55

    Background: In this study, we determine the vector competence of Musca domestica with reference to the transmis­sion of susceptible and resistance bacterial strains in hospitals and slaughter house in Sanandaj City, west Iran.
    Methods: Totally 908 houseflies were collected to isolate bacteria from their external body based on standard proce­dures.Antibiotic susceptibility testing was performed by Kirby-Bauer disc diffusion method on Mueller Hinton agar based on recommendations of CLSI (formerly the National Committee for Clinical Laboratory Standards).
    Results: From collected houseflies, 366 bacteria species were isolated. The most common isolated bacterium at hos­pitals was Klebsiella pneumoniae 43.3% (n= 90) followed by Pseudomonas aeruginosa 37% (n= 77), while that of slaughterhouse was Proteus mirabilis. 29.1% (n= 46) followed by Citrobacter freundii 28.4% (n= 45). Among all the isolates from hospitals, cephalexin, chloramphenicol, ampicillin, and tetracycline, resistance rates were above 32.5% and gentamicin expressed the highest susceptibility among all the isolates from hospitals. It is worth to note that K. pneumoniae showed 61% and 44.5% resistance to cephalexin and chloramphenicol respectively. Similarly, all iso­lates from slaughterhouse were more than 28% and 30% resistant to cephalexin and chloramphenicol respectively. Surprisingly, among all the isolates, Citrobacter freundii were highly resistant to gentamicin.
    Conclusion: Houseflies collected from hospitals and slaughterhouse may be involved in the spread of drug resistant bacteria and may increase the potential of human exposure to drug resistant bacteria.

  • XML | PDF | downloads: 377 | views: 426 | pages: 56-60

    Background: Ticks are hematophagous arthropod belonging to the Class of Arachnids. Ticks are also one of the major vectors of pathogens to animal and human. This study was conducted to determine tick infestation rate of sheep in Abdanan during 2007–2008.
    Methods: Sampling was performed seasonally in 19 villages during spring 2007 until winter 2008. A total of 1095 sheep were selected and tested for tick infestation.  After collection, all ticks were transported to laboratory of Medi­cal Entomology and were identified with appropriate identification keys.
    Results: Totally, 864 hard ticks were collected. The ticks were classified into two genera and 5 species including: Hyalomma marginatum (44.67%), Hy. anatolicum (43.17%), Hy.asiaticum (6.37%), Hy. dromedarii (5.55%), Hea­maphysalis sulcata (0.24%). The highest seasonal activity was observed in spring (36.46 %) and the lowest seasonal was in winter (11.57%). The rate of tick frequency in mountainous region was 48.15% and it was 51.85% in plateau regions. In this study, tick infestation of sheep was 11.41%.
    Conclusion: Hy.marginatum has the more frequent density in the study area.

  • XML | PDF | downloads: 326 | views: 459 | pages: 61-67

    Background: The aims of this study was to analysis the current situation of malaria and to find the distribution of anopheline mosquitoes, as probable vectors of the disease, in Qom Province, central Iran.
    Methods: This study was carried out in two parts. First stage was data collection about malaria cases using recorded documents of patients in the Province health center, during 2001–2008. The second stage was entomological survey conducted by mosquito larval collection method in 4 villages with different geographical positions in 2008. Data were analyzed using Excel software.
    Results: Of 4456 blood slides, 10.9% out were positive. Most of cases were imported from other countries (90.4%), mainly from Afghanistan (56.5%) and Pakistan (16.3%). Slide positive rate showed a maximum of 16.9% and a minimum of 2.9% in 2008 and 2007, respectively. Plasmodium vivax was causative agent of 93.75% of cases, fol­lowed by P. falciparum (6.25%). More than 15 years old age group contained the most malaria reported cases (66.7%). Two Anopheles species, An. superpictus and An. claviger were collected and identified. This is the first report of Anopheles claviger in Qom Province.
    Conclusion: Malaria is in the control stage in Qom Province. The rate of local transmission is very low (only 1 case), shows Anopheles superpictus, as the main malaria vector of central part of Iran, can play its role in malaria transmission in the area.

  • XML | PDF | downloads: 390 | views: 472 | pages: 68-71

    Otodectes cynotis, ear mite or ear canker mite, is the most common cause of otitis externa in cats (approximately 50%) and to a lesser extent in dogs, foxes and ferrets. The mite is living on the epidermal surface of auditory canal without burrowing into the tissueand feeding on tissue fluids and debris. In most of the cases they induce hypersensitiv­ity reactions in the host. Four puppies; Siberian husky, Cocker spaniel, Terrier and mixed Pekignese with different genders and ages were referred to the small animal hospital, Veterinary Faculty of Tehran University, Tehran, Iran for routine clinical examination just after they were imported from Thailand in a timeframe between June to August 2008.
    Clinical examinations showed an excessive dark brown discharge in both ears. No signs of other clinical situations were observed. White moving mites were seen during otoscopy examination. The specimen of ear discharge was sent to parasitology laboratory for precise identification of genus and species. Mites were identified as Otodectes cynotis and the presence of concurrent yeast and bacterial infection was showed by laboratory examinations. Topical Ami­traz solution in combination with otic antibacterial and antifungal agents were administered as the treatment. Since, all the reported cases were imported from Thailand, careful clinical examination and quarantine strategies are highly recommended at the borders.