Vol 12 No 2 (2018)

Original Article

  • XML | PDF | downloads: 567 | views: 819 | pages: 101-107

    Background: Natural plant products as larvicides could be considered as desirable alternatives to synthetic chemi­cal insecticides for vector management. This study was undertaken to assess the mosquito larvicide activity of the essential oil from fresh leaves of Platycladus orientalis against two medically important species of mosquito vec­tors.
    Methods:
    Essential oil was extracted by hydrodistillation and analyzed with gas chromatography and mass spec­trometry (GC-MS). Fresh leaves of P. orientalis tree (500g) were collected in June 2014 from Tehran, Iran and was authenticated at the Department of Medical Entomology and Vector Control, School of Public Health, Tehran Uni­versity of Medical Sciences, Tehran, Iran.
    In addition, the larvicidal potential of oil was evaluated against late-3rd or young-4th instar larvae of Anopheles stephensi and Culex pipiens under laboratory condition. The mortality counts were made after 24h and LC50 and LC90 values were calculated.
    Results:
    Forty-six components in leaves of P. orientalis were identified. The major components were α-Pinene (20.17%), 3-Carene (14%) and Cedrol (9.51%). The LC50 values against An. stephensi and Cx. pipiens larvae were 11.67ppm and 18.60ppm after 24h, respectively.
    Conclusion:
    Platycladus orientalis oil could be considered as a natural larvicide for mosquito larval control.

  • XML | PDF | downloads: 359 | views: 534 | pages: 108-118

    Background: Malaria and dengue are the most widespread infectious diseases of tropical countries with an estimated 219 and 50 million cases globally. The aim of the proposed study was to find out discriminating clinical features of falciparum malaria and dengue.
    Method:
    Falciparum malaria was diagnosed by looking at the ring and gametocyte stages by microscopic examina­tion in Giemsa stained slides. Dengue was diagnosed by ELISA for dengue-specific IgM and IgG. Liver enzymes (AST and ALT) and kidney markers (creatinine and urea) were estimated by standard biochemical techniques.
    Result:
    AST and ALT showed similar rise in both, severe malaria and dengue patients but it was much pronounced in dengue haemorrhagic fever where it attained 3–4 folds increase. Creatinine and urea showed higher levels in den­gue compared to malaria. Thrombocytopenia (76.27%), convulsions (18.64%) and hepatic dysfunction (5.08%) were more prominent in dengue than that in malaria where these parameters were 50.89, 7.14 and 2.67%, respectively. Conversely, cases with anaemia, splenomegaly and jaundice were three times more in falciparum malaria. Acute renal failures and neurological sequelae were noticed in slightly higher number of dengue patients.  
    Conclusion:
    Thrombocytopenia and hepatic dysfunction were more common in dengue, while anaemia, splenomeg­aly, jaundice and convulsions were more frequent in falciparum malaria. Neurological sequelae and cases of acute renal failure were almost equal in both the infections.

  • XML | PDF | downloads: 433 | views: 593 | pages: 119-126

    Background: Scrophularia striata is a perennial plant which is native in all parts of Iran, Turkey, and Azerbaijan. In this study, the total phenol content, antioxidant and larvicidal activities of total extract and different fractions of this plant were evaluated.
    Methods:
    The aerial parts of S. striata were collected from Boli village, Illam Province, western Iran in Apr 2013. The total phenol content of total extract and different fractions were evaluated by Folin-Ciocalteu method. Moreover, antioxidant activity was tested by DPPH and FRAPS assays. Larvicidal activity was investigated according to stand­ard method described by WHO.
    Results:
    Ethyl acetate fraction (EF) had the highest content of total phenol (75.9±0.06mg Gallic acid equivalent/g dry extract). Furthermore, among the tested extract, methanol-water fraction (MWF), total methanol extract (TME) and water fraction (WF) showed the highest antioxidant activity in the DPPH assay (IC50= 226.8, 283.66 and 299.4 μg.ml-1, respectively). In FRAP assay MWF and WF and TME had the highest antioxidant activities (664.4±0.002, 565.3±0.003, 519.5±0.003mmol FeII/g dry extract, respectively). Ethyl acetate fraction had maximum larvicidal activity (LC50 49.1ppm) followed by TME (LC50 64.26ppm) and hexane fraction (HF) (LC50 89.69).
    Conclusion:
    Scrophularia striata collected from west of Iran illustrated considerable antioxidant and larvicidal ef­fects and further in vitro and in vivo experimental models for investigation would be required.

  • XML | PDF | downloads: 408 | views: 486 | pages: 127-134

    Background: Rodents are one of the most important hosts for some zoonotic diseases and also act as a reservoir of some ectoparasites and endoparasites. They cause damage to the farms and inflict public health. The aim of this study was to investigate the faunal composition of rodent in North Khorasan Province, Northeast of Iran.
    Methods:
    The sampling was carried out between 2011 to 2013. The specimens were collected using different methods including rodent death and live traps, digging of their burrow, and hand net from 75 different sample sites.
    Results:
    The total number of 396 specimens belonging to 22 species and six families were identified. The results illustrated the high numbers and densities of Meriones persicus (17.68%), Meriones libycus (15.15%), Nesokia indica (7.32%) and Rhombomys opimus (6.82%), as the most important reservoirs for different zoonotic diseases. Moreover, significant number of other rodent species including Mus musculus (15.66%), Apodemus witherbyi (13.89%), A. hyrcanicus (0.25%), Rattus norvegicus (1.01%), Meriones crassus (0.25%), Gerbillus nanus (0.51%), Microtus paradoxus (2.27%), M. transcaspicus (0.76%), Ellobius fuscocapillus (0.25%), Cricetulus migratorius (4.29%), Calomyscus elburzensis (4.29%), C. mystax (1.26%), Spermophilus fulvus (0.25%), Dryomys nitedula (3.54%), Allactaga elater (3.54%), Jaculus blanfordi (0.25%), Meriones zarudnyi (0.25%), M. meridianus (0.51%), and Hystrix indica as hosts for parasites and zoonotic diseases were identified.
    Conclusion:
    The high biodiversity including at least 22 species and six families of rodents were found in North Khorasan Province, some of them were medically important species.

  • XML | PDF | downloads: 361 | views: 593 | pages: 135-140

    Background: Development of resistance against the frontline anti-malarial drugs has created an alarming situation, which requires intensive drug discovery to develop new, more effective, affordable and accessible anti-malarial agents. The aim of this study was to assess antiplasmodial activity of the different fractions of root extract of Glycyr­rhiza glabra.
    Methods
    : Roots of G. glabra were collected from Tarom district of Zanjan Province in 2016 and then dried root ma­terial was chopped and consecutively extracted by the percolation method using solvents of different polarity. Result­ing extracts were assessed for in vitro and in vivo anti-malarial and cell cytotoxicity activities.
    Results
    : Among the three different solvent fractions studied, water-methanol and ethyl acetate fractions showed promising in vitro antiplasmodial activity against CQ-sensitive Plasmodium falciparum 3D7 strain (IC50= 9.95 and 13µg/ml, respectively). Further, the selectivity indices (HeLa cells versus P. falciparum) for the promising water-methanol fraction showed selectivity for P. falciparum and potential safer therapy for human. Interestingly, water-methanol and ethyl acetate fractions showed a significant suppression of parasite growth (72.2% and 65%, respec­tively) in comparison with control group in mice infected with P. berghei (P< 0.05).
    Conclusion
    : The promising antiplasmodial activity of the aqueous fraction of G. glabra obtained in our study war­rant bioassay-guided fractionation of this fraction to identify active principles responsible for antiplasmodial activity.

  • XML | PDF | downloads: 583 | views: 664 | pages: 141-151

    Background: Domiciliary cockroaches are obnoxious pests of significant medical importance. We investigated the prevalence of human intestinal parasites in cockroaches and its attendant public health importance.
    Methods:
    Overall, 749 cockroaches (Periplaneta americana, 509, Blattella germanica, 240) caught by trapping from 120 households comprising 3 different housing types in Somolu, Lagos metropolis, southwest Nigeria, in 2015 were screened for human intestinal parasites using standard parasitological techniques.
    Results:
    The prevalence of human intestinal parasites in cockroaches was 96.4%. There was no statistically signifi­cant difference (P> 0.05) in parasite prevalences between P. americana (95.7%) and B. germanica (97.9%). Parasite species identified and their prevalence were as follows: Entamoeba histolytica/dispar (44.1%), E. coli (37.8%), Gi­ardia lamblia (18.7%), Cryptosporidium sp. (13.8%), Ascaris lumbricoides (61.3%), Trichuris trichiura (55.8%), hookworms (11.6%), Strongyloides stercoralis (11.7%), Taenia/Echinococcus spp. (10.5%), Enterobius vermicularis (17.2%) and Hymenolepis nana (11.6%). Parasite prevalence and burdens varied with housing type; the prevalence was significantly higher statistically (P< 0.05) in cockroaches from low-cost bungalow, LCB (100%) and low-cost, 2-storey, LC2-S (100%) houses than in medium-cost flats, MCF (81.3%). Parasite burdens were also significantly higher statistically (P< 0.05) in cockroaches from LCB or LC2-S than in cockroaches from MCF. Parasite preva­lences between cockroach gut and body surfaces were not statistically significant (P> 0.05) but mean parasite bur­dens in gut were significantly higher statistically (P< 0.05) than on body surfaces.
    Conclusion:
    Cockroaches types carry transmissive stages of human intestinal parasites and may act as reservoirs and potential mechanical vectors for disease transmission.

  • XML | PDF | downloads: 327 | views: 480 | pages: 152-161

    Background: Tick-borne diseases are caused by several pathogens whose transmission could be associated to the life conditions of communities settled in endemic areas. We aimed to determine the knowledge, attitudes, and prac­tices related to the exposition and prevention of tick-borne diseases among people living in a typical Mayan commu­nity of Yucatan, Mexico between Dec 2012 and May 2013.
    Methods:
    A directed survey was applied to 212 (100%) householders (women and men) from Teabo, Yucatan, Mex­ico. Answers and field notes were recorded and analyzed with central statistics.
    Results:
    People have been bitten at least once in the community, but the majority of them consider those bites innoc­uous. In addition, people do not consider prevention measures, and only a few mentioned the use of some chemicals on their backyards.
    Conclusion
    : This study found little awareness among the participants regarding the importance and the transmission of these diseases even though they possess a vast knowledge regarding ticks. Therefore, educational strategies and prevention programs that include these habits for its modification are required to minimize the exposition to the vec­tors.

  • XML | PDF | downloads: 426 | views: 632 | pages: 162-171

    Background: Leishmaniasis is a major medical health problem and distributes in nearly half of 31 provinces of Iran. We aimed to identify cutaneous and visceral Leishmania spp. isolated from infected humans and domestic dogs in various regions of Iran, 2010‒2013.
    Methods:
    DNA was extracted from 108 lesion exudate samples of suspected patients to cutaneous leishmaniasis and nine liver and spleen aspirates of infected dogs cultured in RPMI-1640 and amplified using partial sequence of ITS1 gene. The PCR amplicons were digested using HaeIII endonuclease enzyme and used in restriction fragment length polymorphism (RFLP) assay. Then, 48 amplicons representing various hosts were sequenced and compared to se­quences from GenBank databases using BLAST.
    Results:
    PCR-RFLP analysis showed that 60 and 48 CL patients were infected by Leishmania tropica and L. major, respectively. From nine canine visceral leishmaniasis (CVL) isolates, eight isolates were identified as L. infantum and one as L. tropica. The greatest similarity of 95.7% in ITS1 region was seen between L. infantum and L. major. Furthermore, the lowest similarity with 65.7% was seen between L. tropica and L. major. Intra-species comparison of ITS1 region in L. infantum, L. major and L. tropica isolates were showed 100%, 98.2% and 72.4 % similarities, respectively.
    Conclusion:
    PCR-RFLP based on ITS1 region is an appropriate method to distinguish three Leishmania spp. of L. major, L. tropica, and L. infantum. In intra-species comparison of ITS1 region, genotypic variations showed that L. tropica isolates were more heterogeneous than L. major and L. infantum isolates.

  • XML | PDF | downloads: 690 | views: 607 | pages: 172-179

    Background: Cockroaches consists of 4000 species, of which 40 species are serious domestic pests. They have involved the mechanical transmission of various pathogenic viruses, bacteria, and protozoans to humans. This study aimed to determine different control methods of P. americana in sewage system of Esfahan City, central Iran using different insecticides recommended by WHO. Methods: Totally, 164 manholes with at least more than three cockroaches were selected until 2017 for this study. The species of cockroaches were identified; the adults and nymphs were counted and recorded. Each sewer shaft was assigned to one treatment method in an ascending order of number of cockroaches counted, coding the treatment method with paint on the lower part of the wall near the manhole cover. The manhole shafts were then inspected at 1 and 5 months’ post-treatment. Data analyzed by statistical methods.
    Results
    : Almost all of the products (Excluding boric acid with bait formulation) resulted in appropriate control with­in one month of application. The appropriate products for chemical control of cockroaches were the chlorpyrifos 5% Emulsifiable Concentrate (EC), diazinon 5% (EC), diazinon 0.05% (EC) and cypermethrin 5% Fog. These pesticides achieved an optimal reduction of population providing more than 90% control of cockroaches for five consecutive months.
    Conclusion
    : The emulsifiable concentrates and fog formulations in the control were more successful compared to other methods and this was penetration deep into the hiding places of cockroaches.

  • XML | PDF | downloads: 410 | views: 448 | pages: 180-195

    Background: The aim of this study was to explore the experiences of patients who suffer from acute cutaneous leishmaniasis in Iran, focusing on quality of life.
    Methods:
    The study was conducted at two different sites in Iran in 2010–2011. Individual in-depth interviews were conducted with six men and six women parasitologically confirmed acute cutaneous leishmaniasis. Interviews were recorded, transcribed verbatim, and translated into English. Qualitative content analysis was used for data analysis.
    Results:
    The participants, aged 23 to 63yr, had mild to severe disease. Based on the analysis four main themes were developed. "Fearing an agonizing disease" reflects patients' experiences of disease development resulting in sadness and depression, "struggling to cope" and "taking on the blame" both illustrate how patients experience living with the disease, which included both felt and enacted stigma as major social concerns. "Longing for being seen and heard" refers to patients' experiences with healthcare as well as their expectations and demands from communities and healthcare to be involved in closing the knowledge and awareness gap.
    Conclusion:
    Mental and social dimensions of cutaneous leishmaniasis were complex and adversely affected patients' lives by causing psychological burden and limiting their social interactions. Health authorities have to plan programs to increase the disease awareness to prevent the existing stigma to improve patients' social condition and medical care.