Acta tropica最新文献

{"title":"Molecular evidence of Mycobacterium avium subspecies paratuberculosis (MAP) shedding in the invasive American mink (Neogale vison) in southern Chile","authors":"Carlos Tejeda ,&nbsp;Natalia Pérez ,&nbsp;Francisca Escobar ,&nbsp;Daniel Iturra ,&nbsp;Brandon Aristizábal ,&nbsp;Eduardo Raffo ,&nbsp;Manuel Moroni ,&nbsp;Miguel Salgado ,&nbsp;Felipe A. Hernández","doi":"10.1016/j.actatropica.2026.107991","DOIUrl":"10.1016/j.actatropica.2026.107991","url":null,"abstract":"<div><div><em>Mycobacterium avium</em> subsp. <em>paratuberculosis</em> (MAP) is the causative agent of Johne’s disease (paratuberculosis), a chronic enteritis affecting domestic and wild ruminants worldwide. While MAP transmission primarily occurs among livestock, increasing attention has been given to the role of wildlife in the maintenance and spread of this pathogen. Invasive species, such as the American mink (<em>Neogale vison</em>), may serve as unexpected source of infection or mechanical vectors for MAP, especially in regions where wildlife and domestic animals share habitats. In this study, we performed a specific MAP-IS<em>900</em> real-time PCR assay to detect bacterial DNA in mesenteric lymph nodes (MesLN) (<em>n</em> = 401) and colonic/rectal fecal swabs (<em>n</em> = 346) from minks in Los Ríos region, Chile. We detected MAP DNA in 16 % and 10 % of minks in MesLN and fecal swabs, respectively, while 4 % of minks were MAP qPCR-positive in both MesLN and fecal swab samples. Considering specimens with known sex and age, we detected MAP DNA in 22 % of minks in either MesLN or fecal swabs, where 21 % of males and 22 % of females were MAP qPCR-positives, and 15 % of juveniles, 25 % of subadults, and 21 % of adults were MAP DNA-positive in at least one sample type. Our study is the first report on MAP detection in this non-ruminant carnivore in Chile, raising further questions about interspecies transmission dynamics and the potential environmental dissemination of this bacterial agent. These findings highlight the need for broader surveillance strategies that incorporate wildlife, particularly invasive species, into MAP control programs.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"275 ","pages":"Article 107991"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146049509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cognitive sequelae associated with parenchymal and extraparenchymal neurocysticercosis","authors":"Rebeca Ramírez-Bustamante ,&nbsp;Ana Ruth Diaz-Victoria ,&nbsp;Agnès Fleury","doi":"10.1016/j.actatropica.2026.108009","DOIUrl":"10.1016/j.actatropica.2026.108009","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Background&lt;/h3&gt;&lt;div&gt;While the incidence of neurocysticercosis (NC) with viable parasites has been declining in Mexico and some other countries, this trend is not observed globally, and the burden of patients who have previously suffered from NC remains considerable. Cognitive manifestations are often overlooked in the clinical management of NC. In routine practice, patients are generally considered cured once viable parasites are no longer detectable, despite the potential for persistent neurological sequelae.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Objectives&lt;/h3&gt;&lt;div&gt;To evaluate the frequency, characteristics, and severity of cognitive sequelae in patients with a history of NC.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Methods&lt;/h3&gt;&lt;div&gt;We conducted a cross-sectional, descriptive study at the National Institute of Neurology and Neurosurgery in Mexico City, between 2022 and 2024, involving 105 patients with a history of neurocysticercosis who had no viable parasites at the time of inclusion. Patients were categorized into three groups: parenchymal NC with a single calcification, parenchymal NC with multiple calcifications, and healed extraparenchymal NC who, at the time of NC diagnosis, had intracranial hypertension requiring ventriculoperitoneal shunt placement. Cognitive function was assessed using the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA). Results were compared to those from a healthy control group, matched with patients by age, sex and educational level.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;The results highlight a significant cognitive impairment in patients with a history of NC compared to controls: MMSE: 22 (&lt;span&gt;&lt;span&gt;Boppré et al., 2001&lt;/span&gt;&lt;/span&gt;- (&lt;span&gt;&lt;span&gt;Tseng et al., 2024&lt;/span&gt;&lt;/span&gt;) vs. 26 (&lt;span&gt;&lt;span&gt;Tseng et al., 2024&lt;/span&gt;&lt;/span&gt;- (&lt;span&gt;&lt;span&gt;Helmstaedter and Witt, 2017&lt;/span&gt;&lt;/span&gt;), &lt;em&gt;p&lt;/em&gt; &lt; 0.0001; MoCA: 20 (&lt;span&gt;&lt;span&gt;Tombaugh and McIntyre, 1992&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Aguilar-Navarro et al., 2018&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Cervigni et al., 2022&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Del Brutto et al., 2019&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Boppré et al., 2001&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Rodrigues et al., 2012&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Rabearisoa et al., 2024&lt;/span&gt;&lt;/span&gt;) vs. 25 (&lt;span&gt;&lt;span&gt;Rabearisoa et al., 2024&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Hamamoto Filho et al., 2019&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Tseng et al., 2024&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Koivisto et al., 2013&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Xiao et al., 2022&lt;/span&gt;&lt;/span&gt;; &lt;span&gt;&lt;span&gt;Helmstaedter and Witt, 2017&lt;/span&gt;&lt;/span&gt;), &lt;em&gt;p&lt;/em&gt; &lt; 0.0001. When comparing the three groups of patients, MMSE results showed a higher frequency of dementia in the patients with history of extraparenchmal NC (18 %) compared to the patients with history of parenchymal NC (0 %), p=0.001, while frequency of mild cognitive impairment was higher in the parenchymal group (78 %) vs. extraparenchymal grup (47.3 %), p=0.003. Notably, cognitive function was not influenced by the pr","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"275 ","pages":"Article 108009"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146117070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New targeted next-generation sequencing (NGS) panel for detection of acute respiratory infection pathogens","authors":"Maksim Koryukov ,&nbsp;Andrey Kechin ,&nbsp;Mariya Gordukova ,&nbsp;Darya Shamovskaya ,&nbsp;Svetlana Akalovich ,&nbsp;Alexander Rymko ,&nbsp;Maksim Filipenko","doi":"10.1016/j.actatropica.2026.108008","DOIUrl":"10.1016/j.actatropica.2026.108008","url":null,"abstract":"<div><div>Respiratory infections are among the leading causes of morbidity and mortality worldwide, especially among children, the elderly, and immunocompromised individuals. To address the limitations of the existing diagnostic tools and improve testing efficiency, we developed, optimized and tested in-house targeted next-generation sequencing assay capable of simultaneously detecting 32 groups of viruses and 13 bacteria commonly associated with respiratory infections. Using NGS-PrimerPlex, we designed a total of 117 primer pairs—at least two per pathogen—targeting different genomic regions. These primers were divided into three multiplex PCR reactions and evaluated both <em>in silico</em> for specificity and coverage, and <em>in vitro</em> via monoplex PCR with positive controls and polyacrylamide gel electrophoresis. We systematically optimized key variables including primer (15–260 nM) and dNTP (0.1–1.6 mM) concentrations, PCR cycle number (20–35), annealing temperature (57–62°C), ramp rate (0.2–4°C/s), and reverse transcription protocols. The assay was validated using 120 complementary DNA (cDNA) samples from patients at Speransky Children’s Hospital #9 in Moscow, Russia, previously tested with a commercial multiplex PCR respiratory virus panel. The NGS assay showed complete concordance with the PCR results in 60% of positive samples, increasing to 74% when samples with Cq values above 29 were excluded. Additionally, the NGS assay detected target pathogens in 13 PCR-negative samples and identified other respiratory pathogens not included in the commercial panel in 47 PCR-negative samples. Overall, the assay identified at least one target pathogen in 86 of 120 samples, demonstrating its potential for comprehensive respiratory pathogen detection, surveillance, and clinical diagnostics. Our findings offer a robust foundation for future development of targeted NGS-based assays.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"275 ","pages":"Article 108008"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146117057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal stress responses on developmental time, survival, and wing morphometrics in desert and coastal strains of Aedes aegypti (Diptera: Culicidae) from India","authors":"Sushmita Swain ,&nbsp;Gaurav Sharma ,&nbsp;Rakesh Kumar Samantaray ,&nbsp;Devi Shankar Suman","doi":"10.1016/j.actatropica.2026.107994","DOIUrl":"10.1016/j.actatropica.2026.107994","url":null,"abstract":"<div><h3>Background</h3><div><em>Aedes aegypti</em> is a primary vector of dengue, chikungunya, Zika, and yellow fever diseases. Despite its global invasion, little is known about how populations from climatically contrasting regions adapt to varied thermal environments. Understanding survival strategies is critical for predicting population dynamics and disease transmission under climate change. To address this gap, we assessed ecological adaptations in terms of development, survival, and wing length, along with molecular variations, in the Thar Desert (Jodhpur) and the east coastal (Kolkata) strains of <em>Ae. aegypti</em>.</div></div><div><h3>Methods</h3><div>Mosquito eggs (3rd generation) of the coastal and desert <em>Ae. aegypti</em> strains were subjected to 20, 26, 30, and 35 °C to assess the impact on developmental time, survival rate, and wing length. The mitochondrial COI gene was analysed to examine nucleotide sequence variation and protein physicochemical properties.</div></div><div><h3>Results</h3><div>The desert strain developed faster, but showed inferior survival compared to the coastal strain at all temperatures tested. Temperature also affected wing length in both strains, showing significant differences between strains at 35 °C for males and at 30 °C for females. Wing length of the desert strain was less impacted by temperature increase (30 to 35 °C) compared to the coastal strain for both males and females. The COI gene formed two distinct clades. Three transition nucleotide mutations (Adenosine with Guanosine) altered physicochemical and structural properties of the COI protein (<em>i.e.</em>, molecular weight, theoretical isoelectric point, total number of positively charged residues, and the number of atoms). Additionally, the bad angles, instability index, and GRAVY affected the protein.</div></div><div><h3>Conclusion</h3><div>This study provides a comparative analysis linking life-history traits with genetic variation in <em>Aedes aegypti</em> mosquitoes from climatically distinct regions of India. Temperature affects the survival, developmental rates, and wing length of genetically varied <em>Ae. aegypti</em> from different ecological areas. This may refine the understanding of population dynamics and management.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"275 ","pages":"Article 107994"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146117093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tick mitogenomes: Structural characteristics, phylogenetic implications, and a critical synthesis from sequencing to systematics","authors":"Mourad Ben Said ,&nbsp;Myriam Kratou ,&nbsp;Hanène Belkahia","doi":"10.1016/j.actatropica.2026.108015","DOIUrl":"10.1016/j.actatropica.2026.108015","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Ticks (Acari: Ixodida) are obligate hematophagous ectoparasites that play a pivotal role in transmitting a wide array of pathogens to humans and animals. However, their traditional morphology‐based identification has long been challenged by subtle interspecific differences and intraspecific variability, particularly among soft ticks (Argasidae), which has resulted in conflicting taxonomic arrangements. In recent years, complete mitochondrial genomes (mitogenomes) have emerged as a powerful and informative tool, providing a rich, maternally inherited marker set comprising 13 protein‐coding genes, 22 tRNAs, and two rRNAs. These genomic features make mitogenomes ideally suited for resolving both deep and recent divergences across tick lineages. The advent and widespread adoption of high‐throughput sequencing platforms (e.g., Illumina and Oxford Nanopore), together with specialized bioinformatic pipelines such as SPAdes, MitoZ, MITOS, and ARWEN, have now revolutionized the field by enabling the routine recovery of full mitogenomes from both fresh and archival specimens. This technological progress has effectively overcome earlier challenges associated with DNA degradation and repetitive control regions. Furthermore, comparative annotation workflows that integrate automated gene prediction with careful manual curation now ensure accurate gene‐order mapping and precise delineation of tRNA boundaries. As a result, phylogenomic analyses based on concatenated mitochondrial protein‐coding genes and rRNAs robustly support the monophyly of major tick families such as Argasidae, Ixodidae, and Nuttalliellidae and clarify evolutionary relationships within several medically important genera, including &lt;em&gt;Ixodes, Rhipicephalus, Amblyomma, Dermacentor, Hyalomma&lt;/em&gt; and &lt;em&gt;Haemaphysalis.&lt;/em&gt; Nevertheless, an overreliance on mitochondrial DNA alone carries inherent risks, including potential misinterpretation of hybrid taxa, incomplete lineage sorting, and maternal introgression. To address these limitations, integrative phylogenomic frameworks that combine mitochondrial and nuclear datasets such as 18S-28S rRNA, ITS2, and ultraconserved elements are essential for reconciling conflicting evolutionary signals and achieving robust species delimitations. Despite these advances, several critical gaps remain, including the under‐sampling of African and Southeast Asian tick lineages, limited integration of nuclear genomic data, and an incomplete understanding of the functional roles of control‐region duplications and tick‐box motifs. Thus, this review aims to address current challenges in tick mitochondrial genomics by outlining best‐practice guidelines that ensure accuracy, reproducibility, and data integrity. These include dual‐platform sequencing for assembly validation, standardized quality‐control reporting (e.g., DNA Integrity Numbers and per‐gene coverage), partitioned model testing in phylogenetics, rigorous morphological verification, and open shari","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"275 ","pages":"Article 108015"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146148699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Water physicochemical parameters linked to mosquito diversity and arbovirus infection in Mexico City","authors":"Stephany Rodríguez-González ,&nbsp;Manuel Edday Farfán-Beltrán ,&nbsp;Jorge Cime-Castillo ,&nbsp;Humberto Lanz-Mendoza ,&nbsp;Herón Huerta ,&nbsp;Alex Córdoba-Aguilar","doi":"10.1016/j.actatropica.2026.108016","DOIUrl":"10.1016/j.actatropica.2026.108016","url":null,"abstract":"<div><div>Urban landscapes can shape mosquito community composition and influence arbovirus transmission dynamics. The rapid urbanization and environmental heterogeneity of Mexico City have created diverse aquatic microhabitats that may favor specific mosquito assemblages. Therefore, we surveyed mosquito communities and their aquatic environmental conditions across eight regions of the city between May 2023 and April 2024. 2,569 adult female mosquitoes were collected using CDC light traps, oral aspirators, and dippers for immature stages. Physicochemical parameters were simultaneously recorded at breeding sites specifically from May 2023 to November 2023. Redundancy analysis revealed that temperature and conductivity were associated with species distribution. To complement the ecological assessment, we screened the collected females for dengue, Zika, and chikungunya yet no arboviral RNA was detected. Our results depict how mosquito communities can be shaped by physicochemical variables, similar to other related studies. That no arboviruses were detected does not mean that Mexico City is free from this threat given the reports of this in close, neighboring cities. Thus, a surveillance program is needed to prevent arboviral emergence.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"275 ","pages":"Article 108016"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146197345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ellipsomyxa (Cnidaria: Myxozoa): diversity, life history, and description of new species from the Amazon Basin","authors":"Rayline T.A. Figueredo ,&nbsp;Maria I. Müller ,&nbsp;Lincoln L. Corrêa ,&nbsp;Beth Okamura ,&nbsp;Paul F. Long ,&nbsp;Edson A. Adriano","doi":"10.1016/j.actatropica.2026.108004","DOIUrl":"10.1016/j.actatropica.2026.108004","url":null,"abstract":"<div><div>Myxozoans belonging to the genus <em>Ellipsomyxa</em> have been described in the gallbladders of fish from marine, brackish, and freshwater environments worldwide. Recent research suggests substantial speciation in South America freshwater environments. This study enhances our understanding of the diversity of freshwater <em>Ellipsomyxa</em> in the Amazon Basin, with the description of two new species. It also provides novel life history insights, expands host ranges, and proposes taxonomic revision. <em>Ellipsomyxa filiformis</em> n. sp. was identified infecting the gallbladder of the pimelodid Amazonian fish <em>Hypophthalmus marginatus. Ellipsomyxa granulosa</em> n. sp. was found in the gallbladder of the curimatid <em>Curimata inornata. Ellipsomyxa amazonensis</em> is here reported to parasitise two pimelodids - <em>Pinirampus pirinampu</em> and Platynematichthys notatus. <em>Ellipsomyxa paraensis</em> is reported to parasitize the cichlid <em>Satanoperca jurupari</em> and the prochilodontid <em>Prochilodus nigricans.</em> Morphological and small subunit ribosomal DNA sequence data support the reclassification of <em>Ellipsomyxa santarenensis</em> as a junior synonym of <em>E. paraensis.</em> Molecular phylogenetic analyses indicate that <em>E. filiformis</em> n. sp. and <em>E. granulosa</em> n. sp. comprise a sister lineage to <em>Ellipsomyxa papantla</em>. Ultrastrucutural analyses of <em>E. filiformis</em> n. sp. and <em>E. granulosa</em> n. sp. revealed details of the plasmodia, including numerous filopodial and pseudopodial projections of the ectoplasm, and a concentration of actin associated with the cytoskeleton.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"275 ","pages":"Article 108004"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146096748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Host kynurenine monooxygenase (KMO) serves as a critical immune defense factor restricting Toxoplasma gondii proliferation","authors":"Sheng-Jie Tang ,&nbsp;Zhong-Yang Chen ,&nbsp;Ya-Fei Song ,&nbsp;Yanlong Gu ,&nbsp;Yanmin You ,&nbsp;Dong-Hui Zhou","doi":"10.1016/j.actatropica.2026.108012","DOIUrl":"10.1016/j.actatropica.2026.108012","url":null,"abstract":"<div><div><em>Toxoplasma gondii</em> is an obligate intracellular protozoan parasite capable of infecting virtually all warm-blooded animals. The kynurenine pathway (KP), a key route of tryptophan catabolism, serves as a critical immunometabolic checkpoint in cancer, autoimmune disorders, and neurodegenerative diseases. Although the kynurenine monooxygenase (KMO)-derived metabolite quinolinic acid (QUIN) has well-documented antiviral effects, its role in antiparasitic immunity remains unexplored. Here, we identify KMO as a critical mediator of host defense against <em>T. gondii</em>. Upon infection, <em>T. gondii</em> significantly suppresses host KMO expression along with its downstream metabolites, including 3-hydroxykynurenine (3-HK) and QUIN. Functional studies in Vero cells demonstrate that KMO overexpression effectively restricts parasite proliferation, whereas RNA interference (RNAi)-mediated knockdown (KD) of KMO increases parasite burden. Collectively, these findings establish KMO as a non-canonical determinant of anti-<em>T. gondii</em> immunity and nominate KP potentiation as a therapeutic strategy for toxoplasmosis.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"275 ","pages":"Article 108012"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146140692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A qPCR-based strategy for differential diagnosis of visceral and cutaneous leishmaniasis in humans and dogs","authors":"José Bryan Rihs ,&nbsp;Mariana Teixeira Vilela ,&nbsp;Janete Soares Coelho dos Santos ,&nbsp;Antero Silva Ribeiro de Andrade ,&nbsp;Job Alves de Souza Filho ,&nbsp;Marcos Paulo Gomes Mol ,&nbsp;Sérgio Caldas ,&nbsp;Rodrigo Souza Leite","doi":"10.1016/j.actatropica.2026.107999","DOIUrl":"10.1016/j.actatropica.2026.107999","url":null,"abstract":"<div><div>This study developed a quantitative real-time PCR (qPCR)-based strategy for the differential molecular diagnosis of visceral and cutaneous leishmaniasis in humans and dogs, using blood, skin biopsy, and conjunctival swab samples. The assay demonstrated satisfactory sensitivity and specificity, reaching 93.3% and 100% in human samples and 90.48% and 100% in canine samples, across the evaluated species (<em>Leishmania infantum, L. braziliensis</em>, and <em>L. amazonensis</em>). Detection of <em>L. amazonensis</em> required an adapted protocol incorporating SYTO9 intercalating dye and melting curve analysis. Although exploratory, these results indicate that the proposed method is feasible and support its potential for further validation in larger cohorts and future studies.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"275 ","pages":"Article 107999"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146083785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of novel orthonairovirus and unclassified flavivirus in Rhipicephalus appendiculatus ticks in Kenya","authors":"Lydia Mali Langata ,&nbsp;Joel Lutomiah ,&nbsp;Elizabeth Ajema Chebichi Luvai ,&nbsp;Shelly Wulandari ,&nbsp;Marla Anggita ,&nbsp;Weiyin Hu ,&nbsp;Kazuki Kiuno ,&nbsp;Miyuka Nishizato ,&nbsp;Gabriel Aboge ,&nbsp;Peter Kimeli ,&nbsp;Yohei Kurosaki ,&nbsp;Ai Takano ,&nbsp;Hiroshi Shimoda ,&nbsp;Shingo Inoue ,&nbsp;Daisuke Hayasaka","doi":"10.1016/j.actatropica.2026.108014","DOIUrl":"10.1016/j.actatropica.2026.108014","url":null,"abstract":"<div><div>Tick-borne viruses (TBVs) include the highly pathogenic viruses associated with infectious diseases in both humans and animals. The global public health concern of TBVs is closely related to geographic distribution of ticks. In Africa, a variety of TBVs have been reported by detections from ticks and high seroprevalence in humans and domestic animals. In this study, we aimed to detect TBVs from ticks in Kenya by targeting viral genes of <em>Orthoflavivirus, Bandavirus</em> and <em>Orthonairovirus</em>. Ticks were collected from cattle, camels, sheep and goats in Isiolo, Narok and Baringo counties, and viral RNA detections were attempted by RT-PCR. There were no positive samples for <em>Orthoflavivirus</em> and <em>Bandavirus</em>. On the other hand, 10 samples tested positive for Orthonairovirus by RT-PCR, were identified from <em>Rhipicephalus appendiculatus</em> tick pools. Five pools were indicated as novel <em>Orthonairovirus</em> species, marigat tick orthonairovirus (MTOV). Interestingly, other 5 samples were considered to be Bole tick virus 4 (BLTV4) and BLTV4-related virus, marigat tick flavivirus (MTFV), belonging to unclassified genus within family <em>Flaviviridae,</em> but not <em>Orthonairovirus</em>. Our findings add to the knowledge of genetic diversity and geographic distribution of tick-borne viruses including novel <em>Orthonairovirus</em> MTOV, unclassified <em>Flavivirus</em> BLTV4 and MTFV in Kenya, and will provide useful clues for further epidemiological surveys.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"275 ","pages":"Article 108014"},"PeriodicalIF":2.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146177174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}