Acta tropica最新文献

{"title":"Toxicosis in human and domestic hosts caused by ixodid ticks detected with Anaplasma platys and Hepatozoon ayorgbor.","authors":"Shafi Ullah, Jing Zhao, Mashal M Almutairi, Adil Mohammad, Irum Liaqat, Mohibullah Shah, Zhihua Sun, Abid Ali","doi":"10.1016/j.actatropica.2025.107857","DOIUrl":"https://doi.org/10.1016/j.actatropica.2025.107857","url":null,"abstract":"<p><p>Ticks are hematophagous ectoparasites that pose substantial threats by vectoring several pathogens and by directly inducing tick toxicosis both in animals and humans. No studies have reported tick toxicosis in humans or animals in Pakistan. This study aimed to investigate tick toxicosis in human and animals, and screen these ticks for tick-borne pathogens. A human toxicosis case was observed in District Lakki Marwat, where 51-years-old male farmer was bitten by Hyalomma scupense. A total of 239 hosts were examined for tick toxicosis in the five districts of northern Pakistan, in which 54 hosts including 33 goats, 13 sheep and 8 donkeys were observed having clinical signs of toxicosis. A total of 912 ticks were collected from affected hosts; the morphological identification of ticks revealed the presence of five hard tick species including Hyalomma anatolicum (181/912, 19.8%), Hyalomma isaaci (148/912, 16.2%), Hyalomma montgomeryi (137/912, 15.0%), Haemaphysalis bispinosa (159/912, 17.4%), Rhipicephalus microplus (130/912, 14.3%) and Rhipicephalus haemaphysaloides (157/912, 17.2%). Molecular analysis of 90 subjected ticks confirmed 22 positive ticks with an infection rate of 24.4%, in which 15 ticks were positive for Anaplasma platys and seven for Hepatozoon ayorgbor. The results of the current study highlighted the threat by ticks through toxicosis and possible transmission of pathogens like A. platys and He. ayorgbor. These results emphasized conducting comprehensive studies regarding the observation of early tick toxicosis and molecular screening of other pathogens.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"107857"},"PeriodicalIF":2.5,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145228608","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":"Microbiome of Dipteran vectors associated with integron and antibiotic resistance genes in South Korea.","authors":"Xavier Chavarria, Arwa Shatta, Hyun Seo Park, Du-Yeol Choi, Dongjun Kang, Singeun Oh, Dawon Lee, Myungjun Kim, Jun Ho Choi, Yoon Hee Cho, Myung-Hee Yi, Ju Yeong Kim","doi":"10.1016/j.actatropica.2025.107858","DOIUrl":"https://doi.org/10.1016/j.actatropica.2025.107858","url":null,"abstract":"<p><p>The spread of antibiotic resistance genes (ARGs) across the environment and the role that organisms that interact with humans play as reservoirs of resistant bacteria pose important threats to public health. Flies are two-winged insects composing the order Diptera, which includes synanthropic species with significant ecological roles as pollinators, vectors, and decomposers. Here, we used iSeq100 metabarcoding to characterize the microbiome of six dipteran species in South Korea: Lucilia sericata, Lucilia illustris, Culex pipiens, Aedes vexans, Psychoda alternata and Clogmia albipunctata. We profiled a panel of common ARGs and performed correlation network analysis of the microbiome and resistome to identify co-occurrence patterns of bacterial bacterial amplicon sequence variants (ASVs) and resistance genes. We detected blaTEM, ermB, tetB, tetC, aac(6')-Ib-cr, cat2, sul1, qepA, int1 and int2, but no blaSHV, mecA, tetA or cat1. Notably, co-occurrence analysis showed highly mobile genes such as qepA, ermB and sul1 were associated with integron of class 1 integrase presence. These, along with aac(6')-Ib-cr were detected at higher rates across multiple species. Microbiome composition was distinct across species. amplicon sequence variants (ASVs) of Pseudomonas, Corynebacterium, Clostridium, Ignatzschineria, Bacteroides, Streptococcus, Treponema and Dietzia showed strong co-occurrence with multiple ARGs. This study contributes to the understanding of the role of dipterans as reservoirs of antibiotic resistance.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"107858"},"PeriodicalIF":2.5,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145228586","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":"Comparative stability analysis of mixed clustering algorithms for Malaysian dengue epidemiology using topological descriptors.","authors":"Ooi Cheng Jie, Nur Fariha Syaqina Zulkepli, R U Gobithaasan, Mohd Shareduwan Mohd Kasihmuddin, Nurul Syafiah Abd Naeeim, Mohd Salmi Md Noorani, Kamarul Imran Musa","doi":"10.1016/j.actatropica.2025.107769","DOIUrl":"10.1016/j.actatropica.2025.107769","url":null,"abstract":"<p><p>Dengue fever remains a significant public health challenge in Malaysia, with high case numbers reported annually. Effective control and mitigation strategies require robust analytical tools to understand transmission dynamics and guide interventions. This study utilized topological data analysis (TDA) to extract structural features from epidemiological dengue time series using Euler characteristic curve. In contrast to traditional clustering methods that rely on direct application to dataset, TDA-based approach encodes qualitative topological information which is robust to noise and effectively capture underlying transmission dynamics. A comparative stability analysis is conducted by introducing controlled perturbations (noise) to the input data and the performance are accessed using multiple external validation metrics. Taking the k-medoids clustering algorithm with 30 % noise as an example, the TDA-based clustering approach (using the Euler characteristic) demonstrated significantly greater robustness and stability across all evaluation metrics. The Adjusted Rand Index (ARI) improved by 252 %, while the Normalized Mutual Information (NMI) increased by 122.5 %. The Fowlkes-Mallows Index (FMI) rose by 67.3 %. Additional improvements are seen in V-Measure (122.5 %), Homogeneity (80 %), and Completeness (169.7 %), highlighting the superior performance of the TDA-based approach under noisy conditions. These results demonstrate the noise resistance of the TDA-based clustering method, highlighting its enhanced ability to preserve meaningful cluster structures under perturbation compared to traditional approaches. This improved robustness facilitates deeper insights into disease transmission patterns and supports more effective data-driven public health analysis.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"107769"},"PeriodicalIF":2.5,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144803194","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":"Molecular and phylogenetic insights into haemosporidian parasites in wild bird populations of Northeast Thailand.","authors":"Chanchai Santhongklam, Natthapat Prathumjorn, Chutima Luang-Arsa, Tossapol Seerintra, Tongjit Thanchomnang, Supawadee Piratae","doi":"10.1016/j.actatropica.2025.107772","DOIUrl":"10.1016/j.actatropica.2025.107772","url":null,"abstract":"<p><p>Haemosporidian parasites, including Plasmodium, Haemoproteus, and Leucocytozoon, are widespread avian pathogens that significantly affect bird health and population dynamics. Despite their ecological importance, molecular data on these parasites in avian populations from Northeast Thailand remain limited. This study investigated the prevalence, genetic diversity, and phylogenetic relationships of haemosporidian parasites infecting wild birds in Maha Sarakham Province, Thailand. A total of 107 wild bird samples, comprising 61 Zebra Doves (Geopelia striata) and 46 House Sparrows (Passer domesticus) were screened for haemosporidian infection using multiplex PCR targeting the cytochrome b (cyt b) gene. The overall prevalence of haemosporidian infection was 52.3 % (56/107), with Plasmodium spp. (33.6 %) being the most common, followed by Haemoproteus spp. (29.0 %). No infections with Leucocytozoon spp. were detected. Co-infections with Plasmodium and Haemoproteus were observed in 11 House Sparrows. DNA analysis identified Plasmodium sp., P. collidatum, and Haemoproteus sp. as the predominant parasites. Phylogenetic analysis of 45 successfully sequenced samples revealed nine distinct haplotypes, including four novel lineages, three Haemoproteus (GEOSTR01, GEOSTR03, PASDOM02) and one Plasmodium (PASDOM01). Haemoproteus lineages showed strong host specificity, with those from Zebra Doves forming a distinct clade separate from passerine-associated lineages. In contrast, Plasmodium lineages exhibited broader host associations, consistent with vector-mediated transmission across species. This study contributes to the understanding of haemosporidian diversity in Thai avifauna and underscores the importance of molecular surveillance in avian disease ecology. Notably, this is the first report of the highly virulent avian malaria parasite P. collidatum in wild bird populations in Thailand.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"107772"},"PeriodicalIF":2.5,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144803195","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":"Polymeric micelles loaded with a 1,2,3-triazolium derivative: a promising strategy against tegumentary leishmaniasis.","authors":"Camila S Freitas, Daniela P Lage, Breno L Pimenta, Saulo S G Dias, Karolina O M Falcão, Isabela A G Pereira, Ana L Silva, Luciana M R Antinarelli, Raquel S B Câmara, Marcelo M Jesus, Maíza M Rodrigues, Dóris M Abrão, Grasiele S V Tavares, Miguel A Chávez-Fumagalli, Bruno A Oliveira, Myron Christodoulides, Adilson D Silva, Elaine S Coimbra, Eduardo A F Coelho","doi":"10.1016/j.actatropica.2025.107763","DOIUrl":"10.1016/j.actatropica.2025.107763","url":null,"abstract":"<p><p>Current drugs used to treat tegumentary leishmaniasis (TL) are toxic, present high cost and/or there is the emergence of resistant strains. Thus, there is requirement to identify new antileishmanial candidates and, in the present study, a 1,2,3-triazolium derivative, called Nic, was incorporated into polymeric micelles and used to treat Leishmania amazonensis-infected BALB/c mice. Animals were infected and, 60 days post-infection, they received saline, empty micelle (MIC), Nic, Nic/MIC or amphotericin B (AmpB), as drug control. At one and 30 days after therapy, animals were euthanized, and their blood samples, infected tissue and organs were collected to perform biochemical, parasitological and immunological assays. Results showed that at both time points, mice treated with Nic/MIC generated antileishmanial Th1-type cellular and humoral responses characterized by significantly higher levels (P < 0.05) of IFN-γ, IL-12, IFN-γ mRNA expression, nitrite, and IgG2a antibodies. Significant reductions in the parasite load were found by evaluating livers, spleens, draining lymph nodes and infected footpads of these animals. In addition, low levels of urea, creatinine, alanine transaminase, and aspartate transaminase were found in their sera. In conclusion, data suggest that Nic/MIC could be considered in future studies as a therapeutic candidate against TL.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"107763"},"PeriodicalIF":2.5,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144768283","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":"Targeting leishmaniasis in the Mediterranean: climate clusters and SDGs-based interventions.","authors":"Attila J Trájer","doi":"10.1016/j.actatropica.2025.107855","DOIUrl":"https://doi.org/10.1016/j.actatropica.2025.107855","url":null,"abstract":"<p><p>This study investigates the spatial and environmental patterns of cutaneous and visceral leishmaniasis across the Mediterranean region, integrating ecological, climatic, and land use variables at a regional scale. Utilizing kernel density estimation, land cover classification, Köppen climate mapping, soil type analysis, ensemble machine learning, and ecological niche clustering, the research identifies disease hotspots and key environmental predictors. Cutaneous leishmaniasis hotspots were found in southwestern Morocco, central Tunisia, the Levant, southern Turkey, and Crete, while visceral leishmaniasis clustered in central Tunisia, northern Israel, southern France, and Albania. Both diseases followed a U-shaped urbanization pattern, with cases concentrated in sparsely populated rural zones and dense urban areas. Most occurrences were associated with hot-summer Mediterranean and semi-arid climates and soil types. Random Forest and XGBoost models highlighted precipitation-related variables and specific soils as the most influential predictors. Ecological niche analysis revealed overlapping environmental spaces for both disease types, while K-means clustering defined four major environmental clusters for each. These findings offer a foundation for targeted interventions, including land rehabilitation, climate-adaptive surveillance, seasonal health alerts, and integration of vector control into urban planning. Overall, the study provides a comprehensive framework for leishmaniasis monitoring and control aligned with regional environmental contexts.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"107855"},"PeriodicalIF":2.5,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145211392","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":"Distribution of the West Nile Virus vector, Culex pipiens, in mainland Portugal: a geospatial modelling study.","authors":"Júlia Martinho, Hugo Osório, Fátima Amaro, Manuel Silva, Líbia Zé-Zé, Maria João Alves, Baltazar Nunes, Patrícia Soares","doi":"10.1016/j.actatropica.2025.107856","DOIUrl":"https://doi.org/10.1016/j.actatropica.2025.107856","url":null,"abstract":"<p><strong>Background: </strong>Culex pipiens, Portugal's most abundant mosquito, is a vector for several pathogens including the West Nile virus. Understanding its spatial distribution can contribute to vector-borne diseases control and public health planning, given Portugal's favourable climate. National-level data on its spatial distribution, especially in relation to climatic variables is limited. We aimed to predict the suitability of Culex pipiens distribution in mainland Portugal, considering climatic factors.</p><p><strong>Methods: </strong>A maximum entropy (Maxent) model was applied, using presence records for adult and larvae of Culex pipiens mosquitoes sampled across mainland Portugal between January 2017 and October 2023, as part of the REVIVE - Vector Surveillance Network program. Adults were sampled using CDC light traps and BG-Sentinel traps between May and October at random sites and year-round at point-of-entry sites. Larvae were sampled using dippers at breeding sites. Sampling bias was corrected by filtering presence records to one per 1 km² cell grid. Climatic data, including temperature, precipitation and elevation, were used as predictors.</p><p><strong>Results: </strong>Out of 6,859 records, 354 unique sites were obtained after filtering and cell-duplicate removal. Suitable habitats seem to be primarily in the northern and central coastal regions. Temperature was the most important predictor. Convenience sampling bias may be present.</p><p><strong>Conclusions: </strong>Most West Nile virus case reports have come from southern Portugal, but Culex pipiens's potential distribution covers the entire mainland territory, with seemingly higher distribution in the north. West Nile vector surveillance should be a priority in all regions to accurately assess transmission risk and implement effective control measures.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"107856"},"PeriodicalIF":2.5,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145211402","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":"Comparison of the characteristics and clinical course of patients with bacteraemia due to Burkholderia pseudomallei, Staphylococcus aureus and Escherichia coli in tropical Australia","authors":"Kelly Baker ,&nbsp;Alistair Lau ,&nbsp;Arish Soogrim ,&nbsp;Tej Shukla ,&nbsp;Jasraaj Singh ,&nbsp;Felix Torrance ,&nbsp;John Maclean ,&nbsp;Simon Smith ,&nbsp;Josh Hanson","doi":"10.1016/j.actatropica.2025.107851","DOIUrl":"10.1016/j.actatropica.2025.107851","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Background&lt;/h3&gt;&lt;div&gt;&lt;em&gt;Burkholderia pseudomallei, Staphylococcus aureus&lt;/em&gt; and &lt;em&gt;Escherichia coli&lt;/em&gt; are common causes of bacteraemia in the tropical Asia Pacific region. The 28-day mortality rate of &lt;em&gt;B. pseudomallei&lt;/em&gt; bacteraemia in Thailand has been reported to be 66%, higher than the 28-day mortality rate of bacteraemia due to &lt;em&gt;S. aureus&lt;/em&gt; (43%) and &lt;em&gt;E. coli&lt;/em&gt; (19%) in that country. Individuals living in rural and remote locations in these Thai studies had an even poorer prognosis. The mortality rates of individuals with bacteraemia due to &lt;em&gt;B. pseudomallei, S. aureus&lt;/em&gt; and &lt;em&gt;E. coli&lt;/em&gt; in countries with well-resourced health systems like Australia have not been compared directly.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Methods&lt;/h3&gt;&lt;div&gt;We examined all cases of bacteraemia due to &lt;em&gt;B. pseudomallei&lt;/em&gt; (between 2016 and 2022) and &lt;em&gt;S. aureus&lt;/em&gt; and &lt;em&gt;E. coli&lt;/em&gt; (between 2016 and 2020) in the Far North Queensland region of tropical Australia. We compared the characteristics and clinical course of these patients. We also examined the contribution of age, gender, comorbidity, remote residence and First Nations Australian status to the patients’ 30-day mortality.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;In total there were 177 (10.1%) episodes of bacteraemia due to &lt;em&gt;B. pseudomallei&lt;/em&gt;, 601 (34.3%) due to &lt;em&gt;S. aureus&lt;/em&gt; and 974 (55.6%) due to &lt;em&gt;E. coli.&lt;/em&gt; Individuals with &lt;em&gt;B. pseudomallei&lt;/em&gt; bacteraemia were younger than individuals with bacteraemia due to the other pathogens (median (interquartile range) age: 58 (47–67) versus 65 (49–77), &lt;em&gt;p&lt;/em&gt; &lt; 0.0001), they were less likely to live remotely (67/177 (37.9%) versus 730/1575 (46.4%), &lt;em&gt;p&lt;/em&gt; = 0.03) and they did not have a greater rate of severe comorbidity (Charlson Comorbidity Index ≥ 5; 59/177 (33.3%) versus 624/1572 (39.7%), &lt;em&gt;p&lt;/em&gt; = 0.10). There were 133/1752 (7.6%) who died within 30 days, which included 19/177 (10.7%) with &lt;em&gt;B. pseudomallei&lt;/em&gt; bacteraemia, 62/601 (10.3%) with &lt;em&gt;S. aureus&lt;/em&gt; bacteraemia and 52/974 (5.3%) with &lt;em&gt;E. coli&lt;/em&gt; bacteraemia. In multivariate analysis that included all 5 pre-specified patient characteristics, the year of presentation and the 3 pathogens (with &lt;em&gt;E.coli&lt;/em&gt; as the reference), &lt;em&gt;B. pseudomallei&lt;/em&gt; bacteraemia (hazard ratio (HR) (95% confidence interval (CI): 2.52 (1.48–4.31), &lt;em&gt;p&lt;/em&gt; = 0.001), &lt;em&gt;S. aureus&lt;/em&gt; bacteraemia (HR (95% CI): 2.47 (1.69–3.59), &lt;em&gt;p&lt;/em&gt; &lt; 0.0001), severe comorbidity (HR (95% CI): 2.53 (1.66–3.85), &lt;em&gt;p&lt;/em&gt; &lt; 0.0001) and age (divided by 10) (HR (95% CI): 1.19 (1.06–1.34), &lt;em&gt;p&lt;/em&gt; = 0.001) were independently associated with a higher 30-day mortality, while a rural/remote presentation (HR (95% CI): 0.53 (0.37–0.78), &lt;em&gt;p&lt;/em&gt; = 0.001) was independently associated with a lower 30-day mortality. Among patients with &lt;em&gt;B. pseudomallei&lt;/em&gt; bacteraemia, there was no association between any other of the pre-specified patient factors an","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107851"},"PeriodicalIF":2.5,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145184519","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":"First molecular detection of Bartonella spp. in seabirds (Procellariiformes and Sphenisciformes) rescued on the Brazilian coast","authors":"Daniel Antônio Braga Lee ,&nbsp;Dália Monique Ribeiro Machado ,&nbsp;Francyelly Monicke Bezerra de Moura ,&nbsp;Carolina Pacheco Bertozzi ,&nbsp;Vanessa Lanes Ribeiro ,&nbsp;Alice Pereira ,&nbsp;Jovêncio Mateus Sada ,&nbsp;Anna Claudia Baumel Mongruel ,&nbsp;Amir Salvador Alabí Córdova ,&nbsp;Rosangela Zacarias Machado ,&nbsp;Luis Antonio Mathias ,&nbsp;Marcos Rogério André","doi":"10.1016/j.actatropica.2025.107854","DOIUrl":"10.1016/j.actatropica.2025.107854","url":null,"abstract":"<div><div>The present study aimed to investigate the occurrence and molecular identity of <em>Bartonella</em> spp. in Procellariiformes and Magellanic penguins (<em>Spheniscus magellanicus</em>) rescued along the southern and southeastern coasts of Brazil. A total of 52 blood samples from twelve Procellariiformes species and 170 blood samples and 30 spleen samples from Magellanic penguins were collected along the coasts of Santa Catarina and São Paulo states. Following DNA extraction, all samples were screened by conventional PCR targeting the avian <em>β-actin</em> endogenous gene. Successfully amplified samples were further tested by qPCR targeting the 16S–23S ribosomal DNA internal transcribed spacer (ITS) region for <em>Bartonella</em> detection. Positive samples were subjected to additional conventional PCR assays targeting the <em>gltA, ftsZ, groEL, nuoG, pap31, rpoB, ribC</em>, and 16S–23S (ITS) genic regions for molecular characterization. Overall, 56 samples (22.2 %; 56/252) tested positive in the screening, including five blood samples from Procellariiformes (<em>Thalassarche melanophris</em>, n=3; <em>Thalassarche chlororhynchos</em>, n=2) and 51 biological samples (91.1 %; 51/56) from <em>S. magellanicus</em> (42 spleen, 9 blood). Molecular characterization was successful only for <em>S. magellanicus</em>, with amplification of <em>nuoG</em> (14.2 %; 8/56; four spleens, four blood samples), <em>rpoB</em> (12.5 %; 7/56; four spleens, three blood samples), and ITS (12.5 %; 7/56; four spleens, three blood samples). The obtained sequences were closely related to <em>Bartonella henselae</em> previously detected in humans, cats, mongooses, and ticks associated with Passeriformes. In conclusion, <em>Bartonella</em> genotypes circulate in Procellariiformes, and genotypes closely related to <em>B. henselae</em> are present in Magellanic penguins that arrive in the Brazilian coast.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107854"},"PeriodicalIF":2.5,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145184444","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":"Sustained low-level transmission of Zika virus in the community prior to its re-emergence in Malaysia, 2007–2012","authors":"Nor Azila Muhammad Azami ,&nbsp;Meng Ling Moi ,&nbsp;Hui-Min Neoh ,&nbsp;Boekhtiar Borhanuddin ,&nbsp;Saberi Saimun ,&nbsp;Rahman Jamal","doi":"10.1016/j.actatropica.2025.107852","DOIUrl":"10.1016/j.actatropica.2025.107852","url":null,"abstract":"<div><div>During the region-wide Zika virus (ZIKV) outbreak in 2016, the number of reported ZIKV cases was lower in Malaysia than in the neighbouring countries. This study aimed to determine ZIKV seroprevalence in healthy Malaysian adults aged 30<strong>–</strong>69 years from 2007 to 2012 before the region-wide ZIKV outbreak in 2016. The study participants were recruited between 2007 and 2012 from The Malaysian Cohort project. Zika IgM and IgG reactivities in the serum samples were determined by using the DPP® Zika IgM/IgG Assay System and validated using the ELISA and plaque reduction neutralization test assays. From 913 subjects, 2.0 % and 1.1 % subjects were found to be probable Zika seropositive and Zika seropositive, respectively. In probable Zika seropositive, there is significant differences in seroprevalence among age group and employment status but none in Zika seropositive. Individuals positive for both Zika and dengue antibodies were more likely to be dengue seropositive, with the detected Zika antibodies likely due to cross-reactive neutralizing activity between flaviviruses. ZIKV circulated in Malaysia at low levels in Malaysia prior to the 2016 region-wide outbreak. The high levels of neutralizing antibodies against dengue probably contributed to low number of ZIKV infection in Malaysia during the 2016 ZIKV outbreak.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107852"},"PeriodicalIF":2.5,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145181799","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}