Search Results (71)

Leishmaniasis is a tropical and subtropical disease caused by protozoans of the genus Leishmania, primarily transmitted to humans through the bite of sandflies. This neglected disease poses a serious global health challenge due to its spectrum of clinical manifestations, which can lead to potentially fatal outcomes. In Honduras, four clinical forms of leishmaniasis are present: ulcerative cutaneous leishmaniasis (UCL), mucosal leishmaniasis (ML), non-ulcerated cutaneous leishmaniasis (NUCL), and visceral leishmaniasis (VL). This study aims to identify spatial patterns of these four clinical forms of the disease in Honduras, utilizing epidemiological data from 2009 to 2016. Geographic Information System (GIS) analysis was employed for spatial assessment. Moran’s I was used to evaluate the data and reveal patterns, while Hot Spot Analysis identified statistically significant spatial clusters of high and low values. For UCL and NUCL, all Global Moran’s I p-values were below 0.001 throughout the study period. For VL, p-values were under 0.001 in 2010, 2013, and 2016. For ML, p-values were below 0.05 in 2009, 2011, 2014, and 2015. In conclusion, our findings demonstrate geographical segregation among the different clinical forms of leishmaniasis. Full article

Neglected tropical diseases (NTDs) constitute a group of infectious diseases that severely affect the health of impoverished populations, and the health, economies, and health systems of affected countries. Leishmaniasis and human African trypanosomiasis (HAT) are particularly notable, and malaria, despite not being neglected, is part of the “big three” (HIV, tuberculosis, and malaria) with high incidence, increasing the probability of infection by NTDs. Therefore, efforts are ongoing in the search for new drugs targeting the enzyme N-myristoyltransferase (NMT), a potential drug target that has been explored. Thus, we provide a review here that highlights the epidemiological data for these diseases and the importance of discovering new drugs against these agents. Here, the importance of NMT and its inhibitors is clear, with this study highlighting thiochromene, pyrazole, thienopyridine, oxadiazole, benzothiophene, and quinoline scaffolds, identified by computational methods followed by biological assays to validate the findings; for example, this study shows the action of the aminoacylpyrrolidine derivative 13 against Leishmania donovani NMT (IC₅₀ of 1.6 nM) and the pyrazole analog 23 against Plasmodium vivax NMT (IC₅₀ of 9.48 nM), providing several insights that can be used in drug design in further work. Furthermore, the selectivity and improvement in activity are related to interactions with the residues Val⁸¹, Phe⁹⁰, Tyr²¹⁷, Tyr³²⁶, Tyr³⁴⁵, and Met⁴²⁰ for leishmaniasis (LmNMT); Tyr²¹¹, Leu⁴¹⁰, and Ser³¹⁹ for malaria (PvNMT); and Lys²⁵ and Lys³⁸⁹ for HAT (TbNMT). We hope our work provides valuable insights that research groups worldwide can use to search for innovative drugs to combat these diseases. Full article

Cutaneous leishmaniasis (CL) is a vector-borne parasitic disease caused by protozoa of the Leishmania genus. Once confined to endemic regions such as the Middle East, Americas, North Africa, and Central Asia, CL is increasingly emerging in non-endemic areas due to a multitude of drivers, including population displacement, environmental disruption, and political instability. These overlapping drivers contribute to expanding sand fly habitats, degrading living conditions, and weakening health systems, increasing transmission. Rising global temperatures further facilitate vector expansion into new regions, where clinical unfamiliarity often leads to misdiagnosis, delayed treatment, increased morbidity, and greater financial burden. Despite its rising incidence and global spread, CL remains a neglected tropical disease since it is seldom fatal, with scant interest by public health authorities and financial donors, limiting activities that further research and prevent spread of the disease. This review synthesizes current evidence on how geopolitical instability, forced migration, and climate-driven ecological changes collectively reshape CL epidemiology and complicate diagnosis, treatment, and surveillance. As CL extends beyond traditional geographic boundaries, it requires integrated strategies that address its multifaceted drivers through strengthened cross-border surveillance, provider education, and international coordination—focusing on prevention, diagnosis, and equitable access to diagnostics and therapeutics, especially among displaced and underserved populations. 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

This study aimed to analyze the epidemiological characteristics and incidence trends of zoonotic diseases in China from 2015 to 2022, providing evidence for zoonotic disease prevention and control strategies. Individual case data for nationally reported zoonotic diseases from the Chinese Disease Prevention and Control Information System were collected. Descriptive epidemiology and statistical methods were employed to analyze trends along with changes in their spatial, temporal, and demographic distributions. From 2015 to 2022, the annual incidence rates of leishmaniasis, Japanese encephalitis, rabies, echinococcosis, hemorrhagic fever with renal syndrome (HFRS), and schistosomiasis showed a fluctuating downward trend. The incidence rates of anthrax and leptospirosis remained relatively stable. The incidence of brucellosis declined from 2015 to 2018 but subsequently increased through 2022. Western provinces, such as Gansu, Ningxia, Qinghai, Xinjiang, and Yunnan, remain high-incidence areas for multiple zoonotic diseases, with farmers being the population at the highest risk. These findings indicate it is essential to strengthen cross-sectoral cooperation and develop region- and population-specific prevention and control strategies based on the ‘One Health’ concept, particularly in areas with high incidence rates and among high-risk populations. Full article

The northern region of Brazil is endemic for American Tegumentary Leishmaniasis (ATL) primarily caused by Leishmania guyanensis and transmitted by the sand fly Nyssomyia umbratilis. The disease occurs at different rates in the municipalities of Manacapuru (MAN) and Rio Preto da Eva (RPE), located in the state of Amazonas. Despite their geographic proximity and separation by the Rio Negro, MAN has a low incidence, whereas RPE reports a significantly higher number of cases. Since the vector is present in both locations, potential biological differences in N. umbratilis may influence transmission. Previous studies suggested genotypic and phenotypic differences in N. umbratilis from both localities. To investigate the molecular factors underlying their potentially differential vectorial capacities, we performed a comparative proteomic analysis of dissected insect intestines from both localities. Our results revealed that sand flies from MAN showed a higher abundance of proteins related to gene transcription, protein translation, amino acid and proton transport, innate immune response and intestinal motility. Since the importance of microbiota has previously been shown in parasite–vector interactions, we also identified bacteria from both vector populations. We detected bacteria specific to each population and, exclusively in MAN, some species described in the literature as having parasiticidal properties. These findings highlight molecular and microbial peculiarities that could contribute to the observed difference in ATL prevalence in the two areas. Full article

Leishmaniasis by Leishmania infantum has a zoonotic transmission cycle involving an increasing number of mammalian hosts, forming a cooperative network. The sand fly feeding on livestock is evidenced, but clinical confirmation regarding their infection is limited. We aimed to evaluate Leishmania seroprevalence in livestock to assess its impact on leishmaniasis epidemiology in an endemic area located in the Mediterranean region. A cross-sectional serological study screened livestock exposure to L. infantum and risk factors in Southern Spain. A total of 864 serum samples of clinically healthy sheep, goats, cattle, and pigs were examined by an indirect fluorescence antibody test, using a 1/80 cut-off titre to minimize cross-reactions. Global seroprevalence was 10.8%: 21.6% cattle, 15.4% sheep, 7.3% goats, and 0.6% pigs. Statistically significant differences in positive detection were observed among species (p < 0.001) and natural regions (p < 0.001). High positive reactions in cattle, goats, and sheep suggest livestock exposure to Leishmania spp. and potential asymptomatic infection. Livestock presence in biotopes could promote a dilution effect, reducing human leishmaniasis incidence. Further investigation is needed to confirm livestock roles in leishmaniasis maintenance and transmission. Full article

Background: Syphilis has recently reemerged as a significant public health concern, with rising incidence rates globally. Malignant syphilis is a rare and severe variant of secondary syphilis, often associated with immunocompromised states, particularly HIV infection. Methods: Here, we reported a rare case of malignant syphilis in a young man with well-controlled HIV. Case: A 35-year-old man with well-controlled HIV presented with disseminated ulcerated nodules and plaques, accompanied by fever, asthenia, and mild itching. Histopathology of the scapular ulcer revealed a granulomatous infiltrate. Cutaneous leishmaniasis, atypical mycobacteriosis, and T-cell lymphomas were excluded. Serological testing and polymerase chain reaction confirmed a diagnosis of malignant syphilis. Full article

Human leishmaniasis is facing important epidemiological changes in Southern Europe, driven by increased urbanization, climate changes, emerging of new animal reservoirs, shifts in human behavior and a growing population of immunocompromised and elderly individuals. In this evolving epidemiological landscape, we analyzed the clinical and epidemiological characteristics of human leishmaniasis in the Tuscany region of Central Italy. Through a multicentric retrospective analysis, we collected clinical and demographic data about all cases of leishmaniasis recorded between 2018 and 2023. We observed 176 cases of human leishmaniasis, with 128 (72.7%) visceral leishmaniasis (VL) and 47 (26.7%) cutaneous leishmaniasis (CL). Among these, 92.2% of VL and 85.1% of CL cases were autochthonous. The cumulative incidence of autochthonous human leishmaniasis was 0.22 cases per 100,000 inhabitants in 2018, but reached 1.81/100,000 in 2023. We identified three main areas of transmission: around the city of Florence (North-East Tuscany), around Grosseto city (South-West Tuscany) and Elba Island. Our findings confirm that the epidemiology of leishmaniasis is undergoing significant changes in Central Italy. Awareness towards this emerging health threat and surveillance strategies need to be improved in order to reliably assess the disease’s burden. Further research is needed in a “One-Health” perspective, to clarify the epidemiological dynamics at the environmental, reservoir, vector and human levels. The role of climate change and specific climatic factors affecting the epidemiological patterns of human leishmaniasis should be assessed. Further knowledge in these fields would promote targeted control and prevention strategies at regional and national levels. Full article

The spread of visceral leishmaniasis (VL), a serious global zoonotic parasitic disease, is mostly under control; however, several cases have been reported in recent decades in Xinjiang, China. This study aimed to analyze the epidemiological status and spatiotemporal clustering characteristics of VL in Xinjiang, China, between 2004 and 2021 to provide a basis for the development and implementation of surveillance and response measures. Data on VL incidence during 2004–2021 were collected from the National Diseases Reporting Information System of China. Global spatial autocorrelation analysis, identification of local indicators of spatial association, and spatial–temporal clustering analysis were conducted to identify the distribution and high-risk areas. A total of 2034 VL cases were reported, with a mean annual incidence of 0.50 per 100,000. There was a general decreasing trend in the incidence of VL during our study period. The majority of the cases were reported from October to February of the following year, and fewer cases were reported from April to July. Spatial autocorrelation analysis revealed that the incidence of VL was spatially clustered within a few counties. Significant differences were observed during the study period (Moran’s I = 0.74, Z = 4.900, p < 0.05). The male-to-female ratio was 1.37:1, and most patients were in the age group 0–3 years. Cases were primarily distributed in seven regions and two autonomous prefectures, and Kashgar reported the highest number of cases (1688, 82.98%). Spatial analysis revealed that the aggregation of VL was predominantly observed in southwest Xinjiang. This was in alignment with the high-risk areas identified by spatiotemporal clustering analysis. The H-H clustering region was primarily observed in Gashi, Atushi, Shufu, Injisha, Kashgar, Yepuhu, and Bachu. These findings indicate that integrated control measures must be taken in different endemic areas to strengthen the VL control program in Xinjiang, China. Full article

Cutaneous leishmaniasis (CL) is a zoonotic disease caused by protozoa of the Leishmania genus, transmitted by vectors from the Phlebotominae subfamily. The interaction between the vector, reservoir, and parasite is susceptible to climate change. This study explores how temperature and rainfall influenced the incidence of CL in 15 Colombian municipalities between 2017 and 2019. Epidemiological data were obtained from Colombia’s Instituto Nacional de Salud, while climatological data came from the Instituto de Hidrología, Meteorología y Estudios Ambientales. Using Spearman’s rank correlation coefficient, we examined the relationships between monthly climatic variables and the cumulative incidence of CL, considering various lag times. The data were further analyzed using Locally Weighted Scatterplot Smoothing (LOWESS). Our findings reveal both significant positive and negative correlations, depending on locality and climate variables. LOWESS analysis indicates that while rainfall-related incidence remains stable, temperature impacts incidence in a parabolic trend. This study underscores the significant yet complex influence of climatic factors on CL incidence. The insights gained could aid public health efforts by improving predictive models and crafting targeted interventions to mitigate the disease’s impact, particularly in regions vulnerable to climate variability. Full article

Leishmaniasis in Africa, which has been designated as a priority neglected tropical disease by various global organizations, exerts its impact on millions of individuals, primarily concentrated within this particular region of the world. As a result of the progressively grave epidemiological data, numerous governmental sectors and civil organizations have concentrated their endeavors on this widespread outbreak with the objective of devising appropriate remedies. This comprehensive examination delves into multiple facets of this parasitic ailment, scrutinizing the associated perils, diagnostic intricacies, and deficiencies within the existing therapeutic protocols. Despite the established efficacy of current treatments, they are not immune to deleterious incidents, particularly concerning toxicity and the emergence of parasitic resistance, thus accentuating the necessity of exploring alternative avenues. Consequently, this research not only encompasses conventional therapeutic approaches, but also extends its scope to encompass complementary and alternative medicinal techniques, thereby striving to identify innovative solutions. A particularly auspicious dimension of this study lies in the exploration of natural substances and by-products derived from some brown algae of the Sargassaceae family. These resources possess the potential to assume a pivotal role in the management of leishmaniasis. Full article

This study was carried out to identify the spatial distribution and characterize the clinical–epidemiological profile of Visceral Leishmaniasis (VL) in Maranhão state, Brazil, from 2009 to 2020. This descriptive ecological study collected sociodemographic and clinical data of VL cases from the Brazilian Notifiable Diseases Information System database. A spatial autocorrelation analysis (Moran statistics) was performed. From 2009 to 2020, 5699 cases of VL were reported, with incidence of 6.5 cases/100,000 and prevalence of 7.1 cases/100,000. The temporal analysis showed a significant growth in incidence from 2009 to 2018, followed by a significant decrease between 2019 and 2020. The Moran map shows hotspots of high values in the central–west and central–east regions, and hotspots of low values in the northern region of Maranhão. The profile of patients affected by VL comprises males (OR = 1.8; IC95% = 1.72–1.92), aged under 14 years, brown, and with incomplete elementary schooling. The main symptoms reported were fever, fatigue, and edema. The main diagnostic method was laboratory. The mortality rate was 6.8%, and co-infection with HIV was reported by 8.5% of patients. The results of this study indicated the increase in incidence and lethality, as well as the expansion, of leishmaniasis in the state of Maranhão. Full article

Leishmania infantum is a hemopathogen of importance for the health of domestic dogs (Canis lupus familiaris), causing canine leishmaniasis (CanL), and it is also the etiological agent of human visceral leishmaniasis (HVL). This parasite was not reported in southern Brazil until the early 2000s, but CanL and HVL were increasingly reported in the last 15 years, mainly in cities bordering Argentina. The present study aimed to detect L. infantum in domestic dogs and to determine the main clinical manifestations in infected animals from Uruguaiana, a city with a high incidence of CanL. Fifty-one dogs suspected of having CanL in the urban perimeter of the city were clinically examined by veterinarians and investigated for the occurrence of L. infantum with two immunoassays (rapid chromatography test and ELISA) and real-time PCR (polymerase chain reaction). Clinical signs were compared in positive and negative L. infantum animals. A total of 31 dogs (60.8%) were infected with L. infantum. The main clinical manifestations associated with CanL dogs were onychogryphosis and peeling (p < 0.05). L. infantum was frequently detected in urban dogs from Uruguaiana, highlighting the concerning situation regarding health in this city. The occurrence of some clinical signs (onychogryphosis/peeling) could help to detect CanL more frequently in the canine population. Full article

Background: In Brazil, human visceral leishmaniasis (HVL) is caused by the protozoan parasite Leishmania infantum, primarily transmitted by the sand fly Lutzomyia longipalpis, with dogs acting as the main urban reservoir. This study aims to evaluate the effectiveness of 4% deltamethrin-impregnated dog collars (DMC) on HVL incidence. Methods: This is a community intervention study carried out from 2012 to 2015 in the municipalities of Araguaína, State of Tocantins, and Montes Claros, State of Minas Gerais, Brazil. Two areas in each were randomly allocated to either (1) culling seropositive dogs + residual insecticide spraying (control area—CA) or (2) culling seropositive dogs + residual insecticide spraying + DMC fitted to dogs every six months for two years (intervention area—IA). Cases of HVL (n = 1202) occurring from 2008 to 2020 were identified from the Brazilian Reportable Diseases Information System and georeferenced to the control and intervention areas. The HVL cases from 2008 to 2012 were considered as occurring in the “pre-intervention” period. Those cases from 2013 to 2016 and from 2017 to 2020 were regarded as occurring in the “intervention” and “post-intervention” periods, respectively. We used a mixed-effects Poisson regression model to estimate the effectiveness of the intervention, comparing the changes from the pre-intervention period to the intervention and post-intervention periods in the control and intervention areas. Results: In Araguaína, there was a statistically significant reduction in the incidence of HVL in both the control and intervention areas, comparing both the intervention and post-intervention periods with the pre-intervention period. The intervention with DMC was significantly associated with a reduction in HVL when comparing the intervention and pre-intervention periods, yielding an effectiveness estimate of the DMC of 27% (IC95% 1–46%, p = 0.045). No differences were observed when comparing the pre- and post-intervention periods (p = 0.827). In Montes Claros, cases reduced in both the control and intervention areas from the pre-intervention period to the intervention period (p = 0.913). In the post-intervention period, the incidence increased in the control area, while cases continued to decrease in the DMC area (p = 0.188). Conclusions: The use of DMC was associated with a reduction of 27% in the incidence of HVL during the period of DMC delivery, indicating that DMC is effective as an additional strategy for controlling visceral leishmaniasis in Brazil. However, no significant reduction associated with DMC was detected after the intervention period, suggesting that a control program based on the large-scale deployment of DMC might have to be maintained for more extended periods without interruption. Full article