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Timing of OMERACT core domain measurement in gout clinical trials: a systematic review of randomised trials.

AIMS: The Outcome Measures in Rheumatology (OMERACT) initiative has endorsed core domain sets for gout trials. The aims of this study were to evaluate the time points and frequencies at which the gout core domains are measured in existing gout urate-lowering therapy and gout flare trials, and whether all collected measurements were reported. METHODS: Urate-lowering therapy (n = 29) and gout flare randomised clinical trials (n = 14) from 2005 were identified from a prior systematic review of core domain reporting. Data were extracted for the time points and frequencies at which each core domain was measured, as well as whether all collected measurements were reported. RESULTS: In urate-lowering therapy trials, the core domains were measured at seven different frequencies. Serum urate and gout flares were most commonly measured monthly, and tophus burden was most commonly measured three monthly. Reporting of all collected measurements varied, from 24/29 (83%) trials for serum urate to 0/2 (0%) trials for activity limitation. In gout flare trials, core domains were measured at nine different frequencies. Pain, joint tenderness and joint swelling were most commonly measured monthly. Reporting of all collected measurements varied, from 13/14 (93%) trials for pain to 3/8 (37.5%) trials for joint tenderness. CONCLUSION: In both urate-lowering therapy and gout flare trials, there is substantial variability in when the core domains are measured, and reporting of collected measurements is inconsistent. This work provides the foundation for a consensus process to establish standardised time points and frequencies for measuring the OMERACT-endorsed gout core domains.

Gout

Definition and prevalence of residual disease in inflammatory arthritis: a systematic literature review and meta-analysis.

OBJECTIVE: To assess how residual disease (i.e., clinically relevant signs/symptoms despite achieving treatment targets) is defined in rheumatoid arthritis (RA), psoriatic arthritis (PsA) or axial spondyloarthritis (axSpA), and estimate the prevalence/severity of residual disease in these diseases. METHODS: Systematic review of original research in RA/PsA/axSpA. Two key residual disease components were extracted: (1) the patient's disease state (often remission/low disease activity) and (2) which residual signs/symptoms were measured, e.g. swollen joints or fatigue (indicators of residual disease). Frequencies of the disease states and indicators were described (Objective 1). Prevalence (%) and severity (absolute score on instrument, e.g. fatigue NRS) of residual disease was analysed by indicator, using random effects meta-analysis (&#x2265;4 studies) or descriptively (<4 studies) (Objective 2). RESULTS: Regarding residual disease definitions (59 studies), disease states were almost exclusively disease activity-based (>99%), but with much variation in specific instruments/thresholds. Across diseases, physician-reported (66%) and patient-reported (73%) indicators were used more often than laboratory indicators to define residual disease (46%). Especially peripheral joint counts, pain, physical function and CRP were frequently used (42-56% of studies). The prevalence of residual disease (84 studies) was notable. For example, 5-25% of RA and PsA patients in remission still had swollen joints, and up to one-third reported relevant pain or fatigue. For axSpA, evidence was limited. CONCLUSION: Residual disease definitions in RA/PsA/axSpA are based on various disease activity instruments/thresholds and indicators (signs/symptoms). Residual disease affects up to half of patients. Future research should aim for a consensus-based definition of residual disease.

Humans

Test-retest reliability of spatiotemporal, kinematic, and kinetic measures in marker-based 3D gait analysis: A systematic review.

BACKGROUND: Marker-based 3D gait analysis (3DGA) is widely used to quantify impairments and evaluate treatment effects. For longitudinal clinical interpretation, clinicians and researchers need reference values for inter-session measurement error. For this purpose, this systematic review synthesized Standard Error of Measurement (SEM) values for spatiotemporal, kinematic, and kinetic (moments) outcomes obtained from marker-based 3DGA studies. METHODS: PubMed and Scopus were searched (final search: 11 December 2025). Studies reporting inter-session test-retest SEM and/or MDC for steady-state overground or treadmill walking using marker-based motion capture were included. Two authors screened records and appraised methodological/reporting quality using a custom tool informed by COSMIN, GRRAS, and biomechanics-specific items. Due to heterogeneity, results were synthesized descriptively using study-level median SEM values, stratified by joint, plane, population (healthy, pathological, single subgroups), and walking condition. Minimal Detectable Change (MDC) values were computed for all available data. RESULTS: Thirty-four studies (762 participants, 44.2% females) were included, with substantially more evidence for overground than treadmill walking. Overground spatiotemporal outcomes showed low errors (walking speed SEM of 0.06 m/s; timing typically &#x2264;0.03 s; spatial parameters generally &#x2264;0.03 m). For joint kinematics during overground walking, median SEMs were 2.4&#xb0; (sagittal), 1.9&#xb0; (frontal), and 3.3&#xb0; (transverse). The corresponding joint-kinetic SEMs were approximately 0.06, 0.04, and 0.03 Nm/kg, respectively. Treadmill data followed similar patterns. SIGNIFICANCE: Marker-based 3DGA allows for accurate assessment of spatiotemporal, kinematic, and kinetic gait features. We provided detailed SEM/MDC lookup tables to support clinical decision-making. Results further offer a benchmark for validating emerging gait assessment technologies (e.g., markerless systems) against realistic limits of marker-based 3DGA.

Humans

Integrative multi-omics reveals a fibroblast-centered, ZFHX3-prioritized regulatory framework linking sick sinus syndrome and atrial fibrillation.

OBJECTIVE: To define shared genetic and multi-scale mechanisms underlying comorbidity between sick sinus syndrome (SSS) and atrial fibrillation (AF). METHODS: We integrated genome-wide association study (GWAS) summary statistics for SSS and AF with Genotype-Tissue Expression (GTEx) expression and splicing quantitative trait loci (eQTL/sQTL), atrial single-cell and spatial transcriptomics, and epigenomics. We identified trait-relevant tissues and pathways, prioritized shared cell types, quantified genome-wide and local genetic sharing, detected joint loci by cross-trait meta-analysis, and linked loci to regulatory programs via colocalization and cell-prioritized co-expression networks. RESULTS: Both traits showed strongest enrichment in cardiac tissue, especially Heart Atrial Appendage. Fibroblasts from the left atrial appendage were consistently prioritized as the key shared cell population. SSS and AF displayed significant positive genome-wide genetic correlation, with multiple locally shared regions, including six major loci. Cross-trait meta-analysis identified eight joint-phenotype SNPs implicating four susceptibility genes. ZFHX3 was the leading tissue-cell-gene candidate, acting as a hub in fibroblast co-expression modules and colocalizing with cardiac regulatory signals. CONCLUSION: Shared liability for SSS and AF is highly tissue- and cell-specific, converging on regulatory networks in atrial appendage fibroblasts, with ZFHX3 serving as a central mechanistic and biomarker node.

Humans

Effects of different resistance exercise programs on upper limb functional recovery in postoperative breast cancer patients.

PURPOSE: To investigate the effects of grip strength exercise combined with upper limb resistance exercise on upper limb functional rehabilitation in patients after breast cancer surgery. METHODS: A total of 111 patients who underwent either modified radical mastectomy with ALND or breast-conserving surgery with ALND were randomly assigned to a control group, an upper limb resistance exercise group, and a combined grip and upper limb resistance exercise group. Grip strength was measured at baseline, 16 weeks after intervention, and at 3- and 6-month follow-ups, while shoulder function was assessed using the Constant-Murley Scale (CMS). RESULTS: There were no statistically significant differences in grip strength or CMS scores among the groups before intervention (P&#x202f;>&#x202f;0.05). At the post-intervention, 3-month, and 6-month follow-ups, compared with the control group, both resistance training protocols significantly improved patients' joint range of motion, pain, muscle strength, total CMS score, and grip strength (P&#x202f;<&#x202f;0.05). Compared with the upper limb resistance exercise group, the combined grip and upper limb resistance exercise group demonstrated superior grip strength at the 6-month follow-up (P&#x202f;<&#x202f;0.05), as well as more significant improvements in joint range of motion, pain, muscle strength, and total CMS scores (P&#x202f;<&#x202f;0.05). CONCLUSION: A 16-week resistance exercise program effectively improves upper limb function in post-surgical breast cancer patients, with the combined grip and upper limb resistance exercise program yielding superior outcomes.

Humans

Effectiveness of chlorhexidine gluconate-impregnated dressings in preventing central line-associated bloodstream infection in a paediatric intensive care unit: A randomised controlled trial.

OBJECTIVES: To compare the effectiveness and dermatological safety of chlorhexidine gluconate (CHG)-impregnated dressings versus conventional transparent dressings in preventing central line-associated bloodstream infection (CLABSI) in paediatric patients admitted to a PICU. METHODS: A single-blind, randomised controlled trial with a 1:1 allocation ratio was conducted in a tertiary PICU. A total of 250 paediatric patients with a central venous catheter were included (125 per group). Patient characteristics, catheter-related variables, catheter dwell time and skin alterations were recorded. The primary outcome was CLABSI, defined according to CDC/NHSN criteria. Bivariate analyses and multivariable logistic regression were performed, including clinically relevant covariates related to catheter exposure, dressing type, and vaccination status. The trial was registered at ClinicalTrials.gov (NCT07175116). RESULTS: CLABSI incidence was significantly lower in the CHG group compared with the conventional dressing group (2.4% vs. 18.4%; p&#xa0;<&#xa0;0.001). In multivariable analysis, CHG-impregnated dressings were independently associated with reduced CLABSI risk (OR = 0.15; 95% CI: 0.04-0.58). Longer catheter dwell time (OR = 1.13 per day; 95% CI: 1.04-1.22) and absence of complete vaccination (OR = 8.68; 95% CI: 2.48-30.47) were also associated with increased infection risk. Incomplete vaccination showed a similar trend without reaching statistical significance (OR = 6.48; 95% CI: 0.95-44.20). Skin alterations were more frequent in the CHG group (16.8% vs. 11.2%), predominantly in younger infants. CONCLUSIONS: CHG-impregnated dressings were associated with a significant reduction in CLABSI incidence in critically ill paediatric patients, although their use was linked to a modest increase in mild skin reactions. IMPLICATIONS FOR CLINICAL PRACTICE: CHG-impregnated dressings may be considered as part of a multifaceted infection prevention strategy, alongside appropriate catheter management, minimisation of catheter manipulation and proactive skin monitoring, with cautious and individualised use in infants.

Humans

Genomic epidemiology of clinically critical antibiotic resistance in Salmonella enterica causing bloodstream infections across six Chinese provinces, 1994-2023.

Clinically critical antibiotic-resistant Salmonella enterica (S. enterica) causing bloodstream infections remains a public health challenge. Here, we aim to reveal the emergence and trends of clinically important antibiotic resistance in S. enterica causing bloodstream infections using 833 isolates from six Chinese provincial-level administrative areas during 1994-2023. We identified 48 serovars and 64 sequence types (STs). Overall, 8.52% of 833 isolates were resistant or had decreased susceptibility to ciprofloxacin, 4.32% and 6.84% reported resistance or decreased susceptibility to third- and fourth-generation cephalosporins (3GCs and 4GCs), 1.80% reported resistance to fosfomycin, and 2.16% reported resistance to azithromycin. Across these six regions, azithromycin and fosfomycin resistance is increasing, as is decreased susceptibility or resistance to ciprofloxacin, 3GCs, and 4GCs, especially among younger children and elderly people. Clinically prioritized antibiotic resistance also varies by region, serovar, and age group. S. Paratyphi A genotype 2.3.3 strains are mainly divided into 2 lineages distributed in Guangxi and Shanghai. Within the scope of this passive surveillance dataset, S. Typhi genotype 4.3.1.2.1 was identified as the earliest documented case among the collected isolates. Our retrospective and longitudinal genomic epidemiology study provides critical data for the formulation of treatment guidelines and policies for bloodstream infections and for the monitoring and control of antimicrobial resistance.

Humans

Transcriptomic analysis provides molecular insights into the innate immune defense of Mactra veneriformis against Vibrio alginolyticus infection.

Mactra veneriformis is an economically important bivalve mollusc in China, but its aquaculture is frequently threatened by Vibrio infections, particularly Vibrio alginolyticus. To investigate the molecular immune response of M. veneriformis to V. alginolyticus, we performed RNA-seq analysis of hepatopancreatic tissues collected at 48&#xa0;h post-infection, the peak mortality time point, with PBS-injected individuals used as controls. Infection with V. alginolyticus caused severe histopathological damage in the hepatopancreas and resulted in a cumulative mortality of 53.3% over 14 d, compared with 3.3% in the control group. Transcriptomic analysis identified 2623 differentially expressed genes (DEGs), including 1585 significantly up-regulated genes and 1038 down-regulated genes. KEGG enrichment analysis demonstrated that DEGs were significantly enriched in immune related and metabolism pathways, including the JAK-STAT signaling pathway, RIG-I-like receptor (RLR) signaling pathway, and cytochrome P450 (CYP450) signaling pathway. Collectively, these findings revealed candidate immune related genes (tlr3, tlr5, myd88, nfkb1, il-17d, and ifi44l), a putative TLR-MyD88-NF-&#x3ba;B signaling axis, and KEGG signaling pathways, including JAK-STAT, RLR and CYP450, that may be involved in the innate immune response of M. veneriformis to V. alginolyticus infection. These results provide a transcriptomic basis for understanding host-pathogen interactions in this species and highlight candidate genes and pathways for future functional validation and potential application in disease-resistance breeding.

Animals

Activity of Aztreonam-avibactam and Ceftazidime-Avibactam against Enterobacterales and Pseudomonas aeruginosa causing infections in patients hospitalized in hematology, oncology, and transplant units from United States medical centres (2019-2024).

Immunosuppression increases the risks and severity of infections and is associated with a higher incidence of infection with multidrug-resistant (MDR) pathogens. We evaluated the antimicrobial susceptibility of Enterobacterales and Pseudomonas aeruginosa from patients hospitalized in hospital units where the frequency of immunosuppressed patients is very high. Bacterial isolates were consecutively collected (1/patient) from 75 US medical centres in 2019-2024 and susceptibility tested by broth microdilution. Enterobacterales (n = 2,407) and P. aeruginosa (n = 485) from patients hospitalized in hematology, oncology, and transplant units were evaluated. Carbapenem-resistant Enterobacterales (CRE) were screened for &#x3b2;-lactamases by whole genome sequencing. Enterobacterales were mainly from bloodstream infection (BSI; 53.6%) and urinary tract infection (19.9%) and P. aeruginosa were mainly from BSI (37.9%) and pneumonia (35.0%). Aztreonam-avibactam, ceftazidime-avibactam, and meropenem-vaborbactam were highly active against Enterobacterales (99.9-99.4% susceptible), including MDR isolates (99.6-98.1% susceptible), but only aztreonam-avibactam exhibited good activity against CRE (95.8% susceptible). Ceftolozane-tazobactam showed good activity against Escherichia coli (95.7% S) and Klebsiella pneumoniae (92.8% S), but limited activity against Enterobacter cloacae species complex (75.9% susceptible). All (100.0%) carbapenemase (CBase)-producing CRE isolates were aztreonam-avibactam-susceptible while 77.4% were ceftazidime-avibactam-susceptible and 67.7% were meropenem-vaborbactam-susceptible. The most common CBases were KPC (41.7%), NDM (12.5%), and OXA-48 types (10.4%). Metallo-&#x3b2;-lactamases represented 23.5% of CBases and were identified in 16.7% of CREs. The most active agents against P. aeruginosa were ceftazidime-avibactam (95.7% susceptible), ceftolozane-tazobactam (94.8% susceptible), and tobramycin (91.5% susceptible). Piperacillin-tazobactam and meropenem were active against 81.4% and 82.5% of P. aeruginosa, respectively, and aztreonam-avibactam inhibited 78.6% of P. aeruginosa at &#x2264;8 mg/L.

Humans

Ceftriaxone for methicillin-susceptible Staphylococcus aureus bloodstream infections is associated with increased short-term mortality: a systematic review and meta-analysis.

BACKGROUND: Bloodstream infections (BSIs) by methicillin-susceptible Staphylococcus aureus (MSSA) are a significant cause of morbidity and mortality, traditionally treated with antistaphylococcal penicillins (ASPs) or cefazolin. Ceftriaxone has emerged as an alternative due to its once-daily dosing regimen and favourable safety profile; however, its efficacy compared to the standard of care (SoC) remains controversial. This evidence synthesis aimed to assess the role of ceftriaxone in treating MSSA-BSIs. METHODS: A systematic literature search was conducted in PubMed, Embase, and Scopus up to December 31, 2025 (PROSPERO protocol CRD42024595748). Studies comparing ceftriaxone to ASPs or cefazolin for MSSA-BSIs were included. Primary outcomes were 30-day and 90-day all-cause mortality . Pooled effect sizes with their 95% confidence intervals (CIs), were calculated using random-effects models, odds ratios (ORs) and mean differences (MDs) according to the type of outcome. RESULTS: Eleven studies totalling 2,568 patients were included. Ceftriaxone was associated with significantly increased 30-day mortality (OR 3.33; 95% CI: 2.17-5.10), although differences at 90&#x2009;days were not significant (OR 1.71; 95% CI: 0.75-3.90). No significant differences were noted for clinical success (OR 0.49; 95% CI: 0.19-1.26), microbiological clearance (OR 1.66; 95% CI: 0.73-3.82). Adverse event rates were similar between groups. CONCLUSION: Given the availability of various alternatives and the consistent short-term mortality signal observed, routine use of ceftriaxone for MSSA-BSIs, especially as initial therapy, is not supported by current evidence. Only novel findings from randomized studies may change the place in therapy of the drug in this context.

Humans

How AI-supported intelligent systems support infection prevention and control training in healthcare: A systematic review of educational functions and outcomes.

AIMS: Artificial intelligence (AI)-supported intelligent systems have been increasingly incorporated into infection prevention and control (IPC) education and training, primarily to support the monitoring of observable behaviors and the provision of feedback. However, existing evidence has focused largely on short-term compliance outcomes, with limited synthesis of the educational role of AI-supported intelligent systems in supporting sustained IPC competence. This systematic review examined how AI-supported intelligent systems have been designed and used to support IPC education and training, with a focus on system characteristics, educational functions, and reported outcomes. DESIGN: A systematic literature search was conducted across the PubMed/MEDLINE, Embase, Cochrane, and CINAHL databases. DATA SOURCES: A total of 18 studies met the inclusion criteria. Findings were qualitatively synthesized according to system design characteristics, educational functions, and outcome domains. REVIEW METHODS: Methodological quality was appraised using the Mixed Methods Appraisal Tool. RESULTS: Most AI-supported intelligent systems focused on hand hygiene and relied on fully automated monitoring systems to capture behaviors and provide performance feedback. Educational functions were predominantly limited to performance assessment, automated feedback, and reminders. Outcomes were mainly measured using compliance or performance metrics, whereas sustained behavioral change and decision quality were rarely assessed. CONCLUSIONS: AI-supported intelligent systems have been used primarily to reinforce short-term IPC performance and compliance. However, their current applications for supporting sustained competence over time remain limited. The findings of this review suggest that AI-supported intelligent systems may serve as maintenance-oriented educational support by extending learning beyond initial instruction through repeated practice and feedback. Future research should prioritize outcome measures that capture the durability of performance and decision-making processes to better align AI-supported intelligent systems used in IPC education and training with the educational demands of clinical practice.

Humans

Ventriculostomy-Related Infections by Country-Income Level: A Systematic Review and Bayesian Hierarchical Meta-analysis.

Our objective was to perform a systematic review and meta-analysis of published literature on ventriculostomy-related infection (VRI) and evaluate temporal and global trends. We conducted a systematic review and Bayesian hierarchical random-effects meta-analysis of VRI rates in adults, stratified by country-income level (high-income countries [HIC]; low- or middle-income countries [LMIC]), study design, sample size, enrollment period, VRI intervention, and VRI definition. We identified 159 articles published between 1989 and 2025 that included 523,704 patients with 7293 VRIs. The pooled VRI rate was 8.64% [95% CI: 7.44-9.97], with moderate heterogeneity and good model fit. The leave-one-out sensitivity analysis showed a mean absolute change of 0.06% and a maximum change of 0.2%, indicating robust analysis. Five of the 33 represented countries had VRI rates below the global pooled rate of 8.64%. Four were HICs: Singapore (VRI rate 3.3% [0.8-7]), the United States (VRI rate 4.6% [3.4-5.9]), Germany (VRI rate 6.1% [1.1-18.9]), Norway (8.3% [0.3-68.4]), with 1 LMIC: China (8.5% [5.4-12.4]). VRI was significantly higher in studies using definitions beyond CSF culture alone for VRI (+3.16% [0.11- 6.52]) and in those from Europe (+7.29% [4.62-10.10]) and the Western Pacific (+4.09% [1.55-6.98]). No other subgroup demonstrated significant differences. This Bayesian meta-analysis provides global estimates and factors associated with VRI. Standardization of VRI definitions is critical for future benchmarking of VRI rates.

Humans

From human papillomavirus (HPV) infection to HPV-associated cancers in systemic lupus erythematosus: A systematic review and Meta-analysis.

OBJECTIVE: The current cervix-focused screening paradigm in systemic lupus erythematosus (SLE) may underestimate extra-cervical anogenital cancer risk. This meta-analysis aimed to quantify the risk of human papillomavirus (HPV) infection and HPV-associated cancers in SLE patients. METHODS: A comprehensive search was conducted in PubMed (2010), Embase (2010), and Cochrane Library (2010) to August 8, 2025. Odds Ratios (ORs) and Standardized Incidence Ratios (SIRs) with 95% Confidence Intervals (CIs) were calculated. The study protocol was registered with PROSPERO (CRD420251122192). RESULTS: SLE was associated with significantly increased odds of HPV infection (OR&#xa0;=&#xa0;4.12, 95% CI 2.03, 8.32). We further assessed the risk of HPV-associated malignancies in SLE patients. SLE patients exhibited substantially elevated risks across multiple HPV-associated cancers (SIR&#xa0;=&#xa0;1.90, 95% CI 1.51, 2.38). The risk of cervical cancer was more than doubled (SIR&#xa0;=&#xa0;2.25, 95% CI 1.75, 2.89). Notably, even higher risks were observed for extra-cervical anogenital cancers, namely vulvar/vaginal cancers (SIR&#xa0;=&#xa0;5.60, 95% CI 3.71, 8.43). CONCLUSIONS: SLE is associated with elevated risks of HPV infection and a broad spectrum of HPV-associated cancers. Subgroup analyses suggested that cyclophosphamide use, multiple sexual partners, and Asian populations may constitute higher-risk subgroups. These findings highlight the need for additional prospective evidence to better characterize HPV-associated cancer risks in SLE patients.

Humans

Clinical predictors of severe and fatal respiratory syncytial virus infection in adults and the elderly: A retrospective cohort study.

BACKGROUND: Respiratory syncytial virus (RSV) is increasingly recognized as a cause of severe respiratory illness in adults, especially the elderly and those with comorbidities. However, data on outcomes and risk factors for severe disease in this population remain limited. METHODS: We retrospectively analyzed 123 adult patients diagnosed with RSV infection at a tertiary center in Taiwan from 2015 to 2023. Clinical characteristics, laboratory data, detection of other pathogens, clinical course and outcome were reviewed. Multivariable logistic regression identified risk factors for severe RSV infection, including ICU admission and 30-day mortality. RESULTS: The mean age was 55.7 years; 50% were aged &#x2265;60 years and 13% were &#x2265;75 years. ICU admission occurred in 17%, with significant associations to viral coinfection and elevated C-reactive protein (CRP). Thirty-day mortality was 13%, and overall in-hospital mortality was 18%, all among patients with comorbidities. Independent predictors of 30-day mortality included late elderly (aOR 24.2, p&#x202f;=&#x202f;0.03), high CRP > 11.5&#x202f;mg/dL (aOR 16.4, p&#x202f;=&#x202f;0.005) and thrombocytopenia < 34,103/&#x3bc;L (aOR 11.4, p&#x202f;=&#x202f;0.01). CONCLUSION: Advanced age (&#x2265;75 years), high CRP, and severe thrombocytopenia are key predictors of mortality in adults RSV patients. These findings highlight the need for targeted prevention strategies, including vaccination, in high-risk populations.

Co-infection

Genomic characterization of a hypervirulent Aeromonas veronii NN0115 from Nile tilapia and head kidney transcriptome of infected fish reveals B-cell-dominated immune response with specific immunoglobulin downregulation.

Aeromonas veronii is a pathogen of multiple fish species, yet systematic understanding of its infection in Nile tilapia (Oreochromis niloticus) remains limited. A dominant strain, NN0115, was isolated from a natural outbreak and identified as A. veronii by 16S rRNA and whole-genome average nucleotide identity (ANI, 96.33%). Experimental infection revealed high virulence (LD50&#x202f;=&#x202f;3.41&#x202f;&#xd7;&#x202f;106&#x202f;CFU/mL, equivalent to 8.53&#x202f;&#xd7;&#x202f;104&#x202f;CFU/fish). The genome is 4.58&#x202f;Mb (58.57% GC) and encodes 4216 proteins. Virulence factor analysis identified 1253 genes, dominated by motility-related (264) and immune modulation (208) factors. Genomic island GI2 harbors 7 virulence genes and two dual-function resistance-virulence genes. The strain is resistant to 9 of 25 agents tested but carries three RND efflux pump genes whose predicted resistance was not phenotypically observed. The head kidney transcriptome of tilapia at 24&#x202f;h post-bacterial infection identified 773 differentially expressed genes; among them, 57 were immunoglobulin (Ig) genes, and 56 were down-regulated. Integration of published single-cell transcriptomic data showed that non-Ig B-cell marker genes were down-regulated by 32%, whereas Ig genes were reduced by 63%, indicating selective transcriptional suppression of Ig genes rather than a general decrease in B-cell transcriptional activity. Together, this study provides a comprehensive characterization of a highly virulent A. veronii from Nile tilapia and reveals that selective downregulation of B-cell Ig genes is the dominant transcriptional feature of the host head kidney response.

Animals

Feeding the disease: The impact of nutritional supplementation on Nosema (Vairimorpha) infection in honey bees (Apis mellifera).

Honey bees (Apis mellifera) experience variable colony losses across regions and years, with infectious diseases representing a key component of colony health challenges. Among the most prevalent pathogens are the microsporidian parasites Nosema apis and Nosema ceranae, whose impacts on host survival and transmission vary widely depending on context. While nutritional supplementation is commonly used to support honey bee health, its effects on Nosema infection outcomes remain unclear. Here, we experimentally tested whether dietary enrichment alters survival and infection intensity following exposure to a mixed Nosema inoculum. Newly emerged worker bees were challenged with Nosema spores and maintained on either a basic sucrose diet or the same diet supplemented with a commercial pollen substitute. Dietary enrichment significantly increased both mortality risk and infection intensity in Nosema-infected bees, while having no detectable effect on survival in uninfected controls. These results indicate that supplementation can, counter intuitively, exacerbate nosemosis by promoting parasite replication rather than enhancing host resistance. Our findings highlight the importance of distinguishing nutritional effects on host tolerance versus resistance, and caution that interventions intended to improve bee nutrition may inadvertently increase pathogen production and transmission potential under certain conditions.

Animals