Memorias do Instituto Oswaldo Cruz最新文献

{"title":"Role of the epitranscriptome in viral infections: beneficial or detrimental?","authors":"Muhammad Fawwaz Abdullah, Kok Sing Yee, Nurhafiza Zainal, Sazaly AbuBakar, Chin Kim Ling","doi":"10.1590/0074-02760250055","DOIUrl":"10.1590/0074-02760250055","url":null,"abstract":"<p><p>Epitranscriptomics, the study of post-transcriptional chemical base modifications of RNAs, has become a crucial area of research for understanding the complex interactions between viruses and their hosts. These RNA modifications significantly impact both viral and host RNA functions, influencing viral replication, transcription, translation, and immune evasion. The advancement of high-throughput technologies, such as mass spectrometry-based techniques and next-generation sequencing, has enabled researchers to investigate epitranscriptomic modifications and their roles in gene regulation in greater depth. Viral RNAs often carry various epitranscriptomic modifications that facilitate their stability and translation, enabling viruses to hijack the host environment, enhance replication, and evade immune defences. Conversely, host epitranscriptomic modifications can enhance antiviral responses by regulating gene expression and promoting the degradation of viral RNAs. This dual role underscores the complexity of virus-host dynamics, where epitranscriptomic modifications can be both beneficial and detrimental. This review aims to provide an overview of current knowledge on epitranscriptomic modifications in viral infections, focusing on their roles in viral replication and immune interactions, while considering their potential as targets for antiviral therapeutic intervention.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e250055"},"PeriodicalIF":2.5,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12494403/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145251844","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":"The impact of probiotic administration in vivo on peritoneal mouse macrophages infected by Leishmania amazonensis ex vivo.","authors":"Lauren Van den Broeck, Raquel Silva de Azevedo, Ludmila Ferreira de Almeida Fiuza, Marcos Meuser Batista, Cynthia Machado Cascabulho, Ewout Van de Velde, Serge Van Calenbergh, Guy Caljon, Maria de Nazaré Correia Soeiro","doi":"10.1590/0074-02760250014","DOIUrl":"10.1590/0074-02760250014","url":null,"abstract":"<p><strong>Background: </strong>The microbiome is fundamental in the host's immunobiology and dysbiosis leads to pathological conditions, potentially affecting parasitic diseases.</p><p><strong>Objectives: </strong>To investigate how oral probiotics affect infection and antiparasitic treatment of Leishmania in macrophages.</p><p><strong>Methods: </strong>Swiss mice were orally treated with 109 colony forming units (CFU) multi- or single-strain probiotic formulations (PB8, Bifilac), their peritoneal mouse macrophages (PMMs) were obtained and infected ex vivo with L. amazonensis amastigotes. The effects of prior probiotic administration on ex vivo infection and treatment responses to 1 µM miltefosine and N 6-methyltubercidin were evaluated. Flow cytometry measured the inflammatory mediator release in the supernatant of the PMMs.</p><p><strong>Findings and main conclusions: </strong>PB8 or Bifilac administration significantly reduced (p < 0.05) ex vivo infection of PMMs from male mice by 27% and 12%, respectively. No gender-dependent effect of probiotics was observed. No improved antiparasitic activity of 1 µM miltefosine or N 6-methyltubercidin was observed in probiotic-treated PMMs. Ex vivo Leishmania infection stimulated tumour necrosis factor (TNF), MCP-1, and interleukin-6 (IL-6) production by PMMs (p < 0.05). A trend of increase was recorded with elevated levels of TNF and IL-6 in PB8-treated male groups (around 43 and 52%, respectively) but were not statistically significant. Collectively, probiotic treatment of mice influences Leishmania infection in PMMs. Clinical applications in leishmaniasis warrant further studies.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e250014"},"PeriodicalIF":2.5,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12456958/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145131208","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":"Phospholipids and phospholipase A1 as antigens during the course of experimental Trypanosoma cruzi infection.","authors":"Emanuel Bott, Sebastián Andrés López, Guadalupe Gimenez, María Elisa Solana, María Laura Belaunzarán","doi":"10.1590/0074-02760240281","DOIUrl":"10.1590/0074-02760240281","url":null,"abstract":"<p><strong>Background: </strong>Trypanosoma cruzi, causative agent of Chagas disease (CD), remains a public health problem in Latin America and is emerging in non-endemic areas. Phospholipids (PL) are essential components of biomembranes and their enzymatic modification by phospholipases yields bioactive lipids that modulate immune responses. Anti-PL antibodies have been associated with autoimmune diseases and inflammation, potentially influencing CD pathology by recognising PL and PL-binding proteins. T. cruzi Phospholipase A1 (TcPLA1) hydrolyses membrane PL and participates in parasite-host cell interactions.</p><p><strong>Objectives: </strong>This study evaluated IgM and IgG antibody responses against phosphatidylcholine, phosphatidylethanolamine, and their derived lysophospholipids (LPL), as well as recombinant TcPLA1, during experimental T. cruzi infection with two strains: RA (high virulence) and K98 (low virulence). It also aimed to predict the recognition capacity of TcPLA1 by CD patients using in silico analysis.</p><p><strong>Methods: </strong>Antibody responses were analysed by enzyme-linked immunosorbent assay (ELISA) using different PL and recombinant TcPLA1 as antigens. Lytic activity assays were performed to evaluate the functional impact of anti-PL antibodies. The CHAGASTOPE resource was used to predict TcPLA1 antigenicity.</p><p><strong>Findings: </strong>This study identified IgM and IgG antibodies against PL, LPL and TcPLA1 during experimental T. cruzi infection. Different amino acid sequences of TcPLA1 showed stronger antigenic recognition by CD patient's sera.</p><p><strong>Main conclusions: </strong>The presence of these antibodies suggests their involvement in the pathogenesis of CD and their potential as markers for disease monitoring and prognosis.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240281"},"PeriodicalIF":2.5,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12440295/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145075546","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":"Concomitant use of anti-leishmanial therapy and antibacterial prophylaxis reduces plasma LPS levels and improves several aspects of experimental Leishmania infantum infection in golden hamsters.","authors":"Joanna Reis Santos-Oliveira, Maria Luciana Silva-Freitas, Marcelle da Senhora Cappato, Elaine Marques-Paulo, Milla Bezerra Paiva, Sandra Regina Soares, Dayane Alvarinho de Oliveira, Eduardo José Lopes-Torres, Marcelo Pelajo-Machado, Eduardo Fonseca Pinto, Jose Angelo L Lindoso, Hiro Goto, Alda M Da-Cruz","doi":"10.1590/0074-02760240266","DOIUrl":"10.1590/0074-02760240266","url":null,"abstract":"<p><strong>Background: </strong>Parasite antigens and plasma lipopolysaccharide (LPS) levels from luminal origin in visceral leishmaniasis (VL) patients are correlated with cellular activation and low CD4+T cell counts.</p><p><strong>Objectives: </strong>Our aim was to verify whether Leishmania infantum infection damages the intestinal barrier and whether combination antimonial/antibiotic contributes to the reduction of LPS levels and immune activation.</p><p><strong>Methods: </strong>Golden hamsters were grouped in: G1-uninfected; G2-infected with L. infantum; and G3/G4 and G5-infected, treated with antimonial, antibiotic or both drugs, respectively. The treatment initiated 45 days post infection (dpi), daily by 10 days.</p><p><strong>Findings: </strong>G2, G3, and G4 animals showed a significant increase in spleen weight compared to G1. An elevated parasite load was observed in G2, unlike the G3, G4, and especially, G5, whose decrease was significant at 120 dpi. Intestinal mucosal alterations and elevated LPS levels were observed in G2 group. However, G3, G4 and G5 animals showed lower LPS levels than G2. Moreover, G4 and G5 presented higher CD4+T-cell percentages and lower activation levels than G2 and G3, either at 60 or 101-120 dpi.</p><p><strong>Main conclusions: </strong>Our results showed evidence of bacterial translocation in experimental VL and that the concomitant use of antimonial and antibiotic may reduce LPS levels, along with an improvement of the immunosuppression and reduction of lymphocyte activation.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240266"},"PeriodicalIF":2.5,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12418786/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145033682","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":"Opening the conversation in peer review, finally.","authors":"Adeilton Alves Brandão, Ana Carolina P Vicente","doi":"10.1590/0074-02760250005","DOIUrl":"10.1590/0074-02760250005","url":null,"abstract":"","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e250005"},"PeriodicalIF":2.5,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12419696/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145033709","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":"Beyond the first case of Chagas disease: the Berenice strain as a model for understanding long-term Trypanosoma cruzi infection.","authors":"Diana Bahia, André Guilherme da Costa-Martins, Werica Bernardo Pereira, Fernanda Sycko Marchiano, Camila Miyagui Yonamine, José Franco da Silveira","doi":"10.1590/0074-02760240291","DOIUrl":"10.1590/0074-02760240291","url":null,"abstract":"<p><p>Here, we review the key findings on the genetic characterisation of Berenice strains of Trypanosoma cruzi isolated from a 2-year-old child, Berenice, the first patient with Chagas disease described in the literature in 1909. Be-62 and Be-78 strains were isolated from Berenice when she was 55 and 71 years old, respectively. They were comparatively studied, revealing several important genetic differences that indicated the presence of heterogeneous T. cruzi populations within the infection of patient Berenice. Recently, a high-quality whole-genome assembly was generated using the strain Be-62, which was isolated in 1962. Even after decades-long persistence in the patient, there is a high level of conservation in synteny between Be-62 and different T. cruzi lineages. It has been suggested that T. cruzi diversity is driven by the evolution of multigene families encoding target antigens of anti-parasite immune responses, located in disruptive regions of the genome. Most studies of Berenice have been conducted on genomic bulk samples, resulting in a biased analysis that favours the dominant genotype. Single-cell omics technologies enable us to study the genetic diversity within an infection caused by protozoan parasites in detail. Sequencing individual genomes of Berenice strains will be the key to elucidating the population structure of individual infections, the dynamics of parasite populations, and adaptive mechanisms.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240291"},"PeriodicalIF":2.5,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12286610/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144690757","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":"Population structure of Anopheles (Kerteszia) bellator in the Brazilian Atlantic Forest.","authors":"Iara Carolini Pinheiro, Kamila Voges, Andre Akira Gonzaga Yoshikawa, Sabrina Fernandes Cardoso, Antonio Bernardo Carvalho, André Nóbrega Pitaluga, Luísa Damazio Pitaluga Rona","doi":"10.1590/0074-02760240287","DOIUrl":"10.1590/0074-02760240287","url":null,"abstract":"<p><strong>Background: </strong>Malaria, caused by protozoa of the genus Plasmodium and transmitted by Anopheles mosquitoes, remains a significant global health concern. In 2022, approximately 249 million malaria cases were reported worldwide, including 163,000 in Brazil. In the Atlantic Forest, An. bellator and An. cruzii are the primary vectors of malaria transmission.</p><p><strong>Objectives: </strong>This study used a cytochrome C oxidase I (COI) gene fragment to investigate the genetic population structure of An. bellator in the Brazilian Atlantic Forest.</p><p><strong>Methods: </strong>Mosquitoes were collected from Itaparica (BA), Camacan (BA), Ilha Grande (RJ), Antonina (PR), Ilha do Mel (PR), and Florianópolis (SC). They were morphologically identified and individually photographed. DNA was extracted, and a COI gene fragment was amplified using polymerase chain reaction (PCR), purified, and sequenced. Additionally, sequences from Trinidad, Colombia, and São Paulo State, obtained from GenBank, were included in the analysis. These sequences were used for molecular identification, genetic variation analysis within and between populations, and phylogenetic assessment.</p><p><strong>Findings: </strong>The analysis revealed that the An. bellator population from Trinidad is genetically distinct from all analysed populations. Furthermore, the Camacan population forms a distinct group separate from the Itaparica population, with both differing from the southern Brazilian populations and that of Colombia. Additionally, the data suggest that the southern Brazilian populations may represent distinct incipient species, particularly the Ilha Grande sample. This divergence is strongly supported by fixed genetic differences, high F ST values, and genealogical analysis.</p><p><strong>Main conclusion: </strong>The findings provide strong evidence of cryptic species within An. bellator, which appears to consist of at least three sibling groups: one from Trinidad and Tobago; An. bellator B, which includes sequences from Camacan; and An. bellator A, which contains sequences from Colombia, Itaparica, Ilha Grande, São Paulo, Florianópolis, Ilha do Mel, and Antonina. Despite its geographical proximity to Camacan (280 km), the Itaparica population clusters with southern populations ~2,000 km away, while remaining genetically distinct from them. Additionally, the study identified higher F ST values between the Ilha Grande population and other southern Brazilian samples, highlighting further genetic divergence.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240287"},"PeriodicalIF":2.5,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12286609/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144690759","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":"A 20-month longitudinal study to evaluate humoral and cellular immunity after COVID-19 vaccines.","authors":"Wlademir Braga Salgado Sobrinho, Bárbara Batista Salgado, Aguyda Rayany Cavalcante Barbosa, Vanessa Araújo Passos, Lisvane Paes Vieira, Lhorruama Dias do Nascimento, Jaila Dias Borges Lalwani, Pritesh Jaychand Lalwani, Paulo Afonso Nogueira","doi":"10.1590/0074-02760240193","DOIUrl":"10.1590/0074-02760240193","url":null,"abstract":"<p><strong>Background: </strong>The effectiveness of coronavirus disease 2019 (COVID-19) vaccines is well established; however, the long-term durability of vaccine-induced immunity remains to be fully elucidated.</p><p><strong>Objectives: </strong>This study longitudinally compared humoral and cellular immune responses in two groups: G1, who received two doses of Sinovac-CoronaVac, and G2, who received two doses of AstraZeneca-Oxford, both subsequently boosted with Pfizer.</p><p><strong>Methods: </strong>Immune responses were assessed at five time points: P1 (prior to the second dose), P2 (90-180 days after the second dose), P3 (pre-booster, six-eight months post-second dose), P4 (90-180 days post-booster), and P5 (180-270 days post-booster). Anti-Spike severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG levels were measured by enzyme-linked immunosorbent assay (ELISA), while IFNγ-producing cells in response to Spike peptides were quantified using enzyme-linked immune absorbent spot (ELISPOT). IgG subclasses were analysed in a subset of samples.</p><p><strong>Results: </strong>Following the first dose, Sinovac-CoronaVac induced lower anti-Spike IgG levels than AstraZeneca-Oxford, though levels equalised after the second dose. After the Pfizer booster, anti-Spike IgG levels remained elevated for up to six months in both groups. IgG1 was predominant in both groups, with occasional expression of IgG2 and IgG4. The mean frequency of IFNγ-producing cells was lower in the Sinovac-CoronaVac group before and up to six months after the second dose, compared to AstraZeneca-Oxford. However, post-Pfizer booster, both means became comparable. Between 90-180 days post-booster, the Sinovac-CoronaVac + Pfizer group exhibited a statistically significant decline in IFNγ-producing cells relative to the AstraZeneca-Oxford + Pfizer group. By P5, over half of individuals in the Sinovac-CoronaVac + Pfizer group demonstrated no detectable cellular response.</p><p><strong>Main conclusions: </strong>High antibody levels were maintained for up to six months following both homologous and heterologous vaccination. However, cellular immunity declined more markedly in the Sinovac-CoronaVac + Pfizer group, resulting in a higher proportion of non-responders. These findings underscore the importance of tailored booster strategies to sustain protective immunity against COVID-19.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240193"},"PeriodicalIF":2.5,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12274068/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144690756","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":"Chagas disease in Brazil: new challenges and perspectives for old problems.","authors":"Fred Luciano Neves Santos, Veruska Maia da Costa, Rafaella Albuquerque E Silva","doi":"10.1590/0074-02760240279","DOIUrl":"10.1590/0074-02760240279","url":null,"abstract":"<p><p>Mandatory notification of chronic Chagas disease (CD) is vital for improving public health responses in Brazil, where millions are affected. Implemented nationally in 2020 and supported by the \"e-SUS Notifica\" platform in 2023, this system enables accurate disease burden assessment, early diagnosis, and treatment planning. It facilitates resource allocation and targeted interventions, addressing gaps in surveillance and care. Expanding these efforts and ensuring access to treatment is essential for Brazil's goal of eliminating CD by 2030.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240279"},"PeriodicalIF":2.5,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12274067/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144690758","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":"Susceptibility of Aedes aegypti to spinosad larvicide and space spray adulticides in Brazil.","authors":"Luciana Dos Santos Dias, Ademir Jesus Martins, Cynara de Melo Rodovalho, Diogo Fernandes Bellinato, Tatiana Mingote Ferreira de Ázara, Aline Machado Rapello do Nascimento, Vincent Corbel, Maria de Lourdes da Graça Macoris, Maria Teresa Macoris Andrighetti, José Bento Pereira Lima","doi":"10.1590/0074-02760240270","DOIUrl":"10.1590/0074-02760240270","url":null,"abstract":"<p><strong>Background: </strong>Insecticides play a critical role in controlling insect vectors, particularly during epidemics. Effective chemical control relies on the robust monitoring of insecticide resistance to guide evidence-based decision-making in vector control strategies.</p><p><strong>Objectives: </strong>This study assessed the susceptibility of Aedes aegypti, the primary vector of dengue, Zika, and Chikungunya viruses, to various larvicides and adulticides deployed during Brazil's national campaigns from 2020 to 2023.</p><p><strong>Methods: </strong>Mosquito collection was performed in 46 Brazilian municipalities using ovitraps. Eggs were transported to FIOCRUZ to establish the F1 and F2 generations. The Rockefeller strain was employed to determine the discriminating concentrations (DC) for the larvicide Natular™ 20EC (spinosad) and the adulticides Cielo™ (imidacloprid and prallethrin) and Fludora® Fusion (clothianidin and deltamethrin) using a modified World Health Organization (WHO) bottle bioassay. These DCs were then used to estimate the resistance status of Ae. aegypti populations in the tested formulations. Resistance intensity was assessed by exposing mosquitoes to five, 10, or 20 times the DC concentrations.</p><p><strong>Findings: </strong>All Ae. aegypti populations were fully susceptible to larvicide spinosad. However, resistance to both adulticide formulations was detected based on WHO criteria (mortality rates < 90%). Intensity assays revealed high to very high resistance to combined adulticide products.</p><p><strong>Main conclusions: </strong>Our findings indicate the full susceptibility of Ae. aegypti populations in Brazil to spinosad, but substantial resistance to adulticides used in space spraying and residual applications, likely due to pre-existing pyrethroid resistance. However, the specific contributions of each active ingredient remain unclear, owing to the evaluation of the combined formulations. The efficacy of both traditional and alternative vector control strategies must be continuously evaluated and closely monitored to ensure the real-time assessment of their performance. For chemical control, future studies should prioritise the assessment of combination products in field trials, refining laboratory assays, and sustaining insecticide resistance surveillance to optimise control efforts in Brazil.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240270"},"PeriodicalIF":2.5,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12252664/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144642927","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}