Cases Of Visceral Leishmaniasis Research Articles

Visceral leishmaniasis–human immunodeficiency virus coinfection in a 52-year-old male in southwest Iran: a case report

BackgroundLeishmaniasis is a rare infectious disease observed in subtropical and tropical areas. This disease that demonstrates different clinical characteristics is caused by intracellular Leishmania protozoan. One of the important countries facing the incidence of this infectious disease is Iran. Recently, human immunodeficiency virus–Leishmania coinfection has been indicated in Iran.Case presentationIn the present case report, we show an atypical case of severe visceral leishmaniasis in a 52-year-old Iranian-Arab male with positive human immunodeficiency virus status. Leishmaniasis was detected by node biopsy and subsequently histopathology evaluations and confirmed by molecular methods.ConclusionsThe current study was the first report of an atypical case of a patient with Leishmania–human immunodeficiency virus coinfection in southwestern Iran, which was not responsive to the treatment. Therefore, the health authorities should be aware of these reports, which require permanent clinical follow-up of the patients as well as effective treatments.

Parasite Detection in Visceral Leishmaniasis Samples by Dye-Based qPCR Using New Gene Targets of Leishmania infantum and Crithidia.

Visceral leishmaniasis (VL) is a neglected disease considered a serious public health problem, especially in endemic countries. Several studies have discovered monoxenous trypanosomatids (Leptomonas and Crithidia) in patients with VL. In different situations of leishmaniasis, investigations have examined cases of co-infection between Leishmania spp. and Crithidia spp. These coinfections have been observed in a wide range of vertebrate hosts, indicating that they are not rare. Diagnostic techniques require improvements and more robust tools to accurately detect the causative agent of VL. This study aimed to develop a real-time quantitative dye-based PCR (qPCR) assay capable of distinguishing Leishmania infantum from Crithidia-related species and to estimate the parasite load in samples of VL from humans and animals. The primer LinJ31_2420 targets an exclusive phosphatase of L. infantum; the primer Catalase_LVH60-12060_1F targets the catalase gene of Crithidia. Therefore, primers were designed to detect L. infantum and Crithidia sp. LVH60A (a novel trypanosomatid isolated from VL patients in Brazil), in samples related to VL. These primers were considered species-specific, based on sequence analysis using genome data retrieved from the TriTryp database and the genome assembling of Crithidia sp. LVH60A strain, in addition to experimental and clinical data presented herein. This novel qPCR assay was highly accurate in identifying and quantifying L. infantum and Crithidia sp. LVH60A in samples obtained experimentally (in vitro and in vivo) or collected from hosts (humans, dogs, cats, and vectors). Importantly, the screening of 62 cultured isolates from VL patients using these primers surprisingly revealed that 51 parasite cultures were PCR+ for Crithidia sp. In addition, qPCR assays identified the co-infection of L. infantum with Crithidia sp. LVH60A in two new VL cases in Brazil, confirming the suspicion of co-infection in a previously reported case of fatal VL. We believe that the species-specific genes targeted in this study can be helpful for the molecular diagnosis of VL, as well as for elucidating suspected co-infections with monoxenous-like trypanosomatids, which is a neglected fact of a neglected disease.

Diagnosis of visceral leishmaniasis in Ceará state, Brazil: A flow analysis of cases between 2007 and 2021.

To analyse the flow of cases of visceral leishmaniasis (VL) in the state of Ceará, Brazil, between 2007 and 2021. An ecological study was conducted using a spatial approach of newly confirmed cases of VL recorded in the Notifiable Diseases Information System. We identified individuals whose municipality of diagnosis differed from that of their residence. Flow maps, constructed using Tabwin 32 and ArcMap 9.2, allowed for the identification of the volume of traffic between the municipality of residence and that of initial care. There were 6775 confirmed VL cases. As a flow indicator, 178 counties had at least one resident diagnosed in another municipality in Ceará, with 2491 VL cases and an average trip of 79 km. The largest hub for receiving cases for diagnosis was the capital Fortaleza (1478 patients from 129 other municipalities), followed by Sobral, located in the northwestern region of Ceará (599 from 55 municipalities), and Barbalha, in the southern region (171 from 29 municipalities). In this southern region, 25 municipalities moved 55 people for treatment to Juazeiro do Norte and 11 municipalities moved 39 patients to Crato. A total of 255 patients with VL from 11 municipalities in other Brazilian states, mainly from the Northeast and North, were observed and notified in health services in Ceará. The major centres of VL diagnosis outside residence were in the cities of Fortaleza, Sobral, Barbalha, Juazeiro do Norte and Crato. There was also an outflow of cases from other municipalities located in the northeastern and northern regions of Brazil. The flows were more intense during the first triennium of the analysis and milder from 2019 to 2021. Understanding the diagnostic flow of VL helps in decision making and the development of public policies to improve the lives of the population.

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.

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. 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. 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). This primary finding indicates that several HLA genes have a potential role in the susceptibility of Iranian people to CL and VL.

A Visceral Leishmaniasis Case from the Black Sea region: Skin Lesions and Leishmania Donovanii Amastigotes in Bone Marrow.

A Visceral Leishmaniasis Case from the Black Sea region: Skin Lesions and Leishmania Donovanii Amastigotes in Bone Marrow.

A Rare Case of Visceral Leishmaniasis Diagnosed by Endoscopy in an Anemic Patient With HIV/AIDS

ABSTRACT Visceral leishmaniasis (VL) is a rare protozoan parasitic disease transmitted by sandfly vectors predominantly found in Asia and Central America. Although far less common than cutaneous leishmaniasis, VL carries a higher mortality burden because of its propensity to cause emaciation and marked anemia through bone marrow infiltration. Treatment is particularly challenging in patients coinfected with HIV before both infections work synergistically to perpetuate immunosuppression, further promoting higher viral loads and disease burden. In comparison with those without HIV, these patients have poorer treatment responses and higher rates of relapse. We describe a case of VL in an anemic patient with HIV/AIDS diagnosed during esophagogastroduodenoscopy. We also present challenges to treatment, adverse drug side effects, and long-term sequelae.

Visceral Leishmaniasis Caused by Leishmania Tropica.

In Turkey, the main causative agent of visceral leishmaniasis (VL) is Leishmania. infantum and the main causative agent of cutaneous leishmaniasis (CL) is Leishmania tropica. In this study, we aimed to discuss the possible mechanisms, clinical aspects, and threat of visceralizing L. tropica. This study includes seven cases of VL caused by L. tropica.Five patients were male (71%) and four were adults (57%). All the VL patients complained of fever and splenomegaly. Fatigue, pancytopenia, and hepatomegaly were present in six patients each (86%), while weight loss and gastrointestinal system (GIS) symptoms were present in 5 patients (71%). In this study, we have evaluated seven cases of visceralized L. tropica (VLT) in the context of the changing leishmaniasis epidemiology in Turkey. We have evaluated the possible mechanisms of visceralization; inter- and intraspecies genetic exchange with all the old world leishmaniasis agents present in the region, stress induced by inappropriate use of drugs, and possible ongoing adaptation mechanisms of Leishmania spp. The threat posed by VLT is significant as L. tropica is the most widespread and most common cause of leishmaniasis in Turkey. We do not know the vectorial capacity of the sand flies for the transmission of VLT strains or if these strains are in circulation in Turkey. Future studies should be carried out to investigate these issues as the transition of L. tropica from a mild disease-causing agent to a mortal one poses a significant public health concern for Turkey and Europe.

Reemergence of Visceral Leishmaniasis in Henan Province, China.

Visceral leishmaniasis (VL) was widely prevalent in Henan Province in the 1950s. Through active efforts by the government, there were no local cases reported from 1984 to 2015. In 2016, local VL cases reoccurred, and there was an increasing trend of VL cases in Henan Province. To provide a scientific control of VL, an investigation was conducted in Henan Province from 2016 to 2021. The data from VL cases were obtained from the Disease Surveillance Reporting System of the Chinese Center for Disease Control and Prevention. The rK39 immunochromatographic test (ICT) and PCR assay were performed among high-risk residents and all dogs in the patients' village. ITS1 was amplified, sequenced, and subjected to phylogenetic analyses. A total of 47 VL cases were reported in Henan Province during 2016-2021. Of the cases, 35 were local, and they were distributed in Zhengzhou, Luoyang, and Anyang. The annual average incidence was 0.008/100,000, showing an upward trend year by year (χ2 = 3.987, p = 0.046). Their ages ranged from 7 months to 71 years, with 44.68% (21/47) in the age group of 0-3 years and 46.81% (22/47) in the age group ≥15 years. The cases occurred throughout the year. The high-risk populations were infants and young children (age ≤3), accounting for 51.06% (24/47), followed by farmers at 36.17% (17/47). The ratio of males to females was 2.13:1. The positive rates of rK39 ICT and PCR were 0.35% (4/1130) and 0.21% (1/468) in the residents. The positive rates of rK39 ICT and PCR were 18.79% (440/2342) and 14.92% (139/929) in the dogs. The ITS1 amplification products in the patients and positive dogs were sequenced. The homology between the target sequence and Leishmania infantum was more than 98%. The phylogenetic analysis indicated that the patients and the positive dogs were infected by the same type of Leishmania, which was consistent with the strains in the hilly endemic areas in China. This paper showed that patients and domestic dogs were infected by the same type of L. infantum and that the positive rate in dogs was relatively high in Henan Province. Because the measures of patient treatment and culling of infected dogs were not effective in reducing VL incidence in Henan Province, it is urgent to develop new approaches for the control of VL, such as wearing insecticide-impregnated collars on dogs, treating the positive dogs, spraying insecticide for sandflies control, and improving residents' self-protection awareness to prevent the further spread of VL in Henan Province.

Leishmaniases in a tropical area of Brazil: a spatio-temporal analysis.

Leishmaniases are a group of tropical and neglected diseases caused by the protozoa of the genus Leishmania which are transmitted by insect sandflies. Despite of the major efforts undertaken at global level for the control of these diseases, a recent spreading to non-endemic areas been observed. In this study we analyzed the spatio-temporal distribution of Visceral Leishmaniasis (VL) and Tegumentary Leishmaniasis (TL) cases notified in a tropical region of Brazil. A retrospective evaluation was carried out using secondary data (e.g., demographics, origin, age and area of occurrence) of human patients obtained from 2009 to 2019. Choropleth maps with levels of color intensity represented the spatial distribution of VL and TL cases. Overall, 116 (10.5 ± 8.5) cases of leishmaniases were registered in the study area during the whole period. Of those, 61 (5.5 ± 5.5) and 55 (5 ± 4.3) were diagnosed as VL and TL, respectively. VL cases were recorded in 61.9% (13/21) and TL cases in 42.8% (9/21) of the municipalities. Most of the cases were predominantly notified in men from rural areas, and specifically for TL with an age range of 30-59years old. These findings will be useful to drive strategies of control (e.g., vector control, dog surveillance and notification of suspected cases) against these neglect diseases, preventing the spreading to non-endemic areas.

Visceral Leishmaniasis Associated with HIV Coinfection in Pará, Brazil.

Human visceral leishmaniasis (VL) is a zoonosis of great importance to public health due to its epidemiological diversity, with emphasis on the possibility of aggravation by coinfection with the human immunodeficiency virus (HIV). The aim was to study the epidemiological characteristics of VL cases associated with HIV coinfection in Pará. Methods. Reported cases of VL from January 2006 to December 2016 were investigated. A descriptive epidemiological method related to age, gender, area of residence and coinfection with HIV was used. To calculate variance and test equity, the F-test (Fisher) was performed. To observe the influence of one aspect on another, the chi-square was used to verify if there was dependence or independence between the variables. A total of 1171 cases of VL were reported during the study period. There was an annual mean of LV of 94.9, with a statistical difference (p<0.05) between age groups, with the highest number of cases being observed in children aged 1 to 4 years (27.16%). Males and the urban area had a higher number of cases. There were 57 cases of VL/HIV coinfection, with emphasis on the year 2013 and the municipality of Santarém, which had the highest number of cases. During the ten years studied, there was a correlation between coinfection VL/ HIV, with significant differences between patients with and without HIV who contracted VL (p<0.001). The data reveal the endemic nature of VL in the region, with a high percentage of infection in children living in urban areas. Although the studied region is not identified as a predominant area of HIV cases, this study showed a high annual average (10.3) of cases of VL/HIV coinfection being the first time that cases of VL/HIV coinfection were reported in the Mesoregion of the Lower Amazon and Southwest Pará.

Visceral leishmaniasis in Xinjiang Uygur Autonomous Region during the COVID-19 pandemic: a case report

To perform an epidemiological investigation on a case of visceral leishmaniasis reported from Shule County, Kashi Prefecture, Xinjiang Uygur Autonomous Region in 2021, so as to provide insights into differential diagnosis of visceral leishmaniasis during the COVID-19 pandemic. The epidemiological history of this case was collected, and the case was diagnosed for Leishmania infection with the immunochromatographic (rK39) strip test, bone marrow smear microscopy and PCR assay. The patient had typical clinical symptoms of leishmaniasis, including irregular fever, hepatosplenomeg- aly, low serum albumin and elevated globulin. Bone marrow smear microscopy identified L. donovani amastigotes, and both rK39 strip test and PCR assay were positive, while the case was tested negative for SARS-CoV-2. COVID-19 was therefore excluded and visceral leishmaniasis was diagnosed. Standard full-dose treatment with sodium stibogluconate was given, and no Leishmania was found on blood smears during the reexamination. No recurrence was found during the followup after discharge for hospital. During the COVID-19 pandemic, it is recommended to increase the perception of differential diagnosis of visceral leishmaniasis among first-contact doctors, and reinforce the capability of differential diagnosis and health education of visceral leishmaniasis among medical and healthcare institutions at all levels, to prevent missed diagnosis and misdiagnosis of visceral leishmaniasis.

Asymptomatic Leishmania donovani infection and associated factors among blood donors attending at Metema district Blood Bank, Northwest Ethiopia: a cross- sectional study

BackgroundEthiopia is one of the top 10 countries in the world where 90% visceral leishmaniasis cases are reported. Metema-Humera lowlands are the most important foci in Ethiopia. Blood transfusion in visceral leishmaniasis endemic foci in Ethiopia does not consider screening of visceral leishmaniasis during blood donation. The aim of this study is therefore, was to assess asymptomatic Leishmania donovani infection and associated factors among blood donors attending at Metema district Blood Bank, Northwest Ethiopia.MethodsA Health facility based cross-sectional study was conducted at Metema Blood Bank from February to March 2020. A total of 205 blood donors were eligible and participated in this study. Structured questionnaire were used to collect data on socio-demographic characteristics and perceived risk factors associated with asymptomatic visceral leishmaniasis among blood donors. Blood donors were screened using both rK39 and direct agglutination tests based on the manufactures’ instructions. Data were analyzed using SPSS version 20.0. Chi-square test was used to assess associations of Leishmania donovani infection with predisposing factors. Associations were considered statstically significant on P-value < 0.05 at 95% confidence level.ResultsOf the total 205 participants, 32(15.6%) were positive for asymptomatic Leishmania donovani infection at least by one of the diagnostic tests used. Eight (3.9%) and 30(14.6%) of the participants` were positive by the rK39 and direct agglutination tests, respectively. Six (2.9%) donors were tested positive by both diagnostic tests. Family history of visceral leishmaniasis (X²=11.334, P = 0.003) and having neighbors with history of visceral leishmaniasis (X²=5.923, P = 0.015) were significantly associated with asymptomatic Leishmania donovani infection among blood donors.ConclusionsThe prevalence of asymptomatic Leishmania donovani infection was 15.6%. Asymptomatic visceral leishmaniasis was significantly associated with donors’ family and neighbors’ history of infection. Therefore, laboratory screening of blood donors for visceral leishmaniasis in endemic areas will be mandatory. Moreover, this study will give base line information for future study in the country.

Evaluation of Recombinase Polymerase Amplification assay for monitoring parasite load in patients with kala-azar and post kala-azar dermal leishmaniasis.

The potential reservoirs of visceral leishmaniasis (VL) in South Asia include asymptomatic and relapsed cases of VL, along with patients with post kala-azar dermal leishmaniasis (PKDL). Accordingly, accurate estimation of their parasite load is pivotal for ensuring disease elimination, presently targeted for 2023. Serological tests cannot accurately detect relapses and/or monitor treatment effectiveness, and therefore, parasite antigen/nucleic acid based detection assays remain the only viable option. An excellent option is the quantitative polymerase chain reaction (qPCR) but the high cost, technical expertise and time involved precludes its wider acceptability. Accordingly, the recombinase polymerase amplification (RPA) assay operated in a mobile suitcase laboratory has emerged not simply as a diagnostic tool for leishmaniasis but also to monitor the disease burden. Using total genomic DNA isolated from peripheral blood of confirmed VL cases (n = 40) and lesional biopsies of PKDL cases (n = 64), the kinetoplast-DNA based qPCR and RPA assay was performed and parasite load expressed as Cycle threshold (Ct) and Time threshold (Tt) respectively. Using qPCR as the gold standard, the diagnostic specificity and sensitivity of RPA in naïve cases of VL and PKDL was reiterated. To assess the prognostic potential of the RPA, samples were analyzed immediately at the end of treatment or ≥6 months following completion of treatment. In cases of VL, the RPA assay in terms of cure and detection of a relapse case showed 100% concordance with qPCR. In PKDL following completion of treatment, the overall detection concordance between RPA and qPCR was 92.7% (38/41). At the end of treatment for PKDL, 7 cases remained qPCR positive, whereas RPA was positive in only 4/7 cases, perhaps attributable to their low parasite load. This study endorsed the potential of RPA to evolve as a field applicable, molecular tool for monitoring parasite load, possibly at a point of care level and is worthy of consideration in resource limited settings.

Epidemiological aspects of visceral leishmaniasis in Rio Grande do Norte, Brazil

Visceral Leishmaniasis (VL) is a parasitic disease caused by Leishmania protozoa and transmitted by the bite of sand fly insects. This study aimed to describe the epidemiological aspects of VL in Rio Grande do Norte (RN), using variables inserted in the Information System for Notifiable Diseases, for the period from 2013 to 2019. The chi-square test of independence was used with p&lt;0.05 considered statistically significant. 635 cases of VL were reported in RN, with stability of new cases in the analyzed period. 60% of cases were autochthonous, 84 (50.2%) municipalities in RN had autochthonous cases, with 70 (18.2%) cases in Natal and 58 (15.1%) in Mossoró. The most affected age group was 20-59 year old (57.3%) followed by 0-9 year old (23.8%), 10-19 year old (10.4%) and 60 year old or older (8.5%). There was a positive association between the 0-9 and 10-19 ranges with females and 20-59 with males (p=0.0001). Among the 532 individuals, 54.5% had a low level of education, and these, as well as the illiterate, associated with males (p=0.001). 85.3% of 612 cases were in black/brown group and 77.1% of 632 in urban/periurban residents. 27.6% of 500 were co-infected with HIV, 77.5% in males and 89.8% in adults. 70.7% progressed to cure and 6.8% died from VL. The study shows that the control measures adopted within the scope of the National Program for the Control of Leishmaniasis should be reassessed since there has been no decrease in cases, even though it has had stability over the years in Natal and a tendency to growth in Mossoró, the most affected areas. KEY WORDS: Visceral leishmaniasis; Leishmania; epidemiology.

Seroprevalence of Visceral Leishmaniasis in Children Up To 12 Years Old of Rural Areas from Kermanshah Province, Western Part of Iran.

After the earthquake in 2017 a few new cases of visceral leishmaniasis (VL) were reported from SarPol-e-Zahab district of Kermanshah Province, western part of Iran. This study was conducted to determine the seroprevalence in Kermanshah Province. This descriptive cross-sectional study was conducted on children up to 12 years of age from SarPol-e-Zahab County, Kermanshah Province, western part of Iran in 2021. For each individual, a questionnaire including age, sex, clinical features, history of the disease, and contact with canines as reservoir hosts of VL were completed, separately. To determine VL seroprevalence, blood samples were collected from the children and after centrifugation, the sera samples were separated and tested using Direct Agglutination Test (DAT) for detection of anti-L. infantum antibodies. Statistical analyses were performed using SPSS16. Totally, 13 persons were seropositive; 7 samples with titer 1:800, 3 samples had 1:1600, 2 samples had 1:3200 and 1 sample had 1:6400. None of the seropositive cases had a history of kala-azar. There was no significant difference between males and females at titers of anti-Leishmania specific antibodies. L. infantum infection is being circulated with low prevalence in children up to 12 years old from SarPol-e-Zahab County but it is necessary that the surveillance system is regularly monitored among physicians and public health managers in the studied areas.

Exposure to and infection by Leishmania infantum among domestic dogs in an area of the Cerrado biome, Maranhão, Brazil

Visceral Leishmaniasis is a serious public health problem and dogs are considered to be the main source of infection in urban areas. In Brazil, this disease is present in all regions, but with high concentration of cases in the Northeast, and the state of Maranhão is considered to be an endemic region. The aim of this study was to conduct an epidemiological, spatial, molecular and serological survey on Leishmania infantum among domestic dogs in the municipality of Belágua, Maranhão. Blood samples were collected from dogs and questionnaires were applied to their owners to obtain epidemiological data and risk factors relating to this zoonosis in the region. The coordinates of the dogs' homes were obtained to produce a disease risk map. Serological diagnoses were made using the indirect immunofluorescence reaction (IFAT) and the dual-path platform chromatographic immunoassay test (DPP®) (Bio-Manguinhos/FIOCRUZ, Brazil). A molecular investigation was undertaken using the polymerase chain reaction (PCR). Georeferencing was performed using the global positioning system (GPS) and cases of canine visceral leishmaniasis in the municipality were spatially represented and analyzed using QGIS version 3.16.6 (QGIS Development Team, 2021). A total of 205 blood samples were collected, of which 122 (59.51%) were seroreactive for L. infantum through IFAT, while the DPP test showed 84 reactive samples (40.97%). IFAT and DPP detected 16 positive animals simultaneously. One sample that was seroreactive through IFAT was also positive through PCR. In the clinical evaluation, it was observed that among the seropositive dogs, 112 (91.80%) were symptomatic and 10 (8.20%) were asymptomatic. In the spatial analysis, the Kernel density estimator enabled determination of the place at greatest risk of occurrence of the disease. The areas with the highest concentrations of cases were in districts with large quantities of precarious housing and lack of basic sanitation. This was the first report on the occurrence of L. infantum among dogs in the municipality of Belágua. The results show that canine visceral leishmaniasis is well dispersed in this municipality, thus putting at risk the human population.

Antileishmanial Activity of Cinnamic Acid Derivatives against Leishmania infantum

Leishmania infantum is the etiological agent of visceral leishmaniasis (VL) in South America, the Mediterranean basin, and West and Central Asia. The most affected country, Brazil, reported 4297 VL cases in 2017. L. infantum is transmitted by female phlebotomine sand flies during successive blood meals. There are no validated vaccines to prevent the infection and the treatment relies on drugs that often present severe side effects, which justify the efforts to find new antileishmanial drugs. Cinnamic acid derivatives have shown several pharmacological activities, including antiparasitic action. Therefore, in the present study, the biological evaluation of cinnamic acid and thirty-four derivatives against L. infantum is reported. The compounds were prepared by several synthesis methods and characterized by spectroscopic techniques and high-resolution mass spectrometry. The results revealed that compound 32 (N-(4-isopropylbenzyl)cinnamamide) was the most potent antileishmanial agent (IC50 = 33.71 μM) with the highest selectivity index (SI > 42.46), followed by compound 15 (piperonyl cinnamate) with an IC50 = 42.80 μM and SI > 32.86. Compound 32 was slightly less potent and nineteen times more selective for the parasite than amphotericin B (MIC = 3.14 uM; SI = 2.24). In the molecular docking study, the most likely target for the compound in L. infantum was aspartyl aminopeptidase, followed by aldehyde dehydrogenase, mitochondrial. The data obtained show the antileishmanial potential of this class of compounds and may be used in the search for new drug candidates against Leishmania species.

Genetic variability highlights the invasion route of the Lutzomyia longipalpis complex, the main vector of Visceral Leishmaniasis in Uruguay.

In the Americas, the sandfly Lutzomyia longipalpis is the main vector of the parasitic protozoa Leishmania infantum, the etiological agent of visceral leishmaniasis (VL). The Lu.longipalpis species complex is currently discontinuously distributed across the Neotropical region, from Mexico to the north of Argentina and Uruguay. During its continental spreading, it must have adapted to several biomes and temperature amplitudes, when founder events should have contributed to the high genetic divergence and geographical structure currently observed, reinforcing the speciation process. The first report of Lu.longipalpis in Uruguay was in 2010, calling the attention of Public Health authorities. Five years later, the parasite Le.infantum was recorded and in 2015 the first case of VL in canids was reported. Hitherto seven human cases by VL have been reported in Uruguay. Here, we publish the first DNA sequences from the mitochondrial genes ND4 and CYTB of Lu.longipalpis collected in Uruguay, and we used these molecular markers to investigate their genetic variability and population structure. We described four new ND4 haplotypes in a total of 98 (4/98) and one CYTB in a total of 77 (1/77). As expected, we were able to establish that the Lu.longipalpis collected in two localities (i.e. Salto and Bella Unión) from the north of Uruguay are closely related to the populations from neighbouring countries. We also propose that the possible route for the vector arrival to the region may have been through vegetation and forest corridors of the Uruguay River system, as well as it may have benefited from landscape modifications generated by commercial forestation. The ecological-scale processes shaping Lu.longipalpis populations, the identification of genetically homogeneous groups and the gene flow among them must be carefully investigated by using highly sensible molecular markers (i.e. genome wide SNPs) since it will help to the understanding of VL transmission and contribute to the planification of public policies on its control.

Detection of asymptomatic Leishmania infection in blood donors at two blood banks in Ethiopia.

Visceral leishmaniasis (VL) is a disease caused by Leishmania parasites. While predominantly transmitted by sandflies, cases of VL transmitted through blood transfusion have been reported, particularly in immunocompromised recipients. Although Leishmania parasites have been found in blood donors in some VL endemic areas, this has never been studied in East-Africa, where HIV prevalence is relatively high. We established the prevalence of asymptomatic Leishmania infection and associated socio-demographic factors among blood donors presenting at two blood bank sites (Metema and Gondar) in northwest Ethiopia between June and December 2020. Metema is located in a VL-endemic area; Gondar has historically been considered VL non-endemic but as an outbreak of VL has occurred around Gondar, it was defined as previously VL non-endemic. Blood samples were tested by the rK39 rapid diagnostic test (RDT), rK39 ELISA, direct agglutination test (DAT) and qPCR targeting kinetoplast DNA (kDNA). Asymptomatic infection was defined as positive by any of these tests in a healthy person. A total of 426 voluntary blood donors were included. The median age was 22 years (IQR, 19-28 years); 59% were male and 81% resided in urban areas. Only one participant had a history of VL and three had a family history of VL. Asymptomatic infection was detected in 15.0% (n = 32/213) in Metema and 4.2% (n = 9/213) in Gondar. The rK39 ELISA was positive in 5.4% (n = 23/426), the rK39 RDT in 2.6% (11/426), PCR in 2.6% (11/420) and DAT in 0.5% (2/426). There were six individuals with two positive tests: one positive on rK39 RDT and PCR and five positive on rK39 RDT and ELISA. The prevalence of asymptomatic infection was higher in Metema (VL-endemic) and males but was not associated with age, a history of VL amongst family members or living in a rural area. Antibodies against Leishmania and parasite DNA was detected in a substantial number of blood donors. Future research should be directed at better defining the risk to recipients, including parasite viability studies and longitudinal studies amongst recipients.

Epidemiological survey of human and canine visceral leishmaniasis cases in the municipality of São Luís in the period from 2019 to 2020

The objective was to describe the epidemiological profile of visceral leishmaniasis (VL) in the municipality of São Luís, Maranhão. To this end, a descriptive study was carried out from 2019 to 2020, using secondary data obtained from the Information System of Notifiable Diseases and provided by the São Luís Zoonoses Surveillance Unit. General and clinical characteristics of the disease were analyzed in cases registered in humans and dogs. The results showed that 78 cases of VL in humans were reported, with the following profile: male (74.36%), mixed race (73.08%), 20 to 29 and 40 to 49 years old (35.90%), incomplete elementary school education (37.18%), urban area (44.87%). Most were new cases (84.62%), with co-infection with the HIV virus (41.03%) and with evolution towards cure (82.50%). Among the dogs, 401 cases were reported, 49.63% male, without defined breed (56.86%), age between 1 and 3 years (38.15%). Most dogs were symptomatic (90.27%), with a prevalence of skin lesions (39.90%) and weight loss (15.96%). It is concluded that VL has a frequent occurrence in the city of São Luís, therefore it is necessary to intensify sanitary measures in particular the education of the local population to reach the desired effect.