Endemic Area Of Cutaneous Leishmaniasis Research Articles

Ecology and Infection Status of Sand Flies in Rural and Urban Cutaneous Leishmaniasis Endemic Areas in Northwest Ethiopia.

Cutaneous leishmaniasis (CL) caused by Leishmania aethiopica is transmitted by Phlebotomus longipes in northern Ethiopia. No studies have been conducted to investigate the transmission dynamics of CL, despite its high endemicity in both rural and urban settings. Evidence on the ecology and behavior of the vector from this area are required to develop integrated disease control strategies. Sand flies were collected in the dry and wet seasons in 2021 in CL-endemic rural Gindmeteaye and urban Addis-Alem in northwest Ethiopia. Trapping was performed with sticky and Centers for Disease Control and Prevention (CDC) light traps in three habitats, including inside patients' houses, peridomestic areasand in caves/rocky areas. Sand flies were morphologically identified to species level. Female Phlebotomus species were categorized according to blood feeding status and tested by spliced-leader (SL-) ribonucleic acid (RNA) polymerase chain reaction (PCR) to screen for Leishmania infection. Of 1161 sand flies, the majority (77%) were P. longipes, six (0.5%) were P. orientalis and the remaining were Sergentomyia. The abundance of the 430 female P. longipes was significantly linked to seasonality (p < 0.001), with the majority in the dry season occurring in the outdoor rocky (37%) and peridomestic (34%) sites, while, in the wet season, most (62%) were captured indoors. This seasonality was more pronounced in rural Gindmeteaye, where housing construction is poor. The number of blood-fed and gravid P. longipes was significantly higher in the wet (31%; 22%), compared to the dry season (13%; 8%), and their proportion was highest indoors. Eighteen (4%) female P. longipes were Leishmania positive, with highest infection prevalence in caves (7% compared to 3% indoors, p = 0.022), and in the dry season (6%, p < 0.001). Phlebotomus orientalis specimens were all captured in May in rural Gindmeteaye, five indoors and one in a peridomestic site. Further research should be conducted to investigate the absolute contribution of humans and indoor transmission to the transmission cycle of CL. Inhabitants of endemic villages should be made aware that evening outdoor activities near caves may increase their exposure to infectious sand flies. Whether P. orientalis can breed and become infected at high altitudes should be further studied.

A review of the effect of medicinal plant extracts on Leishmania major in vitro and in vivo conditions in Iran

Background: Leishmaniasis is one of the most common parasitic diseases in tropical and subtropical regions of the world and is considered a threat to public health. Iran is also one of the most endemic areas of cutaneous leishmaniasis in the world. The causative species of cutaneous leishmaniasis is a protozoan from the Kinetoplastida order, which in Iran is Leishmania major (rural type) and Leishmania tropica (urban type). More than 70% of leishmaniasis in Iran is Leishmania major. The reservoir of the disease is humans in the urban type and field rodents in the rural type, and the vector is the female mosquito of the genus Phlebotomus. Methods: This study is organized as a review, in which, by searching the keywords cutaneous leishmaniasis, Leishmania major, plants effective against leishmaniasis in Iran, scientific-research articles, Google Scholar search engine information, Pubmed and Science Direct databases, the available books in this field were analyzed. Results: 5-valent antimoan compounds are used for the treatment of cutaneous leishmaniasis. Of course, not all patients need treatment because, in a large number of people, the lesion heals by itself, and due to the side effects of antimoan compounds, it is better to use fewer of these drugs. Therefore, the desire of patients and therapists to use herbal compounds has increased. Conclusion: Although cutaneous leishmaniasis is not usually associated with high Although cutaneous leishmaniasis is not usually associated with high mortality, the rate of infection is very high and causes malformed skin lesions that remain for more than a year in some cases, and even with standard treatment, scars remain. It remains forever and causes emotional pain for the patient. Therefore, domestic researchers have provided research on herbal treatments against Leishmaniasis, considering the history of traditional treatments in Iran and the scattered vegetation in the country.

Genetic diversity and phylogeography of Phlebotomus argentipes (Diptera: Psychodidae, Phlebotominae), using COI and ND4 mitochondrial gene sequences.

Phlebotomus argentipes complex is the primary vector for cutaneous leishmaniasis, a burgeoning health concern in contemporary Sri Lanka, where effective vector control is important for proper disease management. Understanding the genetic diversity of the P. argentipes population in Sri Lanka is vital before implementing a successful vector control program. Various studies have indicated that genetic divergence, caused by genetic drift or selection, can significantly influence the vector capacity of arthropod species. To devise innovative control strategies for P. argentipes, exploring genetic diversity and phylogeography can offer valuable insights into vector competence, key genetic trait transfer, and impact on disease epidemiology. The primary objective is to analyze the genetic diversity and phylogeography of the P. argentipes complex in Sri Lanka, based on two mitochondrial genomic regions in modern representatives of P. argentipes populations. A total of 159 P. argentipes specimens were collected from five endemic areas of cutaneous leishmaniasis and identified morphologically. Two mitochondrial regions (Cytochrome c oxidase subunit I (COI) and NADH dehydrogenase subunit 4 (ND4) were amplified using the total DNA and subsequently sequenced. Partial sequences of those mitochondrial genes were utilized to analyze genetic diversity indices and to explore phylogenetic and phylogeographic relationships. Among five sampling locations, the highest genetic diversity for COI and ND4 was observed in Hambantota (Hd-0.749, π-0.00417) and Medirigiriya (Hd-0.977, π-0.01055), respectively. Phylogeographic analyses conducted using COI sequences and GenBank retrieved sequences demonstrated a significant divergence of P. argentipes haplotypes found in Sri Lanka. Results revealed that they have evolved from the Indian ancestral haplotype due to historical- geographical connections of the Indian subcontinent with Sri Lanka. Utilizing high-mutation-rate mitochondrial genes, such as ND4, can enhance the accuracy of genetic variability analysis in P. argentipes populations in Sri Lanka. The phylogeographical analysis of COI gene markers in this study provides insights into the historical geographical relationship between India and P. argentipes in Sri Lanka. Both COI and ND4 genes exhibited consistent genetic homogeneity in P. argentipes in Sri Lanka, suggesting minimal impact on gene flow. This homogeneity also implies the potential for horizontal gene transfer across populations, facilitating the transmission of genes associated with traits like insecticide resistance. This dynamic undermines disease control efforts reliant on vector control strategies.

Anti-Leishmania activity of the Mayan medicinal plant Thouinia paucidentata Radlk extracts

Mexico’s Yucatan Peninsula is an endemic area of cutaneous leishmaniasis, locally known as the chiclero’s ulcer, and Mayan traditional medicine which refers to the use of Thouinia paucidentata Radlk, known as k’an chuunup. Aqueous and organic leaves extracts were evaluated against promastigotes and amastigotes of Leishmania mexicana. Toxicity tests of extracts were performed using Vero and J774A.1 macrophage cell lines. The composition of the most active extracts was analysed by GC-MS. The n-hexane and ethyl acetate extracts showed potent anti-Leishmania activity against the promastigote form, and remarkably, n-hexane extract exhibited potent activity against the amastigote form. Both extracts showed low toxicity on Vero both not on J774A.1 cells. Analysis of both bioactive extracts identified as more abundant compounds, germacrene D-4-ol and thunbergen in n-hexane, and thunbergol in ethyl acetate extracts. Our study presents T. paucidentata as anti-Leishmania phytomedicine supporting its medicinal use and contributes to the understanding of its phytochemical composition.

Ecological interactions of sand flies, hosts, and Leishmania panamensis in an endemic area of cutaneous leishmaniasis in Colombia.

The transmission dynamics of leishmaniasis are complex. There is also a lack of information about the ecological relationships between the vector/host/parasite at a more local and specific level. The Andean region concentrates more than 50% of Colombia's cutaneous leishmaniasis (CL) cases. The study of the ecological interactions of sand flies through the identification of blood sources has provided information on the female's opportunistic behavior, feeding on various hosts. Therefore, this study aimed to determine sand flies' ecological interactions with Leishmania parasites and their blood sources in an endemic area of CL. A total of 4,621 sand flies were collected, comprising 20 species, in which the most abundant were Nyssomyia yuilli yuilli (55.4%), Psychodopygus ayrozai (14.5%) and Ps. panamensis (13.4%). Sequences of 12S gene fragment were analyzed using the BLASTn search tool. Blood-meal source identification was successfully performed for 47 sand flies, detecting seven vertebrate species, human and armadillo being the most frequent. Leishmania DNA was amplified in four female pools, constituted by Ny. yuilli yuilli and Ps. ayrozai, and the identification through RFLP detected Leishmania (Viannia) panamensis in the positive pools. The interactions between the sand fly species, local mammalian fauna and the Leishmania parasite in this active focus of CL, provide evidence of the potential role of two different species in the maintenance of the parasite transmission, important information for the understanding of the ecoepidemiology and transmission dynamics of the disease in Andean endemic areas. However its necessary further evaluations of the vector and host competence in the transmission and maintenance of Leishmania spp, in these complex and diverse areas.

Diversity and temporal distribution of sand flies in an endemic area of cutaneous leishmaniasis in Centre-West Colombia.

The community structure of sand flies indicates the level of adaptation of vector species in a region, and in the context of vector management and control, this information allows for identifying the potential risks of pathogen transmission. This study aimed to analyze sand fly diversity and spatial-temporal distribution in an endemic area of cutaneous leishmaniasis. The study was carried out in the Carrizales hamlet (Caldas), between September 2019 and October 2021. The monthly distribution of sand fly species was evaluated through collections with CDC traps. Shannon and evenness indices were calculated and used to compare species frequencies at each house. The association between climatic variables and the frequency of sand flies was evaluated using Spearman's correlation. A total of 6,265 females and 1,958 males belonging to 23 species were found. Low diversity and evenness were observed, with the dominance of Nyssomyia yuilli yuilli (Young & Porter). Ecological and diversity indices did not reveal differences between the houses. The sand fly community was composed of 3 dominant species, Ny. yuilli yuilli, Psychodopygus ayrozai (Barretto & Coutinho), and Ps. panamensis (Shannon), representing 75.8% of the total catches. No statistical association was found between the absolute frequency of sand flies, rainfall, and temperature. The results show one dominant species, this fact has epidemiological relevance since density influences parasite-vector contact. The high densities of sand flies recorded in peri- and intradomiciliary areas highlight the necessity of periodic monitoring of vector populations and control activities to reduce the risk of Leishmania transmission in this endemic area.

Cutaneous leishmaniasis in an albino child: a peculiar presentation

Cutaneous leishmaniasis (CL) is the most common form of leishmaniasis. It is characterized by nodulo-ulcerative skin lesions and occasionally nodular, papular/plaque, and/or impetiginous lesions on exposed parts of the body. However, other atypical lesions of CL have been reported worldwide such as lupoid, eczematous, erysipeloid, verrucous, dry, zosteriform, paronychial, sporotrichoid, chancriform, annular and erythematous volcanic ulcers. These non-specific lesions often make the diagnosis challenging due to the large number of differential diagnoses and may lead to a delay in the implementation of CL therapy and therefore a higher risk of lifelong scars and major quality of life issues and stigma. We report a case of an 11-year-old immunocompetent albino child boy that presented with 3 years’ history of persistent multiple asymptomatic, small ulcers and cribriform scars of the forehead. Diagnosis of CL was confirmed by detecting Leishmania parasites in tissue specimens, and treatment by antimony drugs resulted in healing of lesion within one month. This is a novel case of a rare, atypical form of CL, which resulted in delayed diagnosis and management. Clinicians, especially those practicing in CL endemic areas like the Americas and the Mediterranean basin, should consider systematically the diagnosis of CL in front of long-lasting and/or non-specific lesions.

Epidemiological Characteristics and Endemicity of Zoonotic Cutaneous Leishmaniasis in Qom Province, Central Iran

Background and Objectives: Cutaneous leishmaniasis (CL) is a common parasitic disease in tropical and subtropical areas. This disease has become endemic in some parts of Qom province in central Iran. This study aims to determine the epidemiological characteristics and endemicity of zoonotic CL in Qom, Iran. Methods: In this cross-sectional study, out of 45 villages located in CL endemic areas in central and Kahak districts of Qom province, 8 villages were randomly selected. At the end of each season, the households were visited and their demographic information and history of infection with CL were recorded using standard forms. Results: Out of 4228 people living in 8 disease endemic villages, 1920(45.41%) had skin lesions and a history of infection with CL. We also found 165 new cases with active lesions. The prevalence of zoonotic CL was 71.49 per 1000 persons. Among patients, 13.33% were under 7 years of age and 67.87% aged &gt;15 years old. Therefore, zoonotic CL in the study area had a hypoendemic focus. Conclusion: The focus of zoonotic CL in Qom province is hypoendemic. Therefore, personal protection methods against sandfly bites such as the use of mosquito nets (especially insecticide-treated mosquito nets), the nets for doors and windows in residential areas, and the insect repellent compounds are recommended to control the disease in Qom.

Development of an Indirect Fluorescent Antibody (IFA) Assay for the Detection of Leishmania RNA Virus 2 (LRV2) in Leishmania Parasites.

Detection of Leishmania RNA virus (LRV) in Old World Leishmania species and their possible role in the disease prognosis requires sensitive and specific methods, preferably independent of the viral genome. We aimed to develop an indirect immunofluorescence antibody (IFA) assay to detect LRV in the Old World Leishmania parasites. Clinical samples were collected from 86 cutaneous leishmaniasis (CL) patients in different endemic areas of CL in Iran, during 2017-2019. For antibody preparation, the viruses were obtained from sediment of an LRV-infected L. major culture-using freeze and thaw cycles followed by gradient cesium chloride centrifugation. The purified viruses were used to immunize a male 3-4 months rabbit. Various dilutions of the LRV-immunized rabbit's serum and a conjugated antibody were deployed to detect LRV in 48 isolates by IFA assay. LRV virus was detected in four of the 48 CL cases using IFA method. Amplification of a partial fragment of RNA-dependent RNA polymerase (RdRp) gene from the isolates confirmed the IFA results. In phylogeny, the generated RdRp sequences from four isolates were grouped with the other Old World LRVs, but separate from L. aethiopica LRVs, which appeared as a highly supported distinct clade. Further optimization of this approach to detect the LRV directly in lesion scrapings can make it a more reliable tool for field studies and disclosing the virus's possible role in disseminating and unusual clinical features.

Population dynamics of phlebotomine sand flies (Diptera: Psychodidae) in cutaneous leishmaniasis endemic areas of Kurunegala District, Sri Lanka

Sand flies are the primary vectors of leishmaniasis. Disease management with effective vector control depends on the knowledge of vector population dynamics. In Sri Lanka, despite few isolated entomological collections, long-term studies are not reported to date. In the reported study, monthly entomological surveillance was conducted from May 2017 to December 2018 in Polpithigama, Maho, and Galgamuwa Medical Officer of Health (MOH) areas using standard entomological techniques. Climatic data were collected from the Department of Meteorology, Sri Lanka. Patient records were collected from each MOH office. A total of 38,339 sand flies were collected. The majority were Phlebotomus argentipes (99.50%, n = 38,147), while the rest was Sergentomyia punjabensis (0.50%, n = 192). Wind speed reduces sand fly abundance (r = -0.519, P < 0.05) evidently by limiting the movement. Rainfall increases sand fly abundance (r = 0.842, P <0.05, lag = 6 months) probably by improving favorable conditions in breeding sites. The actual effect of humidity is not conclusive without further research. The observed higher prevalence of leishmaniasis in the study sites could be due to the higher sand fly density in these areas. The number of patients shows a strong positive correlation (r = 0.516, P <0.05) to the sand fly abundance with a lag of 7 months. Systematic surveillance of sand flies as a part of general healthcare services is strongly recommended to identify and prevent possible outbreaks through timely planned vector control measures.

Cutaneous leishmaniasis-Awareness, knowledge and practices among general population in rural and urban areas in Malakand region, Pakistan.

Malakand region is an endemic area for cutaneous leishmaniasis (CL). However, there are limited number of studies of this disease in Pakistan. Therefore, a study was conducted to understand the level of awareness attitude and practice among the residents of Makaland towards CL and the disease vectors. This study adopted a cross-sectional approach with a total of 400 respondents (n=93 rural and n= 307 urban). Overall, the population in Malakand region (61.2%) were well-informed in the role of sand fly in transmitting diseases, but most lack knowledge on the vector's behavior and almost a quarter (24.5%) were unable to provide knowledge on proper control measures. Alarmingly, the practice and attitudes of the general population was not satisfactory as close to half (49.8%) of the population did adopt any control method. This study calls for increase in awareness through health education campaign to reduce the risk of cutaneous leishmaniasis outbreaks in the future.

Diagnostic Efficacy of Recombinase-Polymerase-Amplification Coupled with Lateral Flow Strip Reading in Patients with Cutaneous Leishmaniasis from the Amazonas Rainforest of Perú.

Cutaneous leishmaniasis (CL) is highly prevalent in rural and sylvatic regions of Latin America, with an estimated 55,000 annual cases. Diagnosis in resource-limited areas still relies on microscopy of dermal scrapings, while more sensitive methods like PCR are not attainable due to costs and lack of adequate health infrastructure. Isothermal amplification of Leishmania DNA can be performed without sophisticated equipment and training and may become a point of care (POC) test for health care centers with scarce resources. We evaluated the efficacy of recombinase-polymerase-amplification (RPA-LF) to diagnose CL in 226 patients attending a clinic in Puerto Maldonado within the Peruvian Amazon basin. Conventional PCR targeting kinetoplast DNA (kDNA-PCR) was used as the gold standard. Eight of 226 patients were considered true negatives (microscopy, kDNA-PCR, and RPA-LF negative), while RPA-LF resulted positive in 186 of 204 kDNA-PCR positive patients, yielding 91.2% (confidence interval [CI] = 86.5-94.4%) sensitivity and 93% (CI 88.6-95.8%) positive predictive value. There were 14% (32/226) discrepant samples alternating positive and negative results in similar proportions between both tests. Quantitative PCR used to resolve the discrepancies suggested that they occurred in samples with scarce parasite numbers as determined by high cycle threshold (Ct) values (≥32; cutoff 35.5). Microscopy had the lowest sensitivity of all methods (45.4%). Nested real-time PCR performed in 71 samples determined that Leishmania (Viannia) braziliensis was highly prevalent (69/71), and Leishmania (Viannia) lainsoni was present in only two isolates. Results indicated that RPA-LF has POC potential for CL endemic areas, yet further simplification and optimization coupled with field validation will be necessary to confirm its broad applicability.

An investigation of a new cutaneous leishmaniasis endemic area in Western Sri Lanka.

The aim was to investigate an emerging focus of cutaneous leishmaniasis (CL) in Gampaha district, Western Sri Lanka. Sociodemographics of CL patients in Mirigama, Gampaha district, were compared with controls using a structured questionnaire. Clinical data and geographic positioning system coordinates of patients were recorded. Sandflies collections were performed in four selected sites using indoor hand collection (162 units) and cattle-baited net traps (n=3). Of 73 patients (mean age 43.6 y; SD 20), 58.9% were males. Lesions consisted of nodules (52.1%) and ulcers (47.9%). Single lesions were seen in 69.9% of patients, while 30.1% had multiple lesions. Except for one mucosal lesion, all the others were cutaneous. Treatment consisted of sodium stibogluconate and cryotherapy (46.6%), sodium stibogluconate (45.2%) or cryotherapy (8.2%). Multiple lesions were more likely to receive combination therapy (p=0.013). The majority of those employed (81.1%; 27/33) were engaged in outdoor work. Male gender, low education attainment and poor disease awareness were significant risk factors for CL (p<0.05). Four households reported multiple cases. Phlebotomus argentipes was detected in all cattle-baited net traps and 35.3% of indoor hand collection units. CL is emerging in Gamapha district with Mirigama as the epicentre. Case distribution indicates local transmission, with P. argentipes as the probable vector.

Determination of sand fly fauna and molecular detection of Leishmania in sand flies in Antalya Province, Southern Turkey.

Visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) are diseases transmitted by infected female sand flies. Since the eradication of malaria in Turkey, CL is the main vector-borne disease in the country, with more than 2000 cases per year, making it a significant public health problem. The aims of this study were to carry out an entomological survey in Antalya Province, an endemic area for CL in the Mediterranean Region of Turkey, to identify sand fly fauna and to screen female specimens for the presence of Leishmania parasites (Leishmania infantum, L. tropica, L. major, and L. donovani) using molecular analysis. Sand flies were collected in 42 localities of seven districts in Antalya Province using CDC miniature light traps in two different periods, June 2012 and September 2013. The specimens were kept in 96% ethanol until the dissection was done. The head and genitalia of the specimens were cut for preparing individual slides for species identification. The rest of the body of female specimens was kept separately. The specimens were identified at the species level, and 27 pools were generated according to the locations and species for screening the presence of Leishmania. A commercial kit was used for DNA extractions. Real-time and conventional polymerase chain reaction (PCR) targeting the internal transcribed spacer region (ITS1) were then performed. In total, 1306 specimens comprising nine species belonging to the Phlebotomus genus were collected in the study region, with Phlebotomus neglectus/syriacus (38.82%) the most abundant, followed by P. alexandri (21.67%) and P. tobbi (20.44%). In the 27 pools, Leishmania infantum DNA was detected in four pools containing P. neglectus/syriacus and one pool containing P. tobbi. In conclusion, the sand fly fauna in the Antalya Province is diverse. The probable vector sand fly species are P. neglectus/syriacus and P. tobbi with high dominance (59.26%), which indicates a high risk of CL transmission. The data presented here may help to shed more light on the transmission cycles of the Leishmania parasite in this CL endemic area.

Molecular Identification of Leishmania Species in an Outbreak of Re-Emerged Cutaneous Leishmaniasis in Southwestern Iran During 2015 - 2016

Background: Dezful and its suburbs, as the second city in Khuzestan Province, southwest of Iran, has been an endemic area of cutaneous leishmaniasis (CL) with a low incidence rate since the last decades. However, the disease incidence has rapidly increased, and now is considered as a re-emerging parasitic disease in the area. Objectives: The aim of this study was to identify the most prevalent CL species in Dezful Region. Methods: A total of 196 microscopically confirmed slides from CL patients referred to Dezful Health Center were randomly collected in the period of 2015 - 2016. After DNA extraction from microscopically positive slides, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was carried out on 61 eligible specimens using ribosomal internal transcribed spacer 1 (ITS1) gene. The HaeIII restriction enzyme was used for the identification of species. Results: Samples were randomly collected from 196 acute CL cases, including 110 (56.2%) males and 86 (43.8%) females. Most infections were seen in the age range of 2 - 7 years (65/196, 33.1%). Totally, 60.1% of the cases had only one lesion, and half of the lesions appeared on hands. Furthermore, 162 (82.7%) cases were referred to Dezful Health Center in the cold seasons (autumn and winter). Results of PCR-RFLP on 61 eligible isolates showed that 60 (98.4%) isolates were Leishmania major, and only 1 (1.6%) isolate was Leishmania tropica. Conclusions: Our findings indicated that L. major is the main agent of re-emerged CL in Dezful and its suburbs, and the disease is a zoonosis.

Genetic diversity of Leishmania major strains isolated from Phlebotomus papatasi and Phlebotomus alexandri in western Iran based on minicircle kDNA.

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 14isolates 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.

Diagnosis and identification of Leishmania species in patients with cutaneous leishmaniasis in the state of Roraima, Brazil's Amazon Region

BackgroundCutaneous leishmaniasis (CL) is an endemic disease in Brazil that is highly prevalent in the northern region of the country. Although there is a continuous and growing number of cases registered in the state of Roraima, there is limited information regarding the species of Leishmania that affect the human population. In this study, we aimed to characterize which Leishmania species cause human disease in those presenting with cutaneous leishmaniasis in endemic areas of the State of Roraima.MethodsWe conducted a prospective surveillance study between 2016 to 2018 in health centers located in the State of Roraima, Brazil. Participants with clinical suspicion of CL were enrolled and provided lesion samples for parasitological detection by microscopy. A subset of the samples was tested by polymerase chain reaction and sequencing of the internal transcribed spacer 1 (ITS-1 PCR) for molecular species identification.ResultsA total of 262 participants were enrolled in this study. Of those, 129 (49.27%) were positive by parasitological examination. Most positive subjects (81.58%) were male, and most cases presented a single lesion (80.26%). ITS-1 PCR and sequencing on a subset of 76 samples allowed us to detect nine different species of Leishmania: L. (V.) braziliensis, L (V.) panamensis, L. (V.) guyanensis, L. (V.) naiffi, L. (V.) shawi, L.(V.) utingensis, L. (V.) lindenbergi, L. (L.) amazonensis and L. (L.) mexicana.ConclusionsOur study provides the first assessment of circulating species of Leishmania in the State of Roraima, Brazil, and shows the high diversity in this region. This study opens the path for further research on the transmission of leishmaniasis in the northernmost Brazilian State including vector and reservoir surveillance as well as for intensification of investigation and control activities against CL in the region.Graphical

Cutaneous Leishmaniasis (CL): A Cross-Sectional Community Based Survey on Knowledge, Attitude and Practices in a Highly Endemic Area of Waziristan (KPK Province), Pakistan

Recent outbreaks of Cutaneous Leishmaniasis (CL) in Waziristan make the disease a public health concern in Khyber Pakhtunkhwa (KPK) province, Pakistan. The awareness and behavior of local community towards the disease is an important factor towards effective control and management of CL in endemic areas of Pakistan. A cross-sectional community based survey was piloted in new emerging district of North Waziristan Agency (KPK province), Pakistan from August 2019- February 2020. The study aimed to examine the Knowledge, Attitude and Practices (KAP) of the local community members regarding CL. The results revealed that majority of the participants were male. Only 48.2% participants have knowledge about CL and the respondents had a moderate knowledge of CL vector and the disease. Few of the respondents were aware that CL is caused by sand flies, their breeding place, biting time, transmission of CL and control measures. Skin infection and sand-flies were the main disease symptoms and disease vector were known to some of the respondents. Most of the respondents showed positive attitude towards disease seriousness and believed that the disease could be cured and can be treated through modern medicines. Admission to hospitals, cleanliness and use of bed nets were the treatment measures for the disease in suspected patients, whereas some believed that the use of bed nets could be helpful in preventing the leishmaniasis. Moderate knowledge of the CL and its transmission in the study area emphasize the need to initiate health education and awareness campaigns to reduce the disease risk and burden in this highly endemic area in near future.

Time Series Analysis of Cutaneous Leishmaniasis in Sabzevar Northeastern Iran Using Segmented Regression Model

Background and aims: Cutaneous leishmaniasis (CL) is one of the most important parasitic diseases in the world. Sabzevar city is endemic area for CL in the north east of Iran. The aim of this study was to evaluate the time distribution of cutaneous leishmaniasis (CL) in Sabzevar County using the segmented regression model. Methods: This ecological study used the existing data related to the rural districts of Sabzevar County that were obtained from the Health Deputy of this county during 2011-2017. In addition, the segmented regression model was applied to evaluate the time trend of CLs. Finally, Joinpoint software was used for time series analysis. Results: A total of 1912 CL cases occurred in Sabzevar County from 2011 to 2017, with an incidence rate of 93.61 per 100000. The highest and lowest observed incidence rates were in 2011 (25 per 10000 persons) and 2015 (3.24 per 10000 persons), respectively. Based on the results, the annual incidence of CL in the intended region decreased and the annual percent change was equal to -22.40. Further, the time series analysis using segmented regression by rural districts showed a change point in the trend of the incidence of leishmaniasis in three rural districts (Pain Joveyn and Joghatai in 2014 and Qasabeh-ye Sharqi in 2013). In other words, the trend was different before and after the change point in the mentioned districts. Conclusion: In general, the results indicated that interventional, preventive, and therapeutic measures for breaking the chain of CL transmission in Sabzevar have been desirable in recent years. Eventually, it is suggested that further time-series studies be conducted at the level of the month or a longer interval in order to better evaluate the period effect and secular trend.

Cutaneous leishmaniasis: A pathological study of 360 cases with special emphasis on the contribution of immunohistochemistry and polymerase chain reaction to diagnosis

Traditional methods for the diagnosis of leishmaniasis yield poor sensitivity, which limits its effectiveness in lesions with a low parasite burden. Retrospective pathologic study of 360 cases of cutaneous leishmaniasis and analysis of the different diagnostic methods used. In 93% of the lesions, histopathology showed a dense and diffuse inflammatory infiltrate, consisting of lymphocytes, histiocytes and plasma cells, which occupied the superficial and mid dermis and variably extended to deep dermis and superficial subcutis (standard pattern). The remaining cases exhibited atypical features, such as perivascular, interstitial or perifollicular inflammatory patterns, folliculitis or panniculitis. Granulomas were identified in 84% of biopsies, most of them as small, poorly formed, non-necrotizing histiocytic aggregates. Amastigotes were visualized by routine histopathologic exam in 36% of biopsies. Immunohistochemistry stained 17 of 26 lesions (65%) negative by conventional stains. PCR provided the correct diagnosis in 218 cases (58% of the series) negative for Leishmania by other techniques. Biopsies negative for Leishmania by traditional diagnostic methods that show the histopathologic standard pattern, those with atypical features from patients with clinical suspicion of cutaneous leishmaniasis in endemic areas, should be studied by immunohistochemistry and/or PCR for Leishmania in order to reach the definitive diagnosis.