Comparative Immunology Microbiology and Infectious Diseases最新文献

{"title":"Evaluation of community-based mass dog deworming and public health education for the control of Toxocara spp. infection in household dogs in Vietnam.","authors":"Minh-Trang Thi Hoang, Dinh Ng-Nguyen, Ketsarin Kamyingkird, Van-Phuong Ngo, Tawin Inpankaew","doi":"10.1016/j.cimid.2026.102543","DOIUrl":"https://doi.org/10.1016/j.cimid.2026.102543","url":null,"abstract":"<p><p>Toxocara spp. are neglected zoonotic nematodes that commonly infect dogs and represent an important public health concern. However, evidence on community-based control interventions remains limited. This study aimed to compare mass deworming of dogs and cats with public health education in reducing Toxocara spp. infection in household dogs. A community-based controlled intervention study was conducted between February and July 2025 in eight hamlets in Krong Nang district, Dak Lak Province, Vietnam. Four hamlets were assigned to mass deworming of pets with fenbendazole, and four to public health education. Dog fecal samples were collected at baseline and after three months and examined by copromicroscopy and polymerase chain reaction (PCR). The primary outcome was PCR-detected T. canis prevalence, and arithmetic mean infection intensity in eggs per gram (EPG). The analysis included 557 dog observations across baseline and follow-up surveys. After three months, the deworming group showed greater descriptive reductions in copromicroscopy- and PCR-detected Toxocara spp. prevalence and EPG than the education group. The relative reduction in PCR-detected T. canis prevalence was descriptively greater in the deworming group (22.1%, 95% CI: -11.4-47.3) than in the education group (3.3%, 95% CI: -39.2-34.1). However, mixed-effects logistic regression found no statistically significant intervention effect on PCR-detected T. canis infection over the three-month follow-up. Although no statistically significant intervention effect was detected, mass pet deworming showed larger descriptive reductions in Toxocara spp. infection than public health education. Further studies are needed to evaluate integrated strategies combining regular deworming, education, and environmental hygiene, which may help reduce environmental contamination and zoonotic transmission.</p>","PeriodicalId":50999,"journal":{"name":"Comparative Immunology Microbiology and Infectious Diseases","volume":"130 ","pages":"102543"},"PeriodicalIF":2.5,"publicationDate":"2026-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149289751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial susceptibility and virulence phenotypes of Escherichia coli isolated from bovine milk and feces in Brazil.","authors":"Jessica Luana Felix Moreira, Maysa Serpa Gonçalves, Dircéia Aparecida da Costa Custódio, Rafaella Silva Andrade, Geraldo Márcio da Costa, Alessandro de Sá Guimarães, Carine Rodrigues Pereira, Elaine Maria Seles Dorneles","doi":"10.1016/j.cimid.2026.102539","DOIUrl":"https://doi.org/10.1016/j.cimid.2026.102539","url":null,"abstract":"<p><p>Escherichia coli is a versatile pathogen that causes bovine mastitis and acts as a reservoir of virulence and antimicrobial resistance genes, causing risks to both animal and public health. This study characterized 83 E. coli isolates from milk samples of cows with clinical (n = 19) or subclinical mastitis (n = 33) and fecal samples from lactating cows (n = 31) in Brazil. The isolates were evaluated for phylogenetic group, antimicrobial susceptibility, extended-spectrum β-lactamase (ESBL), plasmid-mediated colistin resistance (mcr), O157 genotype, and biofilm formation. Phylogenetic classification revealed predominance of phylogroups A and B1. Antimicrobial susceptibility testing showed resistance to phenicols (38.6%), β-lactams (27.7%), polymyxins (20.5%), and tetracyclines (20.5%), with multidrug resistance (MDR) observed in 20.5% of isolates, most frequently among clinical mastitis and fecal strains. ESBL production was detected in 47.4% of the isolates evaluated, often concomitant with MDR. All isolates tested negative for the mcr genes, despite 20.5% being colistin-resistant, and were also negative for the O157 antigen. Biofilm formation was widespread, observed in 79.5% of the isolates. These results demonstrated the circulation of diverse antimicrobial-resistant profiles of E. coli strains in Brazilian dairy farms. Taken together, the coexistence of multidrug resistance, ESBL production, and biofilm-forming ability among isolates from mastitic milk and bovine feces indicates that antimicrobial-resistant E. coli strains are present in both clinical and intestinal reservoirs within dairy herds. Furthermore, the detection of colistin-resistant isolates lacking the investigated mcr genes suggests the involvement of alternative resistance mechanisms that warrant further investigation.</p>","PeriodicalId":50999,"journal":{"name":"Comparative Immunology Microbiology and Infectious Diseases","volume":"130 ","pages":"102539"},"PeriodicalIF":2.5,"publicationDate":"2026-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149289719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to Monitoring the immune landscape against rabies in domestic dogs, Japan [Clinical Immunology, Microbiology and Infectious Diseases Volume 127 (2026), 102470]","authors":"Yuri Amemiya,&nbsp;Hiroshi Nishiura","doi":"10.1016/j.cimid.2026.102511","DOIUrl":"10.1016/j.cimid.2026.102511","url":null,"abstract":"","PeriodicalId":50999,"journal":{"name":"Comparative Immunology Microbiology and Infectious Diseases","volume":"129 ","pages":"Article 102511"},"PeriodicalIF":2.5,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148702845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel lytic bacteriophage BUCT791 effectively controls multidrug-resistant Klebsiella pneumoniae in vitro and in vivo","authors":"Rashid Ahmad,&nbsp;Zakirullah,&nbsp;Amna Shafqat,&nbsp;Mengzhe Li,&nbsp;Yigang Tong","doi":"10.1016/j.cimid.2026.102498","DOIUrl":"10.1016/j.cimid.2026.102498","url":null,"abstract":"<div><div>Acute infections caused by multidrug-resistant (MDR) <em>Klebsiella pneumoniae</em> immediately necessitate the development of novel therapeutic strategies. Phage therapy offers a viable alternative for combating MDR <em>Klebsiella</em> infections. Here, we report the isolation and comprehensive characterization of a novel lytic bacteriophage, BUCT791, recovered from hospital sewage. Phage BUCT791 exhibited a short latent period (20 min), a large burst size (∼275 PFU/cell), rapid adsorption efficiency (&gt;90% within 15 min), and remarkable stability across a wide range of temperatures (4–50 °C) and pH values (3−12). Whole-genome sequencing revealed a 48,388 bp double-stranded DNA genome with a GC content of 50%, encoding 74 predicted open reading frames (ORFs) and lacking any virulence or antibiotic resistance genes, confirming its biosafety for therapeutic applications. Phylogenetic analysis assigned phage BUCT791 to the genus <em>Jedunavirus</em> (family <em>Myoviridae</em>) and identified it as a member of the species <em>Klebsiella virus FZ14</em>. In vitro assays demonstrated that BUCT791 effectively inhibited <em>Klebsiella</em> growth within 2 h and significantly inhibited biofilms formation. In vivo, phage treatment markedly improved <em>Galleria mellonella</em> larval survival from 10% to 80%. Collectively, these findings indicate that BUCT791 possesses potent antibacterial activity and represents a promising candidate for developing safe and effective phage-based therapeutics against <em>MDR Klebsiella pneumoniae</em> infections.</div></div><div><h3>Importance</h3><div>This study reports the isolation and characterization of BUCT791, a novel lytic bacteriophage active against multidrug-resistant <em>Klebsiella pneumoniae</em>. BUCT791 showed strong stability, efficient bacterial killing, antibiofilm activity, and improved survival in an in vivo infection model, supporting its potential as a promising alternative strategy against MDR <em>K. pneumoniae</em> infections.</div></div>","PeriodicalId":50999,"journal":{"name":"Comparative Immunology Microbiology and Infectious Diseases","volume":"128 ","pages":"Article 102498"},"PeriodicalIF":2.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148377807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Complete genome and phenotypic characterization of a feline-derived Bartonella henselae strain with enhanced endothelial interaction and immunomodulatory phenotypes","authors":"Yuhao Cai,&nbsp;Gengyu Yuan,&nbsp;Chunyan Wang","doi":"10.1016/j.cimid.2026.102496","DOIUrl":"10.1016/j.cimid.2026.102496","url":null,"abstract":"<div><div><em>Bartonella henselae</em> is a zoonotic pathogen capable of persistent infection through endothelial interaction and modulation of host immune responses. We hypothesized that this feline-derived strain may retain the conserved <em>B. henselae</em> virulence framework while displaying distinct virulence-associated host-cell phenotypes. In this study, we report the complete genome of a feline-derived <em>B. henselae</em> strain, CHSH_Feline, and integrate comparative genomic analysis with phenotypic characterization in endothelial and macrophage infection models. Hybrid sequencing using Oxford Nanopore long reads and Illumina short reads generated a single circular chromosome of 1957,299 bp with a GC content of 38.26%. Whole-genome average nucleotide identity and phylogenetic analyses confirmed that CHSH_Feline belongs to the core <em>B. henselae</em> lineage. Comparative genomic analysis revealed conservation of major virulence-associated systems, including the <em>virB</em>/<em>virD4</em> type IV secretion system, the <em>trw</em> system, the <em>bepA-G</em> effector cluster, and adhesin-associated loci. Protein-level comparison further identified localized sequence variation in selected host-interaction proteins, including BepF, CFA, Vomp2/BadA2, hemagglutinin repeat-containing proteins, and HecB-associated components. Functionally, CHSH_Feline induced stronger formation of endothelial invasomes, which are actin-rich membrane-associated structures containing bacterial aggregates, and promoted a more pronounced anti-inflammatory cytokine profile in macrophages, characterized by increased IL-10 and reduced TNF-α production compared with reference strains. Together, these findings show that CHSH_Feline retains the conserved <em>B. henselae</em> virulence framework while displaying enhanced virulence-associated host-cell phenotypes. The identified sequence variations provide candidate genomic features for future mechanistic studies. This work provides a complete genomic resource and phenotypic framework for understanding strain-level heterogeneity in <em>B. henselae</em> host–pathogen interactions.</div></div>","PeriodicalId":50999,"journal":{"name":"Comparative Immunology Microbiology and Infectious Diseases","volume":"128 ","pages":"Article 102496"},"PeriodicalIF":2.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148310357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Igκ and Igλ binding toward influenza virus hemagglutinin and SARS-CoV-2 Spike protein during primary viral infections in humans, mice, and pigs","authors":"Robert A. Richardson,&nbsp;J. Fletcher North,&nbsp;Matthew H. Thomas,&nbsp;Amanda Lynch,&nbsp;Constantinos S. Kyriakis,&nbsp;Giuseppe A. Sautto,&nbsp;Ted M. Ross","doi":"10.1016/j.cimid.2026.102494","DOIUrl":"10.1016/j.cimid.2026.102494","url":null,"abstract":"<div><div>An Igλ light chain bias (IgL) has been identified in ferrets after a primary influenza virus infections. To further study if this phenotype is consistent between species, serum immunoglobulin Igλ and Igκ light chain (IgL) prevalence was evaluated in humans, mice, and pigs following a primary respiratory virus infection. Each IgL population was tested for its binding capacity to the immunodominant viral glycoprotein of the infecting virus. Humans infected with their initial SARS-CoV-2 virus infection had a marginal Igκ bias against the spike (S) glycoprotein, but had no observable IgL bias toward the receptor binding domain of the S protein. Mice had an Igκ bias against the influenza virus hemagglutinin (HA) after a primary infection with an H1N1 or H3N2 influenza virus. Conversely, pigs had an Igλ bias to the HA after a primary infection with either influenza virus subtype. These results highlight that IgL biases vary in different species after a primary viral respiratory infection. Overall, these results have implications for how immunological data should be interpreted between species and the selection of animal models for various applications.</div></div>","PeriodicalId":50999,"journal":{"name":"Comparative Immunology Microbiology and Infectious Diseases","volume":"128 ","pages":"Article 102494"},"PeriodicalIF":2.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148341150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Screening candidate intermediate hosts for porcine respiratory coronavirus using molecular docking","authors":"Rochanawan Sootichote,&nbsp;Aekkapot Chamkasem,&nbsp;Waraphan Toniti,&nbsp;Micaella C. Dato,&nbsp;Pailin Chayapham,&nbsp;Dusit Laohasinnarong","doi":"10.1016/j.cimid.2026.102495","DOIUrl":"10.1016/j.cimid.2026.102495","url":null,"abstract":"<div><div>Emerging coronavirus-associated acute respiratory diseases have posed major global health and economic disruption, highlighting the ongoing risk of zoonotic spillover. Cross-species transmission is largely determined by the interaction between viral receptor-binding domains (RBDs) and host cellular receptors. This study utilizes Porcine Respiratory Coronavirus (PRCoV) as a model to investigate host adaptation via the Aminopeptidase N (APN) receptor. Using molecular docking and structural analysis, we evaluated the docking-estimated binding affinity between the PRCoV RBD and APN proteins from 18 vertebrate species. Sequence analysis revealed that <em>Camelidae</em>, <em>Bovidae</em>, and <em>Hipposiderid</em> bats share the highest similarity (70%-85%) with porcine APN (pAPN). Notably, <em>Hipposiderid</em> bats showed up to 80% similarity with both pAPN and human APN (hAPN), suggesting a significant ecological role in viral evolution. Meanwhile, avian, reptile, and aquatic species showed greater divergence from mammals, with 45–60% sequence similarity. Molecular docking results highlight the high predicted receptor compatibility among pigs, cats, bats, horses, rabbits, and cattle. While wild-type PRCoV displayed a tenfold lower affinity for hAPN (K_d 2971 pM) compared to pAPN (K_d 261 pM), specific single amino acid substitutions in the RBD enhanced binding compatibility to hAPN, reducing K_d values to below 100 pM. These RBD variants, analogous to mutations seen in SARS-CoV-2, suggest that minimal genetic shifts could increase predicted hAPN binding in the <em>in-silico</em> prediction. These findings highlight the potential for receptor-binding adaptation candidates and emphasize the importance of monitoring viral evolution and host receptor diversity to support early detection and support receptor-based surveillance and future validation.</div></div>","PeriodicalId":50999,"journal":{"name":"Comparative Immunology Microbiology and Infectious Diseases","volume":"128 ","pages":"Article 102495"},"PeriodicalIF":2.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148341142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of SARS-CoV-2 and coinfections in companion animals from COVID-19-positive owners in Southeast, Brazil","authors":"Anisleidy Pérez Castillo,&nbsp;Andressa Oliveira-Silva,&nbsp;Nícolas Colácio,&nbsp;Mariana Rodrigues Pereira,&nbsp;Paula Luize Camargos Fonseca,&nbsp;João Victor Oliveira Miranda,&nbsp;Bárbara Laterza Cerqueira,&nbsp;Vinícius Henrique Barbosa Amaral,&nbsp;Rennan Garcias Moreira,&nbsp;Viviane Campos Spanhol,&nbsp;Jenner Karlisson Pimenta dos Reis,&nbsp;Ricardo Nascimento Araujo,&nbsp;Renato Santana Aguiar,&nbsp;Júlia Angélica Gonçalves Silveira","doi":"10.1016/j.cimid.2026.102497","DOIUrl":"10.1016/j.cimid.2026.102497","url":null,"abstract":"<div><div>Zoonotic pathogens are central to the One Health framework, and the role of companion animals in SARS-CoV-2 infection, particularly in co-infection scenarios, remains unclear. This study investigated the occurrence of SARS-CoV-2, hemopathogens, and co-infections in domiciled dogs and cats from COVID-19–positive households in Southeast Brazil. Between January 2021 and August 2022, samples were collected from 86 animals (48 dogs and 38 cats) in Belo Horizonte, Minas Gerais. SARS-CoV-2 was detected by RT-qPCR, and hemopathogens were identified using nested and species-specific PCR assays. SARS-CoV-2 was detected in 9.3% (8/86) of animals, including 14.6% (7/48) of dogs and 2.6% (1/38) of cats, and one canine sample was classified as Omicron BA.1. Hemopathogens were detected in 85.4% of dogs, mainly <em>Bartonella</em> spp. (70.8%) and <em>Anaplasma</em> sp. (58.3%), with frequent co-infections. In cats, <em>Bartonella</em> spp. (15.8%) and hemotropic <em>Mycoplasma</em> spp. (21.1%) predominated. None of the animals tested positive for ther order Piroplasmida or <em>A. phagocytophilum.</em> Most SARS-CoV-2–positive animals (75.0%) were co-infected, but no significant association was observed between viral infection and hemopathogens (<em>p</em> &gt; 0.05). These findings demonstrate the circulation of SARS-CoV-2 and hemopathogens in companion animals and reinforce the relevance of One Health surveillance.</div></div>","PeriodicalId":50999,"journal":{"name":"Comparative Immunology Microbiology and Infectious Diseases","volume":"128 ","pages":"Article 102497"},"PeriodicalIF":2.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148370729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First comprehensive assessment of dipteran diversity and vectorial potential in northeastern Algeria: Ecological, veterinary, and one health perspectives","authors":"Khouloud Dekkiche ,&nbsp;Amel Benatallah ,&nbsp;Faiza Marniche","doi":"10.1016/j.cimid.2025.102438","DOIUrl":"10.1016/j.cimid.2025.102438","url":null,"abstract":"<div><div>A survey of insects was conducted at four locations in the Sétif region of northeastern Algeria: Ainarnat, Ainroua, Benifouda, and Ainazel. A total of 3924 diptera specimens belonging to 19 species and 10 families were collected. The number of species at each site varied considerably, with Ainazel having 13 species and Ainroua hosting 19. Haematophagous Diptera were dominant in all locations, with <em>Stomoxys calcitrans</em>, <em>Culex pipiens</em>, and <em>Tabanus</em> species being the most frequently recorded. Their relative abundance ranged from 31.4 % in Ainazel to 65.2 % in Benifouda. Non-haematophagous species, including saprophagous, necrophagous, nectarivorous, floricolous, and frugivorous taxa, were also well represented, particularly in Ainarnet, accounting for almost 62 % of captures. <em>Musca domestica</em> and <em>Musca autumnalis</em> predominated. The interaction between different Dipteran species varied considerably between sites. Ainroua exhibited the highest density of <em>S. calcitrans</em> (over 56 % of captures), while Benifouda displayed the greatest overall abundance (n = 1239). Although Ainazel yielded the smallest sample size (n = 414), its species composition was balanced, with <em>M. domestica</em> (46 %) and <em>S. calcitrans</em> (31 %) being dominant. Diversity indices revealed clear variations in species richness, suggesting the influence of local agroclimatic factors. The high prevalence of dipteran species of veterinary and medical interest indicates significant epidemiological risks to livestock and humans. This study provides the first comprehensive assessment of dipteran diversity and vectorial potential in northeastern Algeria, offering baseline data for future ecological and veterinary research.</div></div>","PeriodicalId":50999,"journal":{"name":"Comparative Immunology Microbiology and Infectious Diseases","volume":"126 ","pages":"Article 102438"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145845651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expansion of cluster 3 Tembusu virus in Guangdong geese with hepatitis-splenomegaly syndrome and evidence of recombination","authors":"Chen-Chen Yang ,&nbsp;Wei-Hao Tan ,&nbsp;Run-Jie Zou,&nbsp;Ying Liang,&nbsp;Xue-Lian Zhang,&nbsp;Jian-Wei Shao","doi":"10.1016/j.cimid.2026.102439","DOIUrl":"10.1016/j.cimid.2026.102439","url":null,"abstract":"<div><div>Tembusu virus (TMUV) is a mosquito-borne flavivirus that causes substantial economic losses in the Asian poultry industry. While phylogenetic Cluster 2 has historically been dominant, recent reports signal the expansion of Cluster 3. In this study, we investigated TMUV infection in geese presenting with hepatitis-splenomegaly syndrome in Guangdong, China, a major waterfowl‑producing region in China. Among 50 clinical liver samples collected in late 2024, 16 (32 %) tested positive for TMUV by semi-nested RT-PCR. Complete genome sequencing of eight selected strains revealed that all belonged to the expanding Cluster 3 and shared high intra-clade identity. Phylogenetic analyses based on complete genomes and the envelope gene confirmed their placement within Cluster 3, a lineage genetically closer to mosquito-origin viruses. Notably, comprehensive recombination analysis identified a statistically supported recombination event in strain GDQY-298. Bootscan and phylogenetic incongruence tests indicated that GDQY-298 likely originated from recombination between two co-circulating Cluster 3 strains (GDQY-273 and GD/1650/2022). Our findings provide direct evidence for the ongoing displacement of Cluster 2 by Cluster 3 in Guangdong geese, underscoring the urgent need for subclade-specific surveillance and timely vaccine updates to counter the threat posed by evolving TMUV strains.</div></div>","PeriodicalId":50999,"journal":{"name":"Comparative Immunology Microbiology and Infectious Diseases","volume":"126 ","pages":"Article 102439"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145978839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}