Memorias do Instituto Oswaldo Cruz最新文献

{"title":"Novel epitope-based diagnostic probes selected by phage display for the serological detection of HDV","authors":"Mariana Araújo Costa, Rayany Cristina de Souza, Tárcio Peixoto Roca, Adrhyan Araújo, Luiz Fellype Alves de Souza, Rutilene Barbosa Souza, Rafaela Sabatini, Bruno Silva Andrade, Iara Pereira Soares, Douglas Carvalho Caixeta, Marco Guevara-Vega, Ildercílio Mota de Souza Lima, Ana Maísa Passos-Silva, Mario Machado Martins, Abel Dib Rayashi, Daniel Archimedes da Matta, Deusilene Vieira, Luiz Ricardo Goulart, Robinson Sabino-Silva, Fabiana de Almeida Araújo Santos","doi":"10.1590/0074-02760250343","DOIUrl":"10.1590/0074-02760250343","url":null,"abstract":"<p><strong>Background: </strong>Hepatitis delta virus (HDV) is associated with the worst prognosis among viral hepatitis infections; however, it remains largely underdiagnosed, particularly in endemic developing regions, underscoring the need for new, accessible serological methods for large-scale screening.</p><p><strong>Objectives: </strong>To develop HDV-mimetic molecules using phage display for application in immunodiagnostic platforms.</p><p><strong>Methods: </strong>HDV-mimetic peptides were selected via phage display biopanning, sequenced and screened by phage-enzyme-linked immunosorbent assay (ELISA). Based on the sequences of these peptides, a recombinant protein (rHDV) was constructed and employed in an ELISA. The test was validated using 87 anti-HDV-positive samples and 93 hepatitis B virus (HBV) control samples collected from a public diagnostic laboratory in the Amazon region. Statistical analyses were performed to evaluate the diagnostic performance of the synthetic peptides and the recombinant protein.</p><p><strong>Findings: </strong>Overall, rHDV exhibits a sensitivity of 74.71%, specificity of 97.85%, and area under the curve (AUC) of 0.8906. In HDV ribonucleic acid (HDV RNA)-positive patients, diagnostic performance improved, with a sensitivity of 88.0%, specificity of 98.92%, and AUC of 0.96.</p><p><strong>Main conclusions: </strong>These findings highlight that the rHDV protein used in ELISA effectively discriminated HDV-infected individuals from patients monoinfected with hepatitis B. This demonstrates the potential of rHDV as an effective, rapid, and low-cost tool for HDV detection for broader HDV screening.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"121 ","pages":"e250343"},"PeriodicalIF":1.9,"publicationDate":"2026-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13262798/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148265306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is Wolbachia a sustainable component for dengue control?FIRST REVIEW ROUND - REVIEWERS COMMENTSREVIEWERS COMMENTS.","authors":"Narayanasamy Sivagnaname, Sivagnaname Yuvarajan, Raja Mahendran","doi":"10.1590/0074-02760250268","DOIUrl":"10.1590/0074-02760250268","url":null,"abstract":"<p><p>Wolbachia-based vector control has emerged as one of the most innovative biological interventions in contemporary dengue prevention, offering an ecologically grounded alternative to insecticide-dependent strategies. By exploiting cytoplasmic incompatibility (CI) and strain-specific viral interference, Wolbachia pipientis-transinfected Aedes aegypti (Linnaeus, 1762) mosquitoes can reduce viral transmission, as demonstrated by the Wolbachia-based field trials demonstrating proof of principle. However, the long-term sustainability of this approach remains uncertain. Accumulating field evidence indicates that Wolbachia persistence and epidemiological impact are highly context-dependent, shaped by mosquito fitness, strain-host compatibility, climatic sensitivity, urban ecology and operational continuity. Experiences from Vietnam, Thailand and parts of Brazil illustrate that stable introgression cannot be assumed and may decline when releases are interrupted or ecological conditions are unfavourable. Operational constraints - including mass-rearing quality, dispersal limitations, surveillance intensity and financial costs - pose additional scalability challenges. This perspective critically evaluates whether Wolbachia can function as a sustainable dengue control strategy across diverse endemic settings. We argue that Wolbachia should not be framed as a self-sustaining or stand-alone solution, but rather as a maintenance-dependent, context-sensitive intervention whose effectiveness relies on ecological tailoring, thermotolerant strains, robust post-release surveillance and integration within adaptive integrated vector management (IVM) frameworks. When deployed judiciously alongside complementary control measures, Wolbachia has the potential to become an important - though not exclusive - pillar of long-term dengue control.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"121 ","pages":"e250268"},"PeriodicalIF":2.5,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148150660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular epidemiology of large dengue serotypes outbreak from Peru, 2023FIRST REVIEW ROUND - REVIEWERS COMMENTSREVIEWERS COMMENTS.","authors":"Orson Mestanza, Wendy Lizarraga, Princesa Medrano, María P García, Susy Merino, Iris S Molina, Nieves Sevilla, Veronica Hurtado, Luis Barcena-Flores, Vanesa Izarra-Rojas, Karla Vásquez-Cajachahua, Alicia Nuñez-Llanos, Carlos Padilla-Rojas, Henri Bailon, Marco Galarza-Perez, Dana Figueroa, Adolfo Marcelo, Victor Jimenez-Vasquez","doi":"10.1590/0074-02760250204","DOIUrl":"10.1590/0074-02760250204","url":null,"abstract":"<p><strong>Background: </strong>Dengue has long been considered a neglected disease since its emergence. However, in recent years, the number of cases has increased significantly, particularly in tropical countries across Latin America.</p><p><strong>Objective: </strong>This study aims to describe the evolution of dengue during the 2023 outbreak in Peru.</p><p><strong>Methods: </strong>Here, we describe the analysis of 245 positive samples for dengue carried out by the National Institute of Health (INS) of Peru through genomic surveillance protocols, and analyse the evolution of serotypes and genotypes during the outbreak.</p><p><strong>Findings: </strong>We analysed 245 dengue-positive samples sequenced by the INS of Peru during the 2023 outbreak to describe the evolutionary dynamics of circulating serotypes. We identified dengue virus (DENV)-1 genotype V (lineages D.1 and D.2), DENV-2 genotype II (Cosmopolitan, lineage F.1.2), and DENV-3 genotype III (lineage B.3). Phylogenetic and population-structure analyses revealed multiple introductions, rapid diversification, and wide dispersal of DENV-1 and DENV-2 across Peru, while DENV-3III showed a localised introduction in Lima with phylogenetic links to the Caribbean. Our findings provide the most comprehensive genomic characterisation to date of dengue circulation in Peru in 2023 year, and highlight the need for sustained genomic surveillance.</p><p><strong>Main conclusion: </strong>To summarise, the three serotypes of dengue in Peru show a dynamic diversity that becomes necessary to understand, to improve public health decisions by authorities.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"121 ","pages":"e250204"},"PeriodicalIF":2.5,"publicationDate":"2026-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148150624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Five times a quarter of a century at Instituto Oswaldo Cruz.","authors":"Adeilton Alves Brandão","doi":"10.1590/0074-02760250006","DOIUrl":"10.1590/0074-02760250006","url":null,"abstract":"<p><p>The pathway of Instituto Oswaldo Cruz (IOC) runs parallel with the astonishing series of events in the 20th century, which might be viewed as a dispute between hope and ideological belief. As a centennial organisation the IOC has witnessed the same set of events and perhaps experienced some of them, but in most cases, it has been unable to influence or deter them. Since its beginnings the IOC has been engaged in addressing public health challenges and either by serendipitous findings or by the scientific inquiry it has brought some Res Novae and ignited sparks of hope that one day most of the infectious diseases that proliferate in Brazil might be controlled. In this perspective essay to introduce the series of articles in celebration of the 125th Anniversary of the IOC I will sketch an overview of its journey in the context of some 20th century events through a quarter of a century time frame.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"121 suppl 1","pages":"e250006"},"PeriodicalIF":1.9,"publicationDate":"2026-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13188972/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148042789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vitro anti-Trypanosomatid activity and chemical profile of crude extracts of Chromolaena hookeriana and Campuloclinium macrocephalum (Asteraceae)FIRST REVIEW ROUND - REVIEWERS COMMENTSREVIEWERS COMMENTS.","authors":"Ludmila Ferreira de Almeida Fiuza, Ketlym da Conceição, Krislayne Nunes, Aldana Malen Corlatti, Laura Cecilia Laurella, Simony Carvalho Mendonça, Brendo Araujo Gomes, Suzana Guimarães Leitão, Valeria Patricia Sülsen, Maria de Nazaré Correia Soeiro","doi":"10.1590/0074-02760250296","DOIUrl":"https://doi.org/10.1590/0074-02760250296","url":null,"abstract":"<p><strong>Background: </strong>Chagas disease (CD) and Leishmaniasis, caused by Trypanosoma cruzi and Leishmania species, are treated with outdated drugs that are toxic and have limited efficacy. New therapeutic alternatives are therefore needed. Natural products are valuable scaffolds for drug discovery, and Asteraceae species exhibit microbicidal activity.</p><p><strong>Objectives: </strong>This study evaluated the antiparasitic activity and selectivity of two Asteraceae species, Chromolaena hookeriana and Campuloclinium macrocephalum, against trypanosomatids.</p><p><strong>Methods: </strong>C. hookeriana and C. macrocephalum extracts were profiled by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), and their cytotoxicity and antiparasitic activity were evaluated against multiple forms and strains of T. cruzi and Leishmania amazonensis (L. amazonensis) in 2D and 3D cultures.</p><p><strong>Findings: </strong>UHPLC-MS/MS revealed predominantly pentacyclic triterpenoids in C. macrocephalum, including ursolic and oleanolic acids (negative mode) and lupeol derivatives (positive mode). C. macrocephalum was more effective than Benznidazole (Bz) (EC50 = 1.17 vs 4.47 µg/mL) against epimastigotes and nine times more potent against trypomastigotes (EC50 = 0.38 vs 3.5 µg/mL). Both extracts matched Bz activity on intracellular T. cruzi but exhibited time-dependent cytotoxicity. They also showed similar effectiveness to miltefosine (Mt) against L. amazonensis amastigotes (EC50 = 0.36-0.70 µg/mL).</p><p><strong>Main conclusions: </strong>The chemical profile supports the stronger antiparasitic activity of C. macrocephalum, likely linked to triterpenoids, and highlights Asteraceae extracts as promising candidates for drug discovery against neglected tropical diseases (NTDs).</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"121 ","pages":"e250296"},"PeriodicalIF":2.5,"publicationDate":"2026-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147973574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Memories of Memórias: shaping a century of plague research and public health policy in BrazilFIRST REVIEW ROUND - REVIEWERS COMMENTSREVIEWERS COMMENTS.","authors":"Igor Vasconcelos Rocha, Matheus Filgueira Bezerra, Marise Sobreira, Alzira Maria Paiva de Almeida","doi":"10.1590/0074-02760250269","DOIUrl":"https://doi.org/10.1590/0074-02760250269","url":null,"abstract":"<p><p>Plague, caused by Yersinia pestis, remains a historically significant and reemerging zoonotic threat worldwide. Often erroneously considered a medieval relic, the disease persists in natural foci, including Brazil, where it was introduced in 1899 via maritime trade. Over the past 125 years, the country has experienced cyclical outbreaks concentrated in the northeast, where ecological conditions support enzootic transmission among wild rodents and their fleas. While improved surveillance and control have reduced human cases in recent decades, the pathogen's zoonotic nature and potential for rapid spread in a changing climate underscore its enduring public health relevance. Memórias do Instituto Oswaldo Cruz (MIOC), one of Latin America's foremost tropical medicine journals, has been instrumental in documenting and shaping the course of plague research in Brazil. Its archives provide a unique chronological record, from pioneering studies on serum production and reservoir ecology to modern molecular analyses of bacterial virulence. This perspective synthesises the seminal contributions published in Memórias that have defined our understanding of plague in Brazil, identifies critical knowledge gaps that persist, and discusses emerging challenges in an era of climate change and shifting zoonotic disease dynamics.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"121 ","pages":"e250269"},"PeriodicalIF":2.5,"publicationDate":"2026-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147973563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vitro anti-Trypanosomatid activity and chemical profile of crude extracts of Chromolaena hookeriana and Campuloclinium macrocephalum (Asteraceae).","authors":"Ludmila Ferreira de Almeida Fiuza, Ketlym da Conceição, Krislayne Nunes, Aldana Malen Corlatti, Laura Cecilia Laurella, Simony Carvalho Mendonça, Brendo Araujo Gomes, Suzana Guimarães Leitão, Valeria Patricia Sülsen, Maria de Nazaré Correia Soeiro","doi":"10.1590/0074-02760250296","DOIUrl":"10.1590/0074-02760250296","url":null,"abstract":"<p><strong>Background: </strong>Chagas disease (CD) and Leishmaniasis, caused by Trypanosoma cruzi and Leishmania species, are treated with outdated drugs that are toxic and have limited efficacy. New therapeutic alternatives are therefore needed. Natural products are valuable scaffolds for drug discovery, and Asteraceae species exhibit microbicidal activity.</p><p><strong>Objectives: </strong>This study evaluated the antiparasitic activity and selectivity of two Asteraceae species, Chromolaena hookeriana and Campuloclinium macrocephalum, against trypanosomatids.</p><p><strong>Methods: </strong>C. hookeriana and C. macrocephalum extracts were profiled by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), and their cytotoxicity and antiparasitic activity were evaluated against multiple forms and strains of T. cruzi and Leishmania amazonensis (L. amazonensis) in 2D and 3D cultures.</p><p><strong>Findings: </strong>UHPLC-MS/MS revealed predominantly pentacyclic triterpenoids in C. macrocephalum, including ursolic and oleanolic acids (negative mode) and lupeol derivatives (positive mode). C. macrocephalum was more effective than Benznidazole (Bz) (EC50 = 1.17 vs 4.47 µg/mL) against epimastigotes and nine times more potent against trypomastigotes (EC50 = 0.38 vs 3.5 µg/mL). Both extracts matched Bz activity on intracellular T. cruzi but exhibited time-dependent cytotoxicity. They also showed similar effectiveness to miltefosine (Mt) against L. amazonensis amastigotes (EC50 = 0.36-0.70 µg/mL).</p><p><strong>Main conclusions: </strong>The chemical profile supports the stronger antiparasitic activity of C. macrocephalum, likely linked to triterpenoids, and highlights Asteraceae extracts as promising candidates for drug discovery against neglected tropical diseases (NTDs).</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"121 ","pages":"e250296"},"PeriodicalIF":1.9,"publicationDate":"2026-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13183379/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148536269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel targets and potential therapeutic approaches for chromoblastomycosis: phosphatase/peptidase inhibitors and metal-based compounds containing 1,10-phenanthrolineFIRST REVIEW ROUND - REVIEWERS COMMENTSREVIEWERS COMMENTS.","authors":"Ingrid de Souza E Sousa, Marcela Queiroz Granato, Vanila Faber Palmeira, André Luis Souza Dos Santos, Lucimar Ferreira Kneipp","doi":"10.1590/0074-02760250305","DOIUrl":"https://doi.org/10.1590/0074-02760250305","url":null,"abstract":"<p><p>Chromoblastomycosis (CBM) is a chronic, debilitating subcutaneous mycosis that remains a major therapeutic challenge due to its limited responsiveness to conventional antifungal agents. Our research group investigated key cellular mechanisms underlying fungal virulence, persistence, and resistance, revealing that CBM-associated fungi can exhibit ectophosphatase and calcineurin activities, secrete aspartic and metallo-type peptidases, and form highly structured biofilms that reinforce their chronic behaviour and tolerance to treatment. Targeted inhibition of these enzymatic systems using classical inhibitors of peptidases [e.g., human immunodeficiency virus (HIV) aspartic peptidase inhibitors], acid phosphatases (e.g., sodium orthovanadate), and calcineurin (e.g., tacrolimus and cyclosporine A) markedly impaired fungal growth, morphogenesis, biofilm development, and/or host-cell interactions, underscoring their potential roles in key fungal biological processes and infection establishment. Furthermore, coordination compounds incorporating transition metals (e.g., silver) and 1,10-phenanthroline-derived ligands demonstrated potent antifungal efficacy against CBM-associated fungi and may interfere with key physiological and virulence-associated pathways. Collectively, these findings advance the understanding of CBM fungal pathophysiology, unveiling novel molecular targets and highlighting opportunities for alternative therapeutic strategies and antifungal drug development.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"121 suppl 1","pages":"e250305"},"PeriodicalIF":2.5,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147973580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unseen, untreated: chronic Giardia lamblia infections and the gaps in health systemsFIRST REVIEW ROUND - REVIEWERS COMMENTSREVIEWERS COMMENTS.","authors":"Deiviane Aparecida Calegar, Filipe Anibal Carvalho-Costa, Alda Maria Da-Cruz, Maria Fantinatti","doi":"10.1590/0074-02760250251","DOIUrl":"https://doi.org/10.1590/0074-02760250251","url":null,"abstract":"<p><p>Giardiasis is a chronic disease that impairs intestinal absorption and, independently of diarrhoea, contributes to growth and developmental delays, making it an important risk factor for protein-energy malnutrition in children. Its high prevalence is associated with poor sanitation and multiple faecal-oral transmission routes, including person-to-person spread, contamination of water and food, and zoonotic cycles. Giardia lamblia closely interacts with the intestinal epithelium, triggering inflammatory and immune responses. Despite its impact, giardiasis is underdiagnosed, and there is an urgent need for microscopy-independent diagnostic tools suitable for large-scale use. Treatment options include metronidazole or single-dose regimens such as secnidazole and tinidazole, which are more effective but not yet implemented at the community level. Because exposure is continuous, reinfections are frequent, making sustained control particularly challenging. Control efforts could be strengthened through primary health care by expanding access to diagnosis and providing large-scale single-dose treatments, especially in vulnerable communities with poor sanitation. Giardiasis therefore remains an invisible and untreated disease, despite affecting millions and impairing childhood development.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"121 suppl 1","pages":"e250251"},"PeriodicalIF":2.5,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147973536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of a new rapid diagnostic test, based on the chimeric protein Q5, for the diagnosis of human and canine forms of visceral leishmaniasis.","authors":"Wagner José Tenório Dos Santos, Natalia Rocha Nadaes, Allana Kelly Oliveira Dutra, Adalucia da Silva, Hemilly Rayanne Ferreira da Silva, Artur Leonel de Castro Neto, Virgínia Maria Barros de Lorena, Valeria Rêgo Alves Pereira, Allana Maria de Souza Pereira, Maria Edileuza Felinto de Brito, Milena de Paiva Cavalcanti, Zulma Maria Medeiros, Kamily Fagundes Pussi, Herintha Coeto Neitzke-Abreu, Valeria Marçal Felix de Lima, Carlos Henrique Nery Costa, Keila Gisele Azevedo F Dos Santos, Edimilson Domingos da Silva, Osvaldo Pompilio de Melo Neto","doi":"10.1590/0074-02760250126","DOIUrl":"10.1590/0074-02760250126","url":null,"abstract":"<p><strong>Background: </strong>Visceral leishmaniasis (VL), caused by Leishmania infantum, is the most severe form of leishmaniasis, prevalent in many countries, but still with limitations in diagnosis for both human and canine hosts. Serological assays based on recombinant proteins are the most efficient diagnostic alternatives, with the rapid diagnostic test (RDT) being the most cost-effective. The previously described chimeric Q5 is a recombinant protein derived from three native L. infantum antigens, which is potentially useful for both human and canine VL diagnosis, through preliminary enzyme-linked immunosorbent assay (ELISA), but which was not evaluated within an RDT setting.</p><p><strong>Objectives: </strong>To evaluate the diagnostic performance of the chimeric recombinant protein Q5 in both ELISA and RDT formats for the detection of human and canine VL, and to compare its performance with RDTs based on Lci2 and Lci13 antigens.</p><p><strong>Methods: </strong>Here, we first expanded the Q5 evaluation through ELISA with a larger set of human and canine VL-positive sera from multiple origins. We confirmed a sensitivity ranging between 80% and 90% for the human VL and greater than 90% with the canine VL sera. A new RDT-Q5 was then set up and tested with multiple batches of human and canine sera.</p><p><strong>Findings: </strong>An improved performance was seen for the human VL diagnosis (94% sensitivity), but it was reduced with canine sera (86% sensitivity). Specificity values for both the ELISA-Q5 and RDT-Q5 were generally greater than 95%, with limited (8%) or no false-positive results with human sera from individuals with cutaneous leishmaniasis (CL) and Chagas disease (CD), respectively. The RDT-Q5 performance was compared with RDTs based on two other recombinant proteins, Lci2 and Lci13, tested respectively for the human and canine VL diagnosis.</p><p><strong>Main conclusions: </strong>Despite an equivalent performance for the human VL diagnosis, the RDT-Lci2 led to a much greater incidence of false-positive results with the CL and CD sera. In contrast, no setup for the RDT-Lci13 was effective with the canine sera. Our results confirm the RDT-Q5 as an efficient alternative for the VL diagnosis in the field, particularly for the human form of the disease.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"121 ","pages":"e250126"},"PeriodicalIF":1.9,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13182565/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148042776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}