Acta tropica最新文献

{"title":"Climate-driven expansion of climatic suitability for Phlebotomus mascittii at its northern distribution margin in Western Europe under future socioeconomic scenarios.","authors":"Pedro Pérez-Cutillas, José Risueño, Elena Verdú-Serrano, Francis Schaffner, Eduardo Berriatua","doi":"10.1016/j.actatropica.2026.108315","DOIUrl":"https://doi.org/10.1016/j.actatropica.2026.108315","url":null,"abstract":"<p><p>Climate change is expected to drive the northward expansion of phlebotomine sand flies in Europe, increasing the potential for transmission of vector-borne pathogens such as Leishmania infantum. This study assessed the historical baseline and future climatic suitability for Phlebotomus mascittii, the northernmost distributed sand fly species in Europe, across Western Europe. A mixed-effects logistic regression model was developed using summer climatic variables and land cover data, based on standardised field surveys conducted in 2023-2024 across France, Germany, Luxembourg, Belgium, and the Netherlands. The model was applied to project future suitability under three Shared Socioeconomic Pathways (SSP2-4.5, SSP3-7.0, SSP5-8.5) for the periods 2041-2060 and 2081-2100. Results indicate an increase of 20-30 percentage points in predicted climatic suitability relative to the historical baseline across Luxembourg, Belgium, western Germany, and the southern Netherlands by 2041-2060 under all SSP scenarios. By 2081-2100, this expansion intensifies, reaching projected average increases in climatic suitability across the study area of approximately 28 percentage points under SSP2-4.5, 45 percentage points under SSP3-7.0, and 57 percentage points under SSP5-8.5, with the largest increases occurring in the northernmost regions. The model showed moderate discrimination (AUC = 0.74, 95% CI: 0.68-0.80), with grouped 5-fold cross-validation yielding a mean AUC of 0.71. At the optimal threshold (0.164), apparent sensitivity was 0.55 and specificity 0.83 (accuracy = 0.80; TSS = 0.39). Accordingly, the projections should be interpreted as indicators of areas with increasing climatic suitability rather than precise predictions of future species occurrence, establishment, or pathogen transmission. Overall, the findings suggest that climate change may substantially expand climatically suitable areas for Ph. mascittii in the northern distribution margin in Western Europe, highlighting the need for adaptive surveillance and providing a spatial framework to support targeted vector surveillance and future One Health preparedness.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"108315"},"PeriodicalIF":2.6,"publicationDate":"2026-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148890761","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":"Quantitative Meta-Analytic Framework for Aedes Habitat Heterogeneity.","authors":"Moeen Hamid Bukhari, Iftikhar U Sikder, Naisha Tariq, Sandy Yun, Sare Ilknur Yavasoglu, Seok Mui Wang, Jurgen Pilz, Rajiv Ravi, Claudia Maria Elisa Romero Vivas, J E Rod, Gabriel L Hamer, Ubydul Haque","doi":"10.1016/j.actatropica.2026.108317","DOIUrl":"https://doi.org/10.1016/j.actatropica.2026.108317","url":null,"abstract":"<p><p>Aedes aegypti and Aedes albopictus are invasive mosquitoes and the primary vectors of dengue, Zika, yellow fever, and chikungunya. Their ecological traits, particularly larval habitats and adult resting sites, are critical for designing effective strategies to reduce mosquito abundance and disease transmission. A systematic review was conducted following the PRISMA 2020 guidelines to identify studies published between January 1998 and December 2024 in PubMed, Embase, Scopus, and Web of Science. We implemented a random-effects model to estimate the relative abundance of adult female Ae. aegypti and Ae. albopictus across indoor and outdoor environments, adjusted for variability across studies. Associations between larval sites, sample types, mosquito capture methods, season, and relative mosquito abundance were evaluated using meta-regression analysis. Of 9,270 publications, 38 studies met the inclusion criteria, representing 18 countries across Asia, Africa, and the Americas. Combined data showed that 15% of Ae. aegypti and Ae. albopictus were collected indoors and 85% outdoors. In studies sampling both settings, 49.43% (95% CI: 37.34 to 61.57) of Ae. aegypti were collected indoors and 56.54% (95% CI: 43.79 to 68.87) outdoors, whereas 39.78% (95% CI: 18.81 to 62.94) of Ae. albopictus were collected indoors and 62.02% (95% CI: 47.86 to 75.21) outdoors. Subgroup analysis showed that mosquito abundance varied according to larval site, mosquito life stage, season, and sampling method. Significant associations between mosquito abundance and larval sites, sample types, mosquito capture methods, and season were identified, although these associations differed by species, sampling method, and collection setting. Overall, Ae. aegypti and Ae. albopictus were more abundant outdoors, whereas Ae. aegypti showed greater indoor abundance than Ae. albopictus. Applying these findings can strengthen arbovirus surveillance and vector control through targeted monitoring of Aedes populations and ecological preferences.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"108317"},"PeriodicalIF":2.6,"publicationDate":"2026-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148890786","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":"Comet assay analysis of multigenerational genomic instability (F0-F2) in Aedes aegypti exposed to gamma radiation in Sterile Insect Technique.","authors":"Edvane Borges da Silva, Samuel Lima de Santana, Ademir Amaral, Maria Alice Varjal de Melo Santos, Claudia Rhode, Marcela Maria Pereira de Lemos Pinto Moura, Simey de Souza Leão Pereira Magnata, Liderlânio de Almeida Araújo, André Maciel Netto","doi":"10.1016/j.actatropica.2026.108312","DOIUrl":"https://doi.org/10.1016/j.actatropica.2026.108312","url":null,"abstract":"<p><p>The use of irradiation in the Sterile Insect Technique (SIT) is a sustainable and environmentally friendly strategy for controlling Aedes aegypti populations by the release of sterile males. However, the potential toxic effects of radiation on mosquito genetic material, as well as the heritability of such damage, remain insufficiently understood. In this study, we evaluated gamma radiation-induced DNA damage (20, 30, 40, and 50 Gy) in male pupae (F0 generation) and assessed the persistence of these effects in subsequent generations (F1 and F2) using the comet assay in hemocytes. In the parental generation, a significant dose-response relationship was observed, with increasing radiation doses associated with higher damage index and damage frequency (p < 0.05). In the F1 generation, both larvae and adults exhibited significantly greater DNA damage than the control group, particularly at doses of 30 and 40 Gy, supporting the inheritance of radiation-induced genomic instability. In the F2 generation, genotoxic effects were attenuated, although residual damage remained detectable in adults, suggesting partial recovery of genomic stability, possibly influenced by DNA repair mechanisms and/or selective pressures. No viable offspring were obtained at 50 Gy, confirming the sterilizing efficacy of higher doses. Integration of comet assay results with micronucleus data and reproductive parameters reinforces the association between DNA damage, mutagenic effects, and reduced fertility. These findings indicate that radiation-induced genotoxic effects may persist beyond the irradiated generation but tend to decline across generations. Overall, this study provides insights into the balance between achieving sterility and preserving biological quality in SIT programs, contributing to optimizing radiation doses and enhancing the safety and efficacy of vector control strategies.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"108312"},"PeriodicalIF":2.6,"publicationDate":"2026-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148890774","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":"Antiviral responses of Aedes mosquitoes to Old World alphaviruses.","authors":"Yin Jie Ong, Yoke Fun Chan, Wenn-Chyau Lee, I-Ching Sam","doi":"10.1016/j.actatropica.2026.108314","DOIUrl":"https://doi.org/10.1016/j.actatropica.2026.108314","url":null,"abstract":"<p><p>Aedes (Ae.) aegypti and Ae. albopictus are efficient vectors of medically important Old World alphaviruses including chikungunya virus. In contrast to the well-characterized responses to orthoflavivirus infections, antiviral defense against alphaviruses in Aedes mosquitoes remains comparatively underexplored. This review summarizes current knowledge of antiviral defense mechanisms in Ae. aegypti and Ae. albopictus, integrating insights from both intrinsic immune responses and extrinsic antiviral factors to translational relevance. RNA interference (RNAi) dominates the antiviral defense against alphaviruses, whereas canonical immune signaling pathways, including Toll, IMD, JAK/STAT and JNK demonstrate relatively limited, transient or species-specific activity. To establish persistent infections, alphaviruses have developed various immune evasion strategies, such as the expression of viral suppressors of RNAi (VSRs) as an RNAi counter-mechanism. Beyond acute antiviral responses, piRNAs derived from viral-derived DNA (vDNA) and endogenous viral elements (EVE) have been proposed to contribute to long-term immune memory. In addition to intrinsic immune defenses, superinfection exclusion and Wolbachia infection further shape vector competence to alphaviruses. Together, this review describes RNAi as the central defense relative to the context-dependent canonical signaling pathways, extrinsic factors to influence vector competence such as microbial interaction and superinfection exclusion, and highlights key concepts and challenges necessary for designing effective and sustainable arbovirus control strategies.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"108314"},"PeriodicalIF":2.6,"publicationDate":"2026-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148890821","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":"Mycoplasma and Bartonella in Cats from the Tropical Tourist Gili Islands, Indonesia.","authors":"Zeinab Sinaei, Rosanna Zobba, Beatrice Rizzi, Kholik Kholik, Valentina Chisu, Carla Cacciotto, Emanuela Bazzoni, Laura Giua, Carlotta Pasetto, Titi Gustiati Faridah, Nina Astolfi, Giovanna Masala, Alberto Alberti","doi":"10.1016/j.actatropica.2026.108309","DOIUrl":"https://doi.org/10.1016/j.actatropica.2026.108309","url":null,"abstract":"<p><p>Bartonella spp. and haemotropic Mycoplasma spp. are important vector-borne bacteria of veterinary and zoonotic relevance, yet information on their circulation in Indonesian island ecosystems remains limited. We investigated their occurrence and molecular diversity in 117 domestic and free-roaming cats from the Gili Islands, Indonesia, using full-length 16S rRNA nanopore metagenomics followed by targeted PCR, sequencing, phylogenetic analysis and multilocus sequence typing (MLST). Bartonella DNA was detected in 18/117 (15.4%) cats and haemotropic Mycoplasma DNA in 40/117 (34.2%). Sequence analysis identified Bartonella henselae as the predominant species together with Bartonella clarridgeiae. MLST of B. henselae revealed three sequence types (ST1, ST16 and ST42), with ST1, a lineage reported in both feline and human isolates, predominating. Comparison with the PubMLST database showed significant geographical differences in the distribution of ST1 and ST42, supporting regional variation in the circulation of B. henselae lineages. Haemoplasma characterization identified Candidatus Mycoplasma haemominutum, Mycoplasma haemofelis, Candidatus Mycoplasma turicensis and a Mycoplasma feliminutum-like organism, comprising ten distinct sequence variants. Haemoplasma positivity was significantly associated with age, with adults showing higher positivity than younger animals (P < 0.001), whereas Bartonella infection was not associated with age, sex or island of origin. The detection of zoonotically relevant B. henselae lineages and the genetic diversity of feline haemoplasmas provide evidence of the circulation of vector-borne bacteria among cats in this tropical island ecosystem. These findings provide the first molecular epidemiological baseline for this region and contribute to understanding the circulation and genetic diversity of feline vector-borne pathogens in Southeast Asia.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"108309"},"PeriodicalIF":2.6,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148885920","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":"INTEGRATIVE TAXONOMY OF PHLEBOTOMINE SAND FLIES OF THE GENUS Sciopemyia BARRETTO, 1962.","authors":"Salvador Paganella Chaves Júnior, Bruno Leite Rodrigues, Monique Paiva de Campos, Fabiano Borges Figueiredo, Andrey José de Andrade, Paloma Helena Fernandes Shimabukuro","doi":"10.1016/j.actatropica.2026.108311","DOIUrl":"https://doi.org/10.1016/j.actatropica.2026.108311","url":null,"abstract":"<p><p>The genus Sciopemyia Barretto, 1962 comprises 12 species and presents important taxonomic challenges, including species described from a single sex, morphologically similar females, and the occurrence of a species complex within Sciopemyia sordellii (Shannon & Del Ponte, 1927). To clarify the taxonomic status of the genus, an integrative taxonomy approach was applied, combining molecular data and wing geometric morphometrics (WGM). Sequences of a fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene from 10 Sciopemyia species were analysed together with previously published sequences using four single-locus species-delimitation methods to evaluate the correspondence between molecular units and nominal species. In the WGM analyses, 13 landmarks were selected and subjected to different statistical analyses to discriminate 11 species. A total of 53 COI sequences were amplified and analysed. Maximum intraspecific genetic distances ranged from 0.0% to 13.53%, whereas minimum interspecific distances ranged from 3.77% to 13.53%. However, for some species, only a single sequence was analyzed, which may not accurately reflect the true intraspecific variability. The COI-based phylogeny and molecular species-delimitation methods grouped the sequences into at least one well-supported clade for each nominal species, except for the pair Sciopemyia apicalis/S. sordellii. Cryptic diversity was detected in S. sordellii, S. servulolimai and S. shimabukuroae, generally associated with geographical distribution or biome. In addition, COI sequences were obtained for the first time for S. apicalis, S. birali, S. nematoducta and S. shimabukuroae. Wing geometric morphometrics did not clearly separate the species, grouping them into two main clusters. However, these patterns were congruent with the morphological taxonomy of the genus, DNA-based taxonomy and the geographical distribution of the species.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"108311"},"PeriodicalIF":2.6,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148878784","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":"No Longer at Ease: Priority Effects and Niche Modification in Larval Interactions of Aedes albopictus, Aedes aegypti, and Culex pipiens.","authors":"Fatma Bursali, Mustapha Touray","doi":"10.1016/j.actatropica.2026.108307","DOIUrl":"https://doi.org/10.1016/j.actatropica.2026.108307","url":null,"abstract":"<p><p>Mosquito larvae may compete for resources or space in shared habitats with limited nutrients by resource exploitation or defence or both. In container habitats, the sequence of colonization often dictates community assembly. We examined how arrival order and temporal lags (3 and 7 days) influence the competitive outcomes between invasive Aedes aegypti, Ae. albopictus, and resident Culex pipiens. Studies on the magnitude of priority effects in these systems are lacking. Larvae were added simultaneously and sequentially (after 3 and 7 days) to the dynamics between these mosquito species. Results indicate that simultaneous introduction maximizes competitive stress, resulting in significant mortality and reduced wing length across all species. Conversely, early colonizers gained a distinct fitness advantage; a 3-7-day head start significantly enhanced survival and growth, while late-arriving cohorts were severely suppressed. While Ae. aegypti typically maintained competitive dominance, this advantage diminished when Culex established priority. Results from conditioned-water treatments mirrored live-larval interactions, suggesting that chemical and microbial modifications are primary drivers of these priority effects. Adult behavioural responses of adult mosquitoes to competition was also assessed to determine whether females avoid exposing their offspring to competitive environments when possible. Gravid females exhibited clear discrimination when presented with conspecific-conditioned, heterospecific-conditioned, and dechlorinated water. The general avoidance of heterospecific-conditioned water suggests that chemical cues guide oviposition decisions, potentially functioning as a mechanism to bypass competitive pressures in natural habitats. Understanding these mechanisms is essential for predicting invasion outcomes and for designing vector control strategies that exploit natural competitive asymmetries.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"108307"},"PeriodicalIF":2.6,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148878778","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":"Genetic polymorphism in Plasmodium falciparum MSPDBL1 and MSPDBL2 and their impact on B- and T-cell immunodominant epitopes in Brazilian malaria-endemic areas.","authors":"Juliana Aline Souza Lemos, Barbara de Oliveira Baptista, Lana Bitencourt Chaves, Hugo Amorim Dos Santos de Souza, Jenifer Peixoto de Barros, Rodrigo Medeiros Martorano, Rodrigo Nunes Rodrigues-da-Silva, Evelyn Kety Pratt Riccio, Paulo Renato Rivas Totino, Josué da Costa Lima-Júnior, Cláudio Tadeu Daniel-Ribeiro, Lilian Rose Pratt-Riccio","doi":"10.1016/j.actatropica.2026.108308","DOIUrl":"https://doi.org/10.1016/j.actatropica.2026.108308","url":null,"abstract":"<p><p>Merozoite Surface Protein Duffy Binding-like 1 and 2 (MSPDBL1 and MSPDBL2) are involved in erythrocyte invasion by Plasmodium falciparum. Antibodies targeting PfMSPDBL1 and PfMSPDBL2 show strong opsonizing and growth-inhibitory activities, supporting their potential as asexual blood-stage vaccine candidates. Given that the extensive genetic diversity of P. falciparum contributes to immune evasion, identifying polymorphisms in regions encoding PfMSPDBL1 and PfMSPDBL2 is essential to assess their relevance as vaccine targets. In this study, we investigated polymorphisms in the pfmspdbl1 and pfmspdbl2 genes and their impact on potentially antigenic regions within the Duffy Binding-like (DBL) and Secreted Polymorphic Antigen Associated with Merozoite (SPAM) domains. Blood samples were collected from 47 P. falciparum-infected individuals from three malaria-endemic areas of the Brazilian Amazon. Genomic DNA was extracted, PCR-amplified, and sequenced. Intrapopulation genetic diversity and Tajima's D values were estimated using bioinformatics tools. Linear B- and T-cell epitopes were predicted using BCPreds and IEDB (Immune Epitope Database), respectively. Two and thirty-two polymorphisms were identified in pfmspdbl1 within the SPAM and DBL domains, respectively, whereas pfmspdbl2 presented two polymorphisms across both domains and a 12 bp insertion in the SPAM domain. Tajima's D values were positive across domains, except for the DBL domain of pfmspdbl2 in Mâncio Lima. Fifteen B-cell and fifteen T-cell epitopes were predicted, with polymorphisms in three B-cell epitopes affecting Vaxijen scores. Together, these findings reveal contrasting evolutionary patterns between PfMSPDBL1 and PfMSPDBL2, with potential implications for antigenicity, and highlight PfMSPDBL2 as a potential candidate for further evaluation in multicomponent blood-stage malaria vaccine development.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"108308"},"PeriodicalIF":2.6,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148872635","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 review of ticks and tick-borne diseases in Southeast Asia: identifying priorities, hurdles, and opportunities for health and knowledge gain.","authors":"Ernest Jm Teo, Mackenzie L Kwak, Nora G Cleary, Van Lun Low, Babi Kyi Soe, Michael E von Fricken, Andrew G Letizia, Keita Matsuno, Kimberly M Fornace, Benoit Malleret, Ryo Nakao","doi":"10.1016/j.actatropica.2026.108305","DOIUrl":"https://doi.org/10.1016/j.actatropica.2026.108305","url":null,"abstract":"<p><p>Ticks and tick-borne diseases (TBDs) in Southeast Asia are poorly understood, confounding surveillance, and mitigation opportunities. Herein, we conducted a survey of experts (n = 25) to identify tick species and TBDs of greatest concern to Southeast Asia, 'drivers' which may alter their impacts, and research hurdles. These experts identified Dermacentor auratus, Haemaphysalis longicornis, Rhipicephalus linnaei, Amblyomma testudinarium sensu lato, Ixodes granulatus, Ixodes persulcatus, and Rhipicephalus microplus as ticks of greatest concern; and rickettsioses, severe fever with thrombocytopenia syndrome virus, borreliosis, Crimean-Congo haemorrhagic fever, anaplasmosis, tick-borne encephalitis, and novel tick-borne viruses as TBDs of greatest concern. Land-use change was expected to have the largest impact on ticks and TBDs, followed by climate change, invasive species, and drug resistance. The three biggest research hurdles were lack of funding, lack of awareness, and lack of taxonomic expertise. Addressing these near-term priorities and hurdles while harmonizing research efforts and surveillance within, and between countries may help lay the groundwork for future research and surveillance efforts in the region, and may also enhance the region's preparedness, ultimately leading to better health outcomes for the region.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"108305"},"PeriodicalIF":2.6,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148862923","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":"COI DNA barcoding of phlebotomine sand flies from the Pamplonita River basin, Norte de Santander, Colombia.","authors":"Lizeth Eunice Bolivar-Buitrago, Diego Carrero-Sarmiento, Richard Hoyos-Lopez","doi":"10.1016/j.actatropica.2026.108298","DOIUrl":"https://doi.org/10.1016/j.actatropica.2026.108298","url":null,"abstract":"<p><p>Leishmaniasis remains a major neglected tropical disease in the Americas, where transmission involves diverse parasites, reservoirs, and phlebotomine sand fly vectors. Accurate sand fly identification is essential for surveillance, but morphology-based diagnosis may be difficult in closely related taxa and isomorphic females. This study evaluated COI DNA barcoding for identifying sand flies from the Pamplonita River basin, Colombia. Adult sand flies were collected in three ecological settings using Centers for Disease Control and Prevention (CDC) light traps, Shannon traps, and active searching. Specimens were morphologically examined and processed for DNA extraction, cytochrome c oxidase subunit I (COI) amplification, and bidirectional sequencing. Sequences were edited, aligned, screened for stop codons and indels, and analyzed using diversity estimates, Kimura two-parameter (K2P) distances, neighbor-joining (NJ), and PhyML maximum-likelihood (ML) clustering under the General Time Reversible model with invariant sites and gamma-distributed rates (GTR+I+G) with 1,000 bootstrap replicates. Sixty-two study sequences representing seven species were analyzed with three external sequences. The curated alignment contained 65 sequences of 660 bp, with no gaps or ambiguous bases. The study dataset included 24 haplotypes and 185 polymorphic sites. Mean interspecific K2P distances ranged from 3.55% between Pintomyia (Pi.) longiflocosa and Pi. torvida to 19.82% between Psathyromyia (Pa.) shannoni and Pi. evansi. Neighbor-joining and maximum-likelihood analyses recovered species-level clusters consistent with morphological assignments. COI barcoding supported the molecular discrimination of medically relevant sand flies from northeastern Colombia and provides a regional baseline for vector surveillance in an area of epidemiological interest.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"108298"},"PeriodicalIF":2.6,"publicationDate":"2026-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148860309","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}