Search Results (421)

Leishmaniasis, a vector-borne neglected tropical disease, affects over 6.2 million people globally. Case acquisition is increasingly recognized in the United States, and in Texas, most reported cases are locally acquired and speciated to Leishmania mexicana. We conducted a scoping literature review to systematically assess contemporary research on Leishmania in humans, animals, reservoir hosts, or vectors in Texas after 2000. Out of 22 eligible studies, the most prevalent themes were case reports, followed by studies on domestic animals, reservoirs, and vectors, with several studies bridging multiple disciplines. Climate change, urbanization, and habitat encroachment appear to be driving the northward expansion of L. mexicana, which is primarily attributed to shifts in the habitats of key vectors (Lutzomyia anthophora) and reservoirs (Neotoma spp.). Leishmania appears to be expanding into new areas, with potential for further spread. As ecological conditions evolve, strengthening surveillance and clinician awareness is crucial to understanding disease risk and improving early detection and treatment in affected communities. Full article

Human cutaneous leishmaniasis (CL) caused by Leishmania (Viannia) braziliensis is a complex parasitic disease marked by dynamic host–parasite interactions and immunomodulation. Extracellular vesicles (EV) derived from immune cells have emerged as key mediators of intercellular communication and potential biomarkers in infectious diseases. In this study, we combined a modified lymphocyte proliferation assay with nano-flow cytometry to quantify and phenotype EV released by CD4⁺, CD8⁺, and CD14⁺ cells in PBMC cultures from CL patients at different clinical stages: before treatment (PBT), during treatment (PDT), and post-treatment (PET) with antimonial. Healthy individuals (HI) were included as physiological controls. Upon stimulation with L. (V.) braziliensis antigens, we observed a distinct modulation of EV subsets. In the PBT group, CD4⁺ and CD14⁺ EV were significantly reduced, while CD8⁺ EV remained elevated. During PDT and PET, EV concentrations were restored across all subsets. These findings suggest that L. (V.) braziliensis selectively modulates the release of immune cell–derived EV, possibly as an immune evasion mechanism. The restoration of EV release following antimonial therapy highlights their potential as sensitive biomarkers for disease activity and treatment monitoring. This study offers novel insights into the immunoregulatory roles of EV in CL and underscores their relevance in host–parasite interactions. Full article

This article describes a new software architecture for the non-invasive detection of canine leishmaniasis disease. The proposed platform combines gas-sensing technologies, artificial intelligence (AI), and modular cloud-based software components to identify disease-specific volatile organic compounds (VOCs) found in dog breath and hair samples. The system, which has a multi-tier architecture that includes data collection, pre-processing, machine learning-based analysis, diagnosis-request processing, and user interfaces for veterinarians, faculty researchers, and dog owners, has been integrated into a Li-ion Power website plug-in. The primary goal of implementing the proposed platform is to detect parasites at any point they are infectious to a host. This includes detecting parasites at all stages of their life cycle, where they can infect a new host. In addition, this is crucial for accurate diagnosis, effective treatment, and preventing further transmission. Full article

Leishmaniasis is an infectious disease common in tropical and subtropical regions worldwide. This study aimed to develop a topical meglumine antimoniate gel (MA-gel) for the treatment of cutaneous leishmaniasis. The MA-gel was characterized in terms of morphology, pH, swelling, porosity, rheology, and thermal properties by differential scanning calorimetry (DSC). Biopharmaceutical evaluation included in vitro drug release and ex vivo skin permeation. Safety was evaluated through biomechanical skin property measurements and cytotoxicity in HaCaT and RAW 267 cells. Leishmanicidal activity was tested against promastigotes and amastigotes of Leishmania infantum, and in silico studies were conducted to explore possible mechanisms of action. The composition of the MA-gel included 30% MA, 20% Pluronic^® F127 (P407), and 50% water. Scanning electron microscopy revealed a sponge-like and porous internal structure of the MA-gel. This formula exhibited a pH of 5.45, swelling at approximately 12 min, and a porosity of 85.07%. The DSC showed that there was no incompatibility between MA and P407. Drug release followed a first-order kinetic profile, with 22.11 µg/g/cm² of the drug retained in the skin and no permeation into the receptor compartment. The MA-gel showed no microbial growth, no cytotoxicity in keratinocytes, and no skin damage. The IC₅₀ for promastigotes and amastigotes of L. infantum were 3.56 and 23.11 µg/mL, respectively. In silico studies suggested that MA could act on three potential therapeutic targets according to its binding mode. The MA-gel demonstrated promising physicochemical, safety, and antiparasitic properties, supporting its potential as a topical treatment for cutaneous leishmaniasis. Full article

Background/Objectives: Leishmaniasis is a zoonotic and anthropozoonotic disease with significant public health impact worldwide and is classified as a neglected tropical disease. The search for new affordable treatments, particularly oral and/or topical ones that are easy to administer and have fewer side effects, remains a priority for the scientific community in this field of research. In previous investigations, 3-alkoxy-1-benzyl-5-nitroindazole derivatives showed remarkable in vitro results against Leishmania species, and predictions of absorption, distribution, metabolism, excretion, and toxicity properties, as well as pharmacological scores, of the compounds classified as active were superior to those of amphotericin B, indicating their potential as candidates for in vivo studies. Therefore, the aim of the present study was to evaluate the in vivo antileishmanial activity of the indazole derivatives NV6 and NV16. Methods: The compounds were administered intralesionally at concentrations of 10 and 5 mg/kg in a BALB/c mouse model of cutaneous leishmaniasis caused by Leishmania amazonensis. To evaluate the efficacy of the compounds, indicators such as lesion size, ulcer area, lesion weight, and parasitic load were determined. Amphotericin B was used as a positive control. Results: The compound NV6 showed leishmanicidal activity comparable to that observed with amphotericin B, with a significant reduction in lesion development and parasite load, while NV16 caused a reduction in ulcer area. Conclusions: These results provide strong evidence for the antileishmanial activity of NV6 and support future studies to improve its pharmacokinetic profile, as well as the investigation of combination therapies with other chemotherapeutic agents currently in use. Full article

Localised cutaneous leishmaniasis (LCL) is a common neglected tropical disease in Ethiopia, which is mainly treated with intralesional (IL) pentavalent antimonial such as sodium stibogluconate (SSG) and/or cryotherapy. Both treatments are painful, and studies are lacking on the pain associated with these or affected individuals’ experiences of them. A cross-sectional, observational study was conducted at ALERT Comprehensive Specialized Hospital, Addis Ababa/Ethiopia. The socio-demographic and clinical data of individuals affected by LCL receiving IL SSG and/or cryotherapy was gathered, and their treatment was observed. Participants quantified their treatment-associated pain using the Wong–Baker Pain Scale. Health-related quality of life was measured using the (Children’s) Dermatology Life Quality Index. Adverse effects, participant experiences with local therapies, and dermatologists’ experiences and opinions of local LCL treatment were assessed using structured questionnaires. Of the thirty-six individuals with LCL included (64% male, 14% children), 52% reported a treatment-associated pain score ≥ 8. Cryotherapy administered with a cotton bud was associated with lower pain scores ≤ 6 (odds ratio: 0.15, 95% confidence interval: 0.03–0.89) compared to a cryotherapy spray device. There was wide variation in treatment administration. Local LCL treatment is painful, and most individuals experience significant pain. This study highlights the need for less painful but effective treatments, structured training, and clear standard operating procedures. Full article

Background/Objectives: Leishmaniasis remains a neglected tropical disease, with nearly one million new cases annually and limited investment in research. Current treatments, primarily based on pentavalent antimonials, are associated with severe side effects and increasing resistance. This study aims to develop a novel therapeutic strategy using a nanomaterial functionalized with sialic acid (SA) and colchicine (COL) to selectively target Leishmania braziliensis parasites. Methods: A nanostructured system was engineered by functionalizing its surface with SA and COL. SA was chosen to mimic host cell surfaces, enhancing parasite attraction, while COL was selected for its known leishmanicidal properties. The nanomaterial was designed to concentrate extracellular parasites on its surface via SA-mediated interactions, thereby increasing local COL efficacy. Results: The functionalized nanomaterial demonstrated a dual mechanism: SA facilitated the selective accumulation of Leishmania braziliensis parasites on the nanostructure surface, while COL exerted a cytotoxic effect. This synergistic interaction resulted in enhanced parasite mortality in vitro, suggesting improved selectivity and potency compared to conventional treatments. Conclusions: The proposed nanomaterial offers a promising alternative for leishmaniasis treatment by combining targeted parasite attraction with localized drug delivery. This strategy may reduce systemic toxicity and improve therapeutic outcomes. Full article

Background/Objectives: Cutaneous leishmaniasis is an infectious disease that most frequently affects neglected populations. Besides its incidence, a high disease burden is associated with the possibility of mucosal sequelae. Clinical follow-up of these patients is difficult due to the limited access of the affected population to healthcare and the long lapse between the development of cutaneous and mucosal diseases. In this study, we evaluated the positivity of L. V. braziliensis DNA on the nasal mucosa of patients treated for leishmaniasis in an attempt to estimate the possible long-term risk of developing mucosal leishmaniasis and its association with important clinical characteristics. Methods: Samples were collected immediately after treatment completion using a nasal swab and specific DNA was amplified and detected using real-time PCR. Clinical and laboratorial data was systematically collected. Results: The positivity of L. V. braziliensis was 7% after treatment, and of this 60% had mucosal lesions before treatment, compared with only 13.4% in patients negative for L. V. braziliensis after treatment (p = 0.031). Conclusions: Molecular detection of L. V. braziliensis DNA on the nasal mucosa is a promising strategy to improve the follow-up and treatment of patients with American Tegumentary Leishmaniasis. Full article

Leishmaniasis is a significant public health concern, affecting millions and causing substantial mortality, thus urgently requiring more effective and safer treatments. This study explored the potential of 33 novel N-acylhydrazone-derived compounds against Leishmania amazonensis parasites, focusing on their inhibition of the Leishmania arginase enzyme and promastigote growth. Compounds 8 and 18 showed over 90% inhibitory activity against promastigote cultures after 72 h of treatment. Compound 8 showed an IC₅₀ of 10.5 µM (9.4–11.8 µM), while compound 18 exhibited an IC₅₀ of 42.8 µM (41.3–44.4 µM). The antipromastigote effects of these compounds highlight their potential for further new drug design. These findings offer a promising starting point for addressing the pressing need for new therapeutic options against leishmaniasis. In addition, we used web-based tools to predict the compounds’ toxicity and pharmacokinetic parameters. Despite the lack of inhibition against the L. amazonensis arginase enzyme, further investigation into the mechanisms of action of these compounds and in vivo efficacy could contribute to the development of safer and more effective treatments for this neglected tropical disease. Full article

Visceral leishmaniasis (VL), a chronic disease caused by Leishmania infantum, is more prevalent in males than females. Control strategies that do not take this disparity into account can be suboptimal. We extended a sex-structured VL model by introducing four control variables: insecticide-treated bed nets, vector control, medical treatment, and animal culling. The study evaluates six intervention strategies and calculates the incremental cost-effectiveness ratio to assess their impact on disease transmission and cost-effectiveness. The analysis shows that, without interventions, the disease remains endemic with significant health and socioeconomic consequences. The proposed strategy, which applies all four controls, emerges as the most effective and cost-efficient strategy, leading to an exponential reduction in disease prevalence across human, vector, and animal populations. Strategies without animal culling and vector control followed in effectiveness. Moreover, it was found that applying up to 50% of the controls to females, compared to males, can still eliminate VL within the planning period. Full article

Background/Objectives: Timely and effective clinical management of leishmaniasis depends on a deep understanding of parasite biology and drug resistance mechanisms. Phosphatidylinositol-specific phospholipase C (PI-PLC) enzymes are critical for parasite survival and immune evasion and possibly influence treatment outcomes. This study aimed to characterize the PI-PLC gene family in the Leishmania infantum and Leishmania major genomes, with a focus on their expression profiles in antimony-susceptible and -resistant strains to uncover their diagnostic and prognostic relevance. Methods: This study conducted a comprehensive genome-wide screening to identify PI-PLC genes in L. infantum and L. major, followed by detailed analyses of their gene structures, conserved motifs, chromosomal localization, and phylogenetic relationships. To explore potential roles in drug resistance and clinical prognosis, RNA-seq data from antimony-resistant and -susceptible L. infantum strains were analyzed for differential gene expression. Results: Twenty-two PI-PLC genes were identified in each species, displaying conserved catalytic domains and diverse biochemical characteristics. Phylogenetic and chromosomal analyses revealed gene clustering and distribution patterns. Importantly, expression profiling highlighted several PI-PLC genes with differential regulation in resistant strains, suggesting a role in treatment response and potential as molecular markers. Conclusions: Our findings suggest that PI-PLC genes may be associated with drug susceptibility in L. infantum, warranting further functional investigation to validate their role as potential molecular markers. Full article

Vector-borne diseases (VBDs) significantly impact global child health, with mosquito-transmitted infections like malaria and arboviruses accounting for a substantial portion of this burden. However, other arthropod-borne diseases—transmitted by vectors such as ticks, fleas, sand flies, lice, and triatomine bugs—also pose serious health risks to children worldwide. This review specifically excludes mosquito-borne diseases to concentrate on these less-discussed yet clinically important pediatric VBDs. We examine their clinical manifestations, diagnostic challenges, and treatment options, highlighting the unique vulnerabilities of children, including immature immune systems, behavioral factors, and communication barriers that can delay diagnosis. Additionally, we explore how environmental and anthropogenic factors, such as climate change and urbanization, are expanding the geographic range of these vectors, leading to the emergence of diseases like Lyme disease and leishmaniasis in new regions. By focusing on non-mosquito VBDs, this review aims to raise awareness and inform healthcare providers and public health practitioners about the comprehensive landscape of pediatric vector-borne diseases. Full article

Leishmaniasis are infectious diseases caused by several parasitic species of Leishmania, mainly transmitted by the bite of infected phlebotomine sandflies. Humans, dogs, rodents, and other domestic and wild animals can act as reservoir hosts for the different Leishmania species. It is a neglected tropical disease that is endemic in Asia, the Middle East, North and East Africa, the Mediterranean region, and South and Central America. Clinical manifestations and disease severity depend on the species of the infecting parasites and the immunity status of the host. Leishmania represses the protective host immune response by manipulating the macrophage function, subverting cytokine expression to favor its survival and dissemination. A balance between pro-inflammatory and regulatory cells is necessary to bring a positive outcome. Accurate diagnosis and effective treatment represent the cornerstone in the control of this disease, although these are difficult in an environment of precariousness and poverty. Some recent studies highlighted the progressing work on diagnosis and treatments, such as the development of new benzimidazole-triazole derivatives for blocking the parasite growth, feline leishmaniasis with a comparison of immune responses in cats and dogs, and a transglutaminase that has been purified from L. infantum. The results of these studies could open new avenues in combating leishmaniasis. Full article

Background: Leishmaniasis is a vector-borne zoonotic disease caused by protozoa of the genus Leishmania. While it is endemic in the Mediterranean Basin and the Balkans, Romania remains a non-endemic country. However, climate change, increased international travel, and the documented presence of competent vectors (Phlebotomus spp.) have raised concerns about the potential emergence of autochthonous cases. Case Presentation: We report two cases of imported cutaneous leishmaniasis (CL) diagnosed in central Romania, a region without previously confirmed human or animal cases. The first case involved a 31-year-old male with a recent travel history to Spain, presenting with erythematous papules and plaques that evolved into ulcerated lesions. The diagnosis was confirmed histopathologically and by a PCR. Treatment with miltefosine was effective, with minimal hepatic toxicity and a sustained response at a six-month follow-up. The second case concerned an 11-year-old boy who had traveled to Elba, Italy. He developed ulcerative lesions that progressed rapidly and were complicated by Pseudomonas aeruginosa superinfection. Despite an initially negative smear, PCR testing of the skin lesion confirmed the presence of CL. Antifungal therapy with fluconazole led to clinical improvement; treatment was ongoing at the time of publication. Discussion: These cases highlight the diagnostic and therapeutic challenges associated with CL in non-endemic settings. The varied clinical evolution underscores the importance of considering leishmaniasis in the differential diagnosis of chronic, non-healing cutaneous lesions, particularly in patients with a travel history to endemic regions. Conclusions: Increased awareness among clinicians, supported by accurate diagnostic tools and public health surveillance, is essential to identify and manage imported leishmaniasis. Given the absence of a licensed vaccine and the growing risk of vector expansion in Eastern Europe, these cases support the WHO’s inclusion of leishmaniasis among the priority neglected tropical diseases targeted for intensified global control efforts by 2030. Full article

Parasitic diseases represent a severe global burden, with current treatments often limited by toxicity, drug resistance, and suboptimal efficacy in chronic infections. This review examines the emerging role of triazole-based compounds, originally developed as antifungals, in advanced antiparasitic therapy. Their unique structural properties, particularly those of 1,2,3- and 1,2,4-triazole isomers, facilitate diverse binding interactions and favorable pharmacokinetics. By leveraging innovative synthetic approaches, such as click chemistry (copper-catalyzed azide–alkyne cycloaddition) and structure-based design, researchers have repurposed and optimized triazole scaffolds to target essential parasite pathways, including sterol biosynthesis via CYP51 and other novel enzymatic routes. Preclinical studies in models of Chagas disease, leishmaniasis, malaria, and helminth infections demonstrate that derivatives like posaconazole, ravuconazole, and DSM265 exhibit potent in vitro and in vivo activity, although their primarily static effects have limited their success as monotherapies in chronic cases. Combination strategies and hybrid molecules have demonstrated the potential to enhance efficacy and mitigate drug resistance. Despite challenges in achieving complete parasite clearance and managing potential toxicity, interdisciplinary efforts across medicinal chemistry, parasitology, and clinical research highlight the significant potential of triazoles as components of next-generation, patient-friendly antiparasitic regimens. These findings support the further optimization and clinical evaluation of triazole-based agents to improve treatments for neglected parasitic diseases. Full article