Seroprevalence Survey of Visceral Leishmaniasis among Children up to 12 Years old and Domestic Dogs in Rural Areas of Dehloran District, Ilam Province of West Part of Iran, 2014

Background: Visceral leishmaniasis (VL), caused by Leishmania infantum (L. infantum), is a life-threatening vector-borne parasitic disease is distributed in some parts of the world. The disease is endemic in some parts of Iran. This study was aimed to determine the seroprevalence of VL among children and domestic dogs (as a reservoir of the parasite) in Dehloran, west of Iran.Materials and Methods: This cross-sectional study was carried out in Dehloran County. The blood samples of 872 children up to 12 years old and 52 dogs were collected from 10 villages of Dehloran using randomly-clustered sampling method. Sera were separated from all peripheral blood samples and tested by direct agglutination test (DAT). Anti-Leishmania infantum antibodies at titers of ≥1:800 and ≥1:80 were considered as Leishmania infantum infection in human and dog, respectively.Results: In general, among 872 human samples, 1.03% of samples had anti-Leishmania antibody with 1:1600 titers and 1.26% had 1:800 titers. In addition, from 52 dog samples, 21.15% of dogs had a titer of ≥1:320 and 25% had 1:80 and 1:160 titers.Conclusion: Our findings indicate that the seropositive dogs in the studied areas are considerable and L. infantum may be circulated between human and domestic dog in the studied area. Further study of isolation and molecular identification of Leishmania spp. is recommended

Human Visceral Leishmaniasis: a Serological Survey in Rural Areas of Dashti District of Bushehr Province, Southern Iran

Background: Visceral leishmaniasis (VL) or kala-azar is a parasitic disease caused by the species of Leishmania donovani complex. Mediterranean type of the disease is endemic in some parts of Iran and more than 95% of cases were reported in children up to 12 years of age. This study was performed to determine the seroprevalence of VL in the rural areas of the Dashti district from Bushehr province.Materials and Methods: In this cross-sectional study, a randomized cluster sampling method was used for the collection of blood samples from children up to 12 years old from rural areas of Dashti district. Before sampling; a questionnaire was filled out for each case. All the collected blood samples were examined after the serum separating by Direct Agglutination Test (DAT) for detection of anti-Leishmania infantum antibodies. The cutoff titers of ≥1: 3200 with specific clinical features were supposed to be considered as VL.Results: Altogether, 24 out of 1221 (1.96%) blood samples showed titers between 1:800 and 1:1600 which considered as suspicious cases. None of the suspicious cases had a history of kala-azar. None of 1221 collected blood samples showed anti Leishmania infantum (L. infantum) at titer ≥1:3200.Conclusion: This study confirms the circulation of L. infantum in Dashti district and highlights the sporadic pattern of VL in the studied areas which necessitates the surveillance system to be monitored by health authorities

Epidemiological aspects of canine visceral leishmaniosis in the Islamic Republic of Iran

An epidemiological study to examine the sero-prevalence of zoonotic visceral leishmaniosis (ZVL) among domestic and wild canines in endemic foci of Iran was carried out during 1999-2003 to assess the distribution of the disease and the possible association between infection in dogs, wild canines and people. Anti-leishmanial antibodies were detected by the direct agglutination test (DAT). Parasitological study was performed for all captured wild canines and were detected in some of the seropositive dogs with specific clinical signs (n = 107). Serum samples (n = 1568) were collected from domestic dogs in villages that are known endemic foci of human visceral leishmaniosis (HVL). Wild canine sera were collected from jackals (Canis aureus, n = 10), foxes (Vulpes vulpes, n = 10) and wolves (Canis lupus, n = 10). Of the 1568 serum sampled collected from domestic dogs, 222 (14.2%) were positive by DAT (1:320 and above). No statistically significant difference was found between male (15.2%) and female (11.8%) sero-prevalence (P = 0.083). Dogs of 8 years and above showed the highest sero-prevalence (40.6%). Only 23.9% of the seropositive domestic dogs had clinical signs. Parasitology and serology tests that were performed in 30 wild canines showed 10% these animals were infected by Leishmania infantum. Ten out of 11 Leishmania spp. isolated from the dogs and wild canines were identified as L infantum and one other as L. tropica by molecular and biochemical techniques. For the first time in Iran, L. infantum and L. tropica were isolated from viscera of both a wolf and a domestic dog. (c) 2005 Elsevier B.V. All rights reserved

Western Blot Analysis of Leishmania infantum Antigens in Se-ra of Patients with Visceral Leishmaniasis

Background: Visceral leishmaniasis (VL) is endemic in the northwest and south of Iran. Untreated cases of VL could cause death. The aim of the present study was to evaluate the diagnostic performance of western blotting to detect a specific immunodominant proteins pattern for Leishmania infantum infection using human sera infected with VL. Methods: We studied a panel of 122 cryopreserved human serum samples from the leishmaniasis Research Laboratory, Tehran University of Medical Sciences, Tehran, Iran from 2010 to 2017. Serum samples were collected from visceral (Group I, n: 43) and cutaneous leishmaniasis (CL) (Group II, n: 8) patients, healthy individuals from endemic (Group III, n: 13) and non-endemic (Group IV, n: 16) areas for VL, and patients with other infectious diseases (Group V, n: 42). Total antigens were prepared from the Iranian strain of L. infantum promastigote form. Results: In western blotting method, 34 protein bands of 14 to 163 kDa were recognized using the sera of VL pa­tients. The polypeptide fractions with the highest frequency including 29, 51, and 62 kDa fractions were detected using 81.4%, 79%, and 81.4% of the sera, respectively. These bands were not detected using the sera of the negative control. Moreover, 19-23, 27, 31-35, 143-163, and 109 kDa fractions were detected specifically using the sera of the patients with VL. Conclusion: This technique could be a primary step for further exploration of VL immunodominant antigens for cloning (or any technique) further investigations for future planning

Molecular Identification of Cutaneous Leishmaniasis Species in the Northcentral Iranian Province of Alborz: Is There a New Focus on Cutaneous Leishmaniasis in the Province?

Background: Cutaneous leishmaniasis (CL) is an endemic infection in the Middle East, including Iran that is also spreading to new foci. We aimed to determine the leishmaniasis species causing CL in Alborz province. Methods: Overall, out of 55-suspected CL patients referred to health centers in Alborz Province, north central Iran in 2019, 40 patients had positive smear for CL based on optical microscopy. The internal transcribed spacer 1 (ITS1) of nuclear ribosomal DNA (rDNA) was amplified by PCR. Leishmania species were identified by PCR–restriction fragment length polymorphism (PCR-RFLP) using BshF I (Hae III) enzyme. Results: Out of the 40 positive patients with CL, 34 cases (85%) had been caused by Leishmania (L) major and six (15%) by L. tropica. Fifteen patients had no history of traveling to the disease endemic areas, of which nine were Iranians. Skin lesions and scars caused by CL were mostly observed on the hands and face. Moreover, more than two skin lesions were observed in 22 cases (55%), all of which were infected with L. major. A single skin ulcer was seen in 18 (45%) of the CL patients. Conclusion:  Climate change, reduced rainfall, and demographic changes such as migration into Alborz Province and the increasing marginalization of the population and their entry to settle in new areas might have caused natural transmission of both L. tropica and L. major in this province

The Association of Human Leucocyte Antigen (HLA) Class I and II Genes with Cutaneous and Visceral Leishmaniasis in Iranian Patients: A Preliminary Case-Control Study

Background: Leishmaniasis is currently considered a re-emerging or emerging infection based on the geographic region. The outcome of leishmaniasis vastly depends on Leishmania-host interaction. This preliminary study aimed to show the association of human leukocyte antigen (HLA) class I and II genes with healed and non-healed cutaneous leishmaniasis (CL), and symptomatic and asymptomatic visceral leishmaniasis (VL) compared with control groups in Iran. Methods: Ninety-five people, including 31 patients versus 64 individuals in the control group, were enrolled. Among them, 20 patients had confirmed CL based on amastigote observation, 10 had improved CL and 10 non-healed CL. Eleven patients were suffering from confirmed VL based on direct agglutination test (Five asymptomatic and six symptomatic VL cases). Besides, they were residents in an endemic area of VL in the northwest of Iran. To select a control group, it was ensured that they had no history of leishmaniasis. Peripheral blood samples were collected from each patient. After DNA extraction, HLA typing was conducted using polymerase chain reaction - sequence-specific priming (PCR-SSP). Subsequently, data were statistically analyzed by SPSS.   Results: There was a statistical relationship between the presence of HLA-A26 and CL, healed CL and the existence of the B38 allele, C1 allele and symptomatic VL, as well as B1.4 allele and asymptomatic VL (P˂0.05). Conclusion: This primary finding indicates that several HLA genes have a potential role in the susceptibility of Iranian people to CL and VL

Potent antileishmanial activity of chitosan against Iranian strain of Leishmania major (MRHO/IR/75/ER): In vitro and in vivo assay

Background & objectives: Leishmaniasis is one of the major neglected zoonotic parasitic diseases whose treatment and control is very complex. Pentavalent antimonials remain the primary drugs against different forms of leishmaniasis, however, resistance to antimony and its toxic effects has necessitated the development of alternative medications such as use of medicinal plants and natural compounds. The aim of the current study was to assess the in vitro and in vivo activities of chitosan as a natural resource against Leishmania major. Methods: Low molecular weight chitosan, with 95% degree of deacetylation was melted in normal saline to a final concentration of 50, 100, 200 and 400 μg/ml. Then, the promastigotes of L. major (Iranian strain) were added to the wells of 96-well plate and 20 μl of each concentration was added to the RPMI 1640 medium. Live and dead promastigotes were counted after adding 0.1% eosin stain. The efficacy of the chitosan was also examined in BALB/c mice infected with Iranian strain of L. major. All in vitro experiments were performed in triplicate and the results of in vitro and in vivo tests were compared to the acetic acid and NaOH as negative control and glucantime as positive control. Results: The low molecular weight chitosan was completely effective at concentrations of 100, 200 and 400 μg/ml on promastigotes of L. major after 180 min of application. Moreover, in the in vivo study, the mean size of dermal lesions significantly decreased in the groups treated with the chitosan compared to the control group. Interpretation & conclusion: According to the results of the study, it can be concluded that chitosan is a potent active compound against L. major and could be evaluated as a new antileishmanial drug in the future

Seroepidemiological Survey of Human Visceral Leishmaniasis in Ilam Province, West of Iran In 2013

  Background: Visceral leishmaniasis (VL) as one of the most important human parasitic disease is endemic in some parts of Iran. Several cases of VL have been reported recently in the Ilam Province. The current study aimed to assess the pre-sent status of human VL in the region. Methods: A random cluster sampling method was used to collect 456 serums samples from the children up to 12 years of age and 10% of adults living in urban and rural areas of the province. All the collected serum samples were tested by di-rect agglutination test (DAT) to detect anti- Leishmania infantum antibodies. Results: Of the examined 456 serum samples with direct agglutination test (DAT), only 21 (0.43%) sera showed anti- Leishmania antibodies at titers 1:400 and higher. Distribution of anti- Leishmania antibodies titers were: 1:400(n=4), 1:800(n=11), 1:1600(n=3), 1:3200(n=1), and 1:6400(n=1). Individuals with titers ≥1:3200 showed clinical signs and symptoms such as fever and splenomegaly. The highest and lowest seropositivity were observed in the age groups of 5–9 and >15 years old, respectively. There were no significant difference between the rate of seroposi-tivity in males and females. Conclusion:VL with a low prevalence circulates in some parts of Ilam province, particularly in the southern parts. Complementary studies should be needed to find animal reservoir hosts and vectors. Furthermore

Modification on Direct Agglutination Antigen Preparation for Simplified Sero-Diagnosis of Human and Canine Visceral Leishmaniasis

Background: Visceral leishmaniasis is systematic serous parasitic disease with pub­lic health importance. Zoonotic form of visceral leishmaniasis is wide spread in Mediterranean basin and South America regions. Direct agglutination test (DAT) is an accurate, reliable and non-expensive serological test for the diagnosis of visceral leishmaniasis in human and canines but the antigen preparation involves some limita­tions. This study aimed to compare the conventional production of DAT anti­gen with our modified DAT antigen and then assessed on human and dog pooled sera. Methods: Conventional DAT antigen has been prepared at the School of Public Health, Tehran University of Medical Sciences and some modifications were car­ried out on it, which named as modified DAT antigen. Three positive and one nega­tive human and dog pooled serum were separately used for the comparison of modified DAT with conventional DAT antigen batches with one-month interval for a period of 9 months. Results: A good concordance was observed between modified DAT compared to conventional DAT antigens for the detection of visceral leishmaniasis on human (100%) and dog (94.4%) pooled sera, respectively. Conclusion: Since the modified DAT antigen could be reduced the preparation time from 3 days to several hours and a good degree of agreement was found between modified DAT and convention DAT antigen batches, it can be used as a simple and easy tool for screening and serodiagnosis of human and canine L. infan­tum infection