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1.
J Parasit Dis ; 45(3): 838-844, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34475667

RESUMEN

This study aimed to screen the natural infection rate of Leishmania major in Phlebotomus papatasi and Phlebotomus alexandri in two counties (Mehran and Dehloran) of Ilam province as cutaneous leishmaniasis endemic areas in the west of Iran. Furthermore, the genetic diversity of parasite species that are isolated from vectors, was investigated. Sandflies were collected by sticky traps from May 2018 to October 2018. Afterward, specimens were prepared for species identification by morphological features. DNA was extracted from female sandflies, and minicircle kDNA was used to identify Leishmania isolates through nested-PCR, followed by genetic diversity between Leishmania isolates was investigated by sequence analysis of the amplified minicircle kDNA. Natural infection of the L. major was shown in all positive specimens using nested-PCR. Analysis of data from 14 isolates displayed a high level of genetic diversity in L. major. In the phylogenetic trees, all of the L. major isolates occurred in six clusters. Clusters I, II, III, and VI contained isolated strains from P. papatasi. While clusters IV and V contained isolated strains from P. alexandri. Genetic diversity of L. major isolated from vectors was investigated in western Iran for the first time. According to the results of this study, probably "various clones of L. major populations are distributed in the study area.

2.
Ann Parasitol ; 67(1): 39-44, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34010549

RESUMEN

Leishmaniosis is one of the most important vector borne diseases. Among different forms of the disease, cutaneous leishmaniosis (CL) is the most common. Determining the method of definitive diagnosis for the disease has been the aim of various studies. Therefore this study afforded an opportunity to investigate this subject. To diagnose CL in 150 suspected patients referred to Mehran and Dehloran health centers during June 2018 to November 2019, two polymerase chain reaction (PCR) methods were performed and compared with the in vitro culture and microscopic evaluation of stained slides. The smears were stained with Giemsa for microscopy and cultured in Novy-Nicolle-McNeal (NNN) blood agar for promastigote growth. For semi-nested PCR and PCR-RFLP, the tissue and serosity from the lesions were used for DNA extraction. The semi-nested PCR technique using minicircle kDNA gene showed the highest positivity rates among all diagnostic assays with 114/150 (76%) of the samples and was used as reference standard, followed by the PCR-RFLP test using ITS1 gene with 112/150, (74.7%) positivity rates, microscopy with 101/150 (67.3%) and then culture 72/150 (48%). microscopy and culture methods together improved overall positivity rates to 68.7% (103/150). The all positive samples using molecular technique were identified as Leishmania major. The highest sensitivity (98.3%), specificity (100%), accuracy (98.8%), negative predictive value (94.7%) and κ coefficient (0.96=almost perfect) was observed by comparing PCR-RFLP and semi-nested PCR. kDNA-semi-nested PCR and ITS1-PCR-RFLP presented an interesting alternative to conventional methods for the identification of CL and improved its diagnostic value significantly in suspected patients with negative direct smears.


Asunto(s)
Leishmania major , Leishmaniasis Cutánea , ADN de Cinetoplasto , ADN Protozoario , Humanos , Leishmaniasis Cutánea/diagnóstico , Reacción en Cadena de la Polimerasa , Proyectos de Investigación
3.
J Parasit Dis ; 45(1): 263-272, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33746413

RESUMEN

Cutaneous leishmaniasis is a crucial vector-borne disease caused by various species of Leishmania and is transmitted by several species of sandflies. The present study was conducted to describe sand fly fauna on vectors of leishmaniasis and performing molecular identification of Leishmania isolates from them on the Iran-Iraq border. Entomological surveys were done from May to October 2016-2018 in 2 counties (Mehran and Dehloran) of Ilam province, west of Iran. Sandflies were collected by 40 Sticky Traps at each station. Samples were mounted for species identification using morphological characters of the head and abdominal terminalia. DNA was extracted from Phlebotomus papatasi females, and Leishmania isolates were identified through PCR on minicircle kDNA, followed by sequencing. A total of 5592 sandflies including 2 genera of Phlebotomus and Sergentomyia comprising 8 species of sand flies were detected. Leishmania major infection was detected in 3.33% of 300 tested female sandflies. Phlebotomus papatasi was predominant in outdoor and indoor resting places. Phlebotomus papatasi was determined as dominant vector of Leishmania major infection in Mehran and Dehloran counties, West of Iran. It seems the composition of sandfly species in the study area is almost similar to the other parts of Iran. A detailed description of the epidemiology and ecology of Phlebotomine sand flies needs to be established to accomplish effective vector control programs.

4.
Jundishapur J Microbiol ; 8(10): e23930, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26587213

RESUMEN

BACKGROUND: Blastocystis hominis is a common globally distributed parasite. The prevalence of this parasite has been shown to vary among different countries. Molecular studies have also shown that there is a high level of genetic diversity among Blastocystis spp. isolated from humans and animals. Extensive information on parasitic genotypes will aid in devising more effective strategies for the identification and potential control of these pathogenic parasites. OBJECTIVES: This study aimed to gain information on the prevalence and abundance of Blastocystis subtypes in Iran. MATERIALS AND METHODS: Over a period of 3 months, 1,410 stool samples were collected and examined by microscopy. Samples found to be positive for B. hominis were concentrated and phylogenetic analysis was subsequently performed. A questionnaire was completed by all study participants. RESULTS: Blastocystis hominis was found to have a prevalence of 3.33% in the study population. There was no significant association of Blastocystis infection with age (P = 0.3) or gender (P = 0.57). The Blastocystis subtypes (ST) identified in this study were ST3, ST4, ST5, and ST7 with the most prevalent being ST4 (40.9%). CONCLUSIONS: The prevalence of B. hominis in the study area was lower than that reported for most developed countries, and unlike in other countries in the Middle East, ST4 was the most prevalent subtype.

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