Four Gram-stain-positive, rod-shaped and non-spore-forming strains zg-332T, ZJ293, ZJ405T and ZJ1691 were isolated from the respiratory tract of Marmota himalayana in the Qinghai-Tibet Plateau of China. Comparative 16S rRNA gene sequence analysis revealed that strain zg-332T shares 99.6% sequence similarity with strain ZJ293 and is most similar to strain Pauljensenia hongkongensis DSM 15629T. In contrast, strains ZJ405T and ZJ1691 share 99.7% similarity with each other and are most closely related to strain Schaalia vaccimaxillae DSM 15804T and strain Schaalia cardiffensis CCUG 44997T. Phylogenetic analyses based on 16S rRNA gene sequences confirmed these groupings. The G+C content of strains zg-332T and ZJ405T is 35.4 mol% and 57.9 mol%, respectively. Comparative genomic analysis indicated that strains zg-332T and ZJ293 represent a novel genus in the family Actinomycetaceae, whereas strains ZJ405T and ZJ1691 represent a novel species within the genus Schaalia. Optimal growth occurred at 35.0 °C, pH 8.0 with 0.5% NaCl (w/v) for strain zg-332T, and 37.0 °C, pH 8.0 with 0.5-1.5% NaCl (w/v) for strain ZJ405T. The major fatty acids are C16 : 0 and C18 : 1 ω9c for both strains zg-332T and ZJ405T. The polar lipids for both strains include diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and unidentified glycolipids, with additional phosphatidyl inositol mannosides, unidentified phospholipid for strain zg-332T and unidentified lipids for strain ZJ405T. The respiratory quinone of strain zg-332T is MK-9(H2) and MK-9(H4), and that of strain ZJ405T is MK-10(H4). The peptidoglycan of both strains zg-332T and ZJ405T contains alanine, glutamic acid, glycine and lysine. Based on the polyphasic analyses, strains zg-332T (=KACC 22128T=GDMCC 1.1729T) and ZJ293 represent a novel genus and species within the family Actinomycetaceae, for which the name Tongtianella jiaweipingae gen. nov., sp. nov. is proposed; strains ZJ405T (=GDMCC 1.1953T=KACC 22129T) and ZJ1691 represent a novel species of the genus Schaalia, for which the name Schaalia zhouxuedongae sp. nov. is proposed.

BackgroundPerturbations of the gut microbiota in pulmonary tuberculosis (PTB) patients, often antibiotic-induced, are frequently observed; however, the defining features of this dysbiosis and its relationship with clinical phenotypes remain insufficiently characterized.MethodsIn this cross-sectional study, we collected fecal samples from 66 PTB patients and performed 16S rRNA gene (V3-V4) sequencing. Species-level taxonomic profiling was conducted using the Human Gut Microbiome Analysis Database (HGMAD). Enterotypes were constructed, and their associations with PTB were investigated. The predictive capacity of enterotype-specific microbial signatures (enterosignatures) for clinical phenotypes was assessed.ResultsTaxonomic analysis revealed significantly reduced prevalence of high-abundance bacteria group in PTB patients (43.84%) compared to healthy controls (HC, 98.01%), indicating increased microbiota heterogeneity. Known pathogenic species, predominantly common respiratory opportunistic pathogens (e.g., Haemophilus parainfluenzae, Acinetobacter baumannii, Veillonella parvula), were more prevalent in the PTB cohort (21.37% vs. 11.49% in HC). Enterotype analysis revealed a distinct cluster, designated ETE (Enterobacterales-dominated enterotype), which was predominantly observed in PTB patients and differed from the conventional Prevotella-dominated enterotype (ETP) and Bacteroides-dominated enterotype (ETB), identified in HC. ETE was significantly enriched in taxa including Acinetobacter baumannii, Enterococcus, Veillonella, Pseudomonas, and Streptococcus, exhibited lower alpha diversity, and functional inference using PICRUSt2 suggested relative lower immune-related pathways. Clinically, ETE was associated with lower cellular immunity and a trend toward higher C-reactive protein (CRP) levels. A model based on ten super-dominant respiratory pathobionts enterosignatures effectively predicted key clinical phenotypes, with area under the curves (AUCs) of 0.83 for CD4+ T-cell count, 0.74 for CD8+ T-cell count, 0.74 for CD4+/CD8+ ratio, 0.93 for CRP, 0.78 for CA125, and 0.70 for Mtb positivity. SHapley Additive exPlanation (SHAP) analysis identified Enterobacterales and Veillonella as key negative predictors for T-cell counts, while Streptococcus and Enterobacteriaceae were positive predictors for CRP. In the CA125 model, Veillonella acted as a positive predictor and Enterobacterales as a negative predictor.ConclusionThis cross-sectional study identifies a distinct, PTB-associated enterotype (ETE) characterized by enrichment of respiratory pathobionts and associated with altered immune parameters in PTB patients. Enterosignatures derive from ETE represent exploratory biomarkers with promising predictive capacity for clinical outcomes, though their generalizability warrants validation in independent, prospective cohorts.

Ticks are important vectors of bacterial pathogens with veterinary and public health significance. However, information on the diversity of tick-associated bacteria in forest ecosystems of northeastern China remains limited. In this study, 821 questing ticks were collected from Huoshankou National Forest Park in Mudanjiang City, Heilongjiang Province, and identified as Haemaphysalis japonica, Hae. concinna, and Ixodes persulcatus. Molecular screening based on rrs gene amplification detected Anaplasma, Ehrlichia, and Coxiella-like endosymbionts (CLE), which were further characterized using multilocus phylogenetic analyses. Anaplasma bovis was detected in Hae. concinna and exhibited two distinct genotypes. In addition, a potentially novel Anaplasma lineage was identified in I. persulcatus. Phylogenetic analyses based on the rrs, gltA, and groEL genes consistently placed this lineage in a separate clade from currently recognized Anaplasma species. Furthermore, two genetically distinct Ehrlichia lineages were detected in Hae. japonica and Hae. concinna. Two lineages of tick-associated CLE were also characterized using five genetic genes. Overall, these findings demonstrate considerable genetic diversity of tick-associated bacteria in forest ecosystems of northeastern China and expand current understanding of their molecular diversity. Further studies incorporating broader sampling and genome-based analyses will be necessary to clarify their taxonomic status and epidemiological relevance.

Rodents, which account for over 40% of mammalian species and occupy diverse terrestrial ecosystems, are major reservoirs for zoonotic viruses, including Coronaviridae, Hantaviridae, and Arenaviridae. However, the rodent species acting as central hubs for viral diversity and transmission remain poorly defined. To address this, we conducted systematic sampling across 18 counties and cities on Hainan Island between 2023 and 2024. A total of 2550 animals were collected, representing 14 Rodentia species, one Erinaceomorpha species, and one Scandentian species. Based on a statistical sampling framework, 1284 individuals were selected to generate 125 pooled gut samples for virome analysis. We identified 527 viral RNA species and recovered 175 complete or near-complete viral genomes. Remarkably, Rattus norvegicus and Rattus tanezumi accounted for 83.9% (442/527) of detected viral species, 68.6% (72/105) of novel viral sequences, and 88.6% (93/105) of cross-species viruses. Eight novel viruses showed recombination signals, seven originating from these two species. Among 13 human pathogenic viruses identified, 12 were detected in Rattus norvegicus and Rattus tanezumi. These findings suggest that these species may function as hub hosts for viral maintenance and spread, emphasizing the value of targeted surveillance to reduce future potential spillover risks.

Six Gram-stain-positive, coccobacilli, non-motile, oxidase-negative, catalase-positive strains, designated HY-051T, HY049, HY190T, HY1757, HY647T and HY359, were isolated from the faeces of Tibetan wild asses (Equus kiang) in Tibet, China, and from fruit bat (Rousettus leschenaultii) faeces in Yunnan, China. All strains are strictly aerobic. Optimal growth for all strains occurred at 28.0 °C, pH 7.0 and with 1.0% (w/v) NaCl. While 16S rRNA gene analysis confirmed their placement within the genus Rhodococcus, phylogenomic analyses revealed that strains HY-051T/HY049, HY190T/HY1757 and HY647T/HY359 represent distinct lineages. Notably, the digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between these strains and their closest relatives were well below the species delineation thresholds (70% dDDH and 95-96% ANI). Chemotaxonomically, all three groups differ from their closest phylogenetic neighbours by the absence of C15 : 0 and C16 : 1 fatty acids and the presence of Summed Feature 3. Additionally, distinct whole-cell sugar patterns (ribose/arabinose or glucose/galactose), differential menaquinone profiles and API ZYM and 50CH biochemical profiles (e.g. aesculin hydrolysis and carbohydrate utilization) further distinguish them from known species. Based on polyphasic taxonomic analyses, strains HY-051T and HY049 constitute a novel species of the genus Rhodococcus, for which the name Rhodococcus huquni sp. nov. is proposed, with strain HY-051T (=JCM 34841T=CGMCC 1.19145T) as the type strain; strains HY190T and HY1757 constitute a novel species of the genus Rhodococcus, for which the name Rhodococcus quanlei sp. nov. is proposed, with strain HY190T (=JCM 34842T=CGMCC 1.19375T) as the type strain; and strains HY647T and HY359 constitute a novel species of the genus Rhodococcus, for which the name Rhodococcus ruitaii sp. nov. is proposed, with strain HY647T (=JCM 34787T=CGMCC 1.19150T) as the type strain.

Lower respiratory infections (LRIs) are the foremost cause of infection-related mortality worldwide. However, the specific aetiological agents responsible for high hospitalisation rates and elevated coinfection risks across different populations have not been systematically investigated, primarily constrained by clinical practices that often target few pathogens and employ inconsistent testing methods across hospitals. Here, we collected 695,142 bronchoalveolar lavage fluid (BALF) samples from patients hospitalised with LRIs across 4758 hospitals of Chinese mainland between January 2022 and May 2025 and analysed 28 common respiratory pathogens using targeted next-generation sequencing (tNGS). Based on the real-world pathogen spectrum, we stratified the hospitalised patients undergoing BALF sampling into eight distinct age groups, corresponding to eight life-stages, and established life-stage-specific patterns of pathogen distribution. Subsequently, we identified 124 coinfecting pathogen pairs and three characteristic co-detection networks. 79.03% of observed co-detections occurred within these networks. Furthermore, our analysis revealed that bacteria and fungi such as KPN, PJ, and ABA were more frequently detected in hospitalised male patients, which indicates sex-specific differences in detection patterns. We also observed that males aged 0-4 years and 35+ years were more frequently represented among hospitalised patients with severe LRIs. These findings may inform age- and sex- stratified infectious disease prevention, control, and clinical management. Specifically, they may support public health practitioners in optimizing vaccination strategies; assist diagnostic developers in creating life-stage-specific diagnostic panels that prioritize commonly detected pathogens; and aid clinicians in assessing patterns of hospitalisation and co-detection based on nationwide data from BALF-sampled hospitalised LRI cases.

Shrews represent an important reservoir of diverse human-pathogen viruses with implications for human infectious diseases. As the most populous shrew species, the Asian house shrew-Suncus murinus (Su. murinus) is widely distributed across South and Southeast Asia-particularly tropical and subtropical regions-yet its virome remains poorly studied. In this study, we collected 249 Su. murinus from 18 cities/counties (excluding Sansha) across Hainan Island and conducted RNA sequencing on gut, spleen, and lung tissues. We identified 192 RNA viruses, comprising 120 known viral species and 72 novel viruses, including key zoonotic viral families: Arenaviridae, Hantaviridae, Paramyxoviridae etc. We assembled 102 complete and nearly complete genomes. Notably, 64 known viruses exhibited cross-species transmission potential, including 57 with spillover risk and 7 human-pathogenic viruses: Mammarenavirus choriomeningitidis (LCMV), Henipavirus (HeV), Wenzhou virus (WENV), Langat virus (LGTV), Amur virus (AMRV), Influenza A virus (H1N1), and Rotavirus A (RVA). Additionally, AMRV, LGTV, and LCMV were reported here for the first time in Su. murinus based on metagenomic detection. Our phylogenetic and RT-PCR results indicate Su. murinus is a candidate reservoir for Langya-like henipavirus. Collectively, our study reveals tropical populations of Su. murinus are a previously underappreciated reservoir of viral diversity, underscoring their key role in zoonotic emergence and necessitating surveillance in tropical regions.

Southwest China is a global biodiversity hotspot, and its complex and diverse ecosystems harbor vast amounts of “microbial dark matter.” This paper systematically examines the distribution characteristics of microbial dark matter in hosts such as arthropods, mammals, and birds, as well as in environments including soil, hot springs, and high-altitude lakes, with a particular focus on the cross-species transmissibility and pathogenic potential of emerging pathogens. Research indicates that new microbial species in the Southwest exhibit significant geographic concentration and host specificity: Yunnan Province is a core hotspot, while the Tibet Autonomous Region contributes a wealth of microbial resources due to its extreme environments, with arthropods and mammals accounting for the highest proportion of novel species. Regarding public health risks, eight novel pathogens with evidence of human infection have been identified, spanning the three major groups of viruses, bacteria, and parasites. The cross-species transmission potential of some pathogens (such as DPRV rhabdovirus, PPV arenaviridae, Luxi hantavirus, Banna virus and a novel Babesia species) has been confirmed through serological surveys or molecular testing. Deepening the exploration of microbial dark matter and risk early warning in this region will provide critical scientific support for public health safety monitoring.

The northeastern region of China is characterized by complex ecosystems, including forests and wetlands, and borders North Korea, Russia, and Mongolia. It serves not only as a natural reservoir for various microorganisms but also as a critical geographical and ecological hub for cross-border exchanges in Northeast Asia. Based on metagenomics and meta-transcriptomics investigations, this study systematically reviews the current research status of novel pathogens in the northeastern border region of China. It systematically organizes the newly discovered species, their classifications, and geographical distributions, with a focus on analyzing novel viruses that have potential pathogenicity to humans. The novel viruses identified in the northeastern border region belong to 11 viral families, including 9 from the Nairoviridae, 4 from the Rhabdoviridae, 3 each from the Astroviridae, Picornaviridae, and Parvoviridae, and 1-2 from other viral families, indicating a broad diversity of newly discovered viruses. These novel viruses are found in a wide range of hosts, including humans, ticks, minks, Marmota sibirica, and Myodes rufocanus, underscoring the significant public health risks these viruses pose. Geographically, the novel viruses discovered in the northeastern border region show a clustering pattern, with new species primarily concentrated in areas bordering Russia and North Korea. This highlights the unique role of the region as a hotspot for cross-border pathogen transmission and risk. The findings provide a systematic scientific reference for understanding the spectrum of unknown novel pathogens and their geographical distribution in the northeastern border region, assessing the risk of emerging infectious diseases, and optimizing active surveillance systems.

Four novel bacterial strains, designated as G56T, G1551, G349T and G368, were isolated from in situ coal samples. All four strains were Gram-stain-positive, catalase-positive, oxidase-negative, non-motile and aerobic. Phylogenetic analysis based on 16S rRNA gene sequences revealed that G56T and G1551 represented the same species, and that G349T and G368 represented another species, with both species falling within the genus Janibacter. Strains G56T and G1551 exhibited the highest 16S rRNA gene sequence similarity to Janibacter anophelis CCUG 49715T (98.61%), whereas strains G349T and G368 exhibited the highest 16S rRNA gene sequence similarity to Janibacter limosus DSM 11140T and Janibacter terrae NBRC 107853T (99.03-99.10%). The average nucleotide identity and digital DNA-DNA hybridization values between the proposed type strains (G56T and G349T) and species of the genus Janibacter were 74.59-89.54% and 19.70-38.30%, respectively. The DNA G+C contents of G56T and G349T were 71.0 and 71.5 mol%, respectively, and both strains contained only menaquinone MK-8(H4) as the respiratory quinone. The major cellular fatty acids of strain G56T were C16:0 10-methyl and/or iso-C17:1  ω9c, iso-C17:0 and iso-C15:0, whereas those of strain G349T were C18:1  ω9c, iso-C16:0 and C17:1  ω8c. The polar lipid profiles of both strains comprised diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol, and meso-diaminopimelic acid was identified as the diagnostic diamino acid in the cell wall. Based on phenotypic, phylogenetic and chemotaxonomic evidence, strains G56T and G349T were considered to represent two novel species of the genus Janibacter, for which the names Janibacter zhaoxuefangae sp. nov. and Janibacter zhangyanbonis sp. nov. are proposed. The type strains are G56T (=GDMCC 1.5581T=JCM 37886T) and G349T (=GDMCC 1.5549T=JCM 37887T).

Four Gram-stain-negative, non-spore-forming, motile, short rod-shaped strains (LY29T, LY160, LY54T and LY1275) were isolated from soil of the Qinghai-Tibetan Plateau, China. Based on 16S rRNA gene sequences, strain pairs LY29T/LY160 and LY54T/LY1275 were identified as members of the genera Sphingomonas and Sphingosinicella, respectively, with highest similarities to Sphingomonas alba SE158T (97.8%) and Sphingomonas montis DRJ-4T (98.0%), respectively. In phylogenomic analyses based on 426 core gene sequences, LY29T and LY160 clustered with Sphingomonas rhizophila THG-T61T, while LY54T and LY1275 were closely related to Sphingosinicella humi QZX222T, Sphingosinicella flava UDD2T and Sphingosinicella vermicomposti KCTC 22446T. Digital DNA-DNA hybridization and average nucleotide identity values between the four strains and their closest relatives were determined to be below 24.2% and 80.49%, respectively, thus falling below the recommended species delineation thresholds (70% and 95-96%, respectively). The genomic DNA G+C contents of strains LY29T and LY54T were 64.8 and 66.8 mol%, respectively. Strain LY29T contained predominant fatty acids C16 (C16:1  ω7c and C16:1  ω6c) and C18 (C18:1  ω7c and C18:1  ω6c), while LY54T had iso-C16:0 as the major fatty acid. Both strains shared major polar lipids (diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified sphingoglycolipid). Strain LY29T possessed ubiquinone Q-10 and homospermidine, whereas LY54T contained MK-9(H2) as the major quinone. Based on a polyphasic taxonomic approach, type strains LY29T (=GDMCC 1.4177T=JCM 36472T) and LY54T (=GDMCC 1.4236T=KCTC 8630T) represent novel species of the genera Sphingomonas and Sphingosinicella, for which the names Sphingomonas lindongxini sp. nov. and Sphingosinicella wutangchuni sp. nov. are proposed.

Klebsiella pneumoniae (KP) is an important opportunistic pathogen that can persist in the gastrointestinal tract and serve as a reservoir for subsequent infection. The increasing prevalence of multidrug-resistant KP highlights the need for non-antibiotic strategies to limit intestinal KP burden and associated host injury. Lactiplantibacillus plantarum GUANKE (L. plantarum GUANKE) is a candidate probiotic strain with reported effects on mucosal barrier protection and inflammatory regulation, but its role in intestinal KP challenge remains unclear. In this study, the effects of L. plantarum GUANKE and its metabolite phenyllactic acid (PLA) on KP growth, intestinal KP burden, and associated inflammatory injury were investigated using antibacterial assays in vitro, metabolomic analyses, an antibiotic-pretreated mouse model of intestinal KP challenge, and an influenza A virus (IAV)/KP intestinal co-exposure model. L. plantarum GUANKE and its culture-derived products inhibited KP growth in vitro. Metabolomic analysis identified PLA as a metabolite enriched in L. plantarum GUANKE fermentation supernatants, and exogenous PLA directly inhibited KP growth in a dose-dependent manner. In an antibiotic-pretreated mouse model of intestinal KP challenge, oral administration of L. plantarum GUANKE reduced intestinal KP burden and was associated with changes in gut microbiota composition, increased cecal PLA abundance, improved intestinal barrier-related parameters, and reduced inflammatory responses, while exogenous PLA partially reproduced these effects. IAV infection increased susceptibility to intestinal KP expansion, and oral L. plantarum GUANKE reduced KP burden in the IAV/KP intestinal co-exposure model. In mice challenged with multidrug-resistant KP strain NK04152, L. plantarum GUANKE and PLA reduce intestinal KP burden and associated tissue injury in mice, supporting their potential as candidate microbiota and metabolite strategies against intestinal KP challenge.

Two Gram-stain-positive, catalase-positive, oxidase-negative, non-spore-forming, aerotolerant anaerobic and non-motile short rod-shaped bacterial strains, designated V947T and V970, were isolated from nasal swab samples of coal miners. Phylogenetic analyses based on 16S rRNA gene sequences and whole-genome sequences revealed that strains V947T and V970 represent a distinct lineage within the genus Cutibacterium, most closely related to Cutibacterium avidum ATCC 25577T (16S rRNA gene sequence similarity of 97.09%). Whole-genome comparative analyses showed that the average nucleotide identity values between the two strains and all validly published species of the genus Cutibacterium with correct nomenclature ranged from 76.55 to 90.26%, while the digital DNA-DNA hybridization values ranged from 21.80 to 40.40%, both of which are well below the accepted thresholds for species delineation. Pangenome analysis identified 711 species-specific gene clusters present in strains V947T and V970 but absent from all reference type strains of the genus, which were predominantly involved in carbohydrate transport and metabolism, inorganic ion transport and signal transduction mechanisms, suggesting distinct metabolic capabilities and potential for environmental adaptation. These genomic features not only support the delineation of a novel species but also expand the known genomic and functional diversity within the genus Cutibacterium. The predominant cellular fatty acids were iso-C15:0 and anteiso-C15:0. The major polar lipids of strain V947T were diphosphatidylglycerol, phosphatidylinositol and phosphatidylcholine, and the predominant menaquinones were MK-8(H4) and MK-9(H6). On the basis of phylogenetic, genomic, chemotaxonomic and phenotypic characteristics, strains V947T and V970 represent a novel species of the genus Cutibacterium, for which the name Cutibacterium nasicola sp. nov. is proposed. The type strain is V947T (=CGMCC 1.5844T=KCTC 59608T).

Background/Objectives: To investigate the antagonistic effect of probiotic Lactiplantibacillus plantarum GUANKE against respiratory syncytial virus (RSV) and its underlying molecular mechanisms. Methods: in vitro cell models (A549 and HEp2 cells) and an in vivo mouse model (BALB/c mice) were employed. RT-qPCR, TCID50 assay, immunofluorescence, ELISA, Western blot, and histopathological analysis were used to investigate the effects of GUANKE on RSV replication, inflammatory responses, and the type I interferon pathway. Results: Oral administration of GUANKE effectively cleared RSV and alleviated RSV-induced pulmonary inflammatory responses. GUANKE inhibited viral replication. The GUANKE intervention group exhibited significantly reduced pathological damage to lung tissue and decreased the expression of inflammatory cytokines (IL-1β, IL-6, MCP-1, TNF-α). GUANKE augmented the early type I interferon response and activated the STING-TBK1-IRF3-IFN signaling pathway. Conclusions: GUANKE exerts anti-RSV effects by enhancing the early type I interferon response and activating the STING-TBK1-IRF3-IFN signaling pathway, thereby inhibiting RSV replication and alleviating pulmonary inflammatory responses. This suggests its potential value as an anti-RSV agent.

Four Gram-stain-positive, catalase-negative, oxidase-negative, strictly anaerobic, non-spore-forming, non-motile, coccoid bacteria (G1425T/G1967 and G1604T/G1641) were isolated from the pharyngeal swabs of coal miners in Shanxi Province of China. Phylogenetic analysis of the 16S rRNA gene and 194 core genes revealed that these 4 strains belong to the genus Parvimonas. These strains were most closely related to Parvimonas micra ATCC 33270T and Parvimonas parva S3374T. Average nucleotide identity (84.0-90.9%) and digital DNA-DNA hybridization values (27.3-42.0%) were below the species-level thresholds. The major fatty acids of all four strains were C16:0, C18:1  ω9c and C18:0. Major polar lipids were composed of diphosphatidylglycerol and phosphatidylethanolamine. Ubiquinone-8 was the sole ubiquinone detected in strains G1425ᵀ and G1604ᵀ. Based on phenotypic and phylogenetic evidence, we propose that strains G1425T and G1604T represent two novel species of the genus Parvimonas, respectively, with the names Parvimonas oralis sp. nov. and Parvimonas pharyngis sp. nov. The type strains are G1425T (=GDMCC 1.5468T=JCM 37774T) and G1604T (=GDMCC1.5469T=JCM 37775T).

Streptococcus parasuis is an emerging zoonotic pathogen responsible for pneumonia, meningitis, peritonitis, pleuritis, nephritis, cellulitis, cholecystitis, sepsis, and arthritis in humans. The continuous increase in reported human cases of S. parasuis infection indicates its growing threat to public health and highlights the urgent need to monitor its epidemiology. The lack of high-throughput typing tools has seriously impeded the epidemiological surveillance of S. parasuis. Serotyping based on antigenic differences in capsular polysaccharides (CPSs) synthesized by cps loci is widely applied in epidemiological research and routine surveillance of various pathogens. In this study, the genetic characteristics of cps loci extracted from 259 S. parasuis genomes isolated from multiple sources were investigated. Among the 259 S. parasuis genomes, 142 genomes contained an intact cps locus, while the cps loci of 117 genomes were incomplete due to the limited length of the contigs. The intact cps loci were predominantly located between the flanking genes SSU1210 and SSU1209. The presence of wzy genes in all cps loci suggests that CPSs are synthesized via the Wzx/Wzy pathway in S. parasuis population. Based on sequence alignment of the wzy genes, 109 putative serotypes were identified, 10 of which were associated with human infection. The products of the 2047 cps genes from these 109 putative serotypes were grouped into 870 homology groups, of which 79.66

This study, which demonstrates that the single-population Susceptible-Exposed-Infectious-Recovered (SEIR) model is also applicable to the assessment and prediction of vector-borne infectious disease outbreaks, provides a reliable model tool for the future prevention and control of vector-borne unknown (X) epidemics. One of the key contributions is the identification of a suitable interpretation of the model parameters. The EpiSIX prediction system, via application of a single SEIR model, was used to fit and analyse the 2025 Foshan City chikungunya fever epidemic data and the 2024-2025 dengue fever epidemics data from Guangdong Province. The results showed that the average serial interval of both fevers was approximately 11 days. The estimated basic reproduction number (R0) was around 6.0 for the chikungunya fever epidemic in Foshan City and approximately 4.0 and 3.0 for the 2024 and 2025 dengue fever epidemics in Guangdong Province, respectively. An additional prediction of the development trend of the ongoing 2025 dengue fever epidemic in Guangdong Province indicated that the final number of infections would range between 3400 and 6000 cases. Finally, a comparison between the uncontrolled developments of the omicron epidemic (with an average serial interval of 4 days) and the chikungunya fever epidemic (with an average serial interval of 11 days, 2.75 times that of omicron) under the same R0 value (5.60) showed that the omicron epidemic would last for 50 days, while the chikungunya fever epidemic would persist for 120 days. Theoretically, the pressure of the former on medical resources would be 2.5 times that of the latter. (c) 2026 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Influenza A virus (IAV) remains a major global threat, highlighting the need for host-targeted antiviral strategies. While some probiotics offer prophylactic protection, their therapeutic potential post-infection is poorly understood. Here, we investigated human-derived Lactobacillus brevis ZG2488 for its antiviral potential against IAV. Strikingly, a more pronounced reduction in viral titer was observed when live bacteria were administered therapeutically post-infection, compared to preventive pretreatment. Transcriptomic analysis suggested that the therapeutic effect of viable bacteria was associated with a modulated host response, including the downregulation of specific host factors implicated in viral replication (e.g., KPNA2, NUP98, EIF2S1) and a delayed interferon-beta (IFNB1) induction. In contrast, preventive effects appeared to be mediated by heat-stable components. These findings highlight a viability-dependent mode of action for L. brevis ZG2488 and contribute to the growing evidence that certain probiotics may exert antiviral effects through targeted host modulation rather than solely through broad immune activation.