Adenovirus infections are a leading cause of respiratory and gastrointestinal diseases, representing a significant global health challenge. Rapid and accurate detection of adenovirus types is essential for timely diagnosis and effective management. Traditional diagnostic methods, such as PCR, are often time-consuming and require complex laboratory infrastructure, limiting their application in resource-limited settings. In this study, we present a CRISPR/Cas12a-based assay integrated with a hydrogel microarray for the simultaneous detection of six common adenovirus types (1, 2, 3, 4, 7, and 14). After amplification of adenoviral DNA using recombinase polymerase amplification (RPA), the amplified DNA enters the hydrogel, where it activates the Cas12a-crRNA complex trapped within the gel. This activation leads to the cleavage of an ssDNA reporter, generating a fluorescent signal. The use of a hydrogel microarray enables efficient and multiplexed detection of adenovirus types in a single assay. The method demonstrated high sensitivity, with detection limits ranging from 10 to 50 copies/μL across the six adenovirus types. It also showed excellent specificity, with no cross-reactivity observed with other respiratory viruses. Clinical validation with 30 human adenovirus samples revealed 100% specificity and high concordance with qPCR results. This CRISPR/Cas12a-based hydrogel microarray platform offers a rapid, cost-effective, and highly specific diagnostic tool with significant potential for clinical and public health applications.

Fowl adenovirus serotype 4 (FAdV-4) is a nonenveloped double-stranded DNA virus with a 43-45 kb genome, making it a promising viral vector for developing multivalent poultry vaccines. However, limited genomic studies have hindered the design of strategies for generating recombinant FAdV-4 capable of expressing multiple foreign proteins while maintaining high viral titers. In this study, three deletion mutants (rD14AB, rD2042, rD19A) were generated to assess their roles in viral replication and pathogenicity. Only rD2042 showed impaired replication and virulence compared with wild-type FAdV-4. Foreign gene expression assays demonstrated that the D14AB site had a maximum insertion capacity of 2349 bp, and an SV40 poly(A) signal was required for efficient protein expression and viral propagation at this locus. In contrast, the D19A site tolerated insertions of up to 1257 bp in the absence of this signal. Using the insertion strategy optimized for wild-type CH_JS_2017, we modified the previously reported nonpathogenic rON1 strain (harboring the Hexon gene from the attenuated ON1 strain) to co-express mCherry, eGFP, and mTagBFP2 at the two independent sites. SPF chicken trials verified the safety of the engineered virus at immunization age and the genetic stability of exogenous genes. The recombinant virus maintained wild-type-comparable titers while carrying 3606 bp of total foreign sequences, highlighting its dual-site advantage and potential as a multivalent poultry vaccine vector.

Viral diarrhea remains a significant public health concern in Ghana, particularly among children under 5 years of age. While rotavirus remains the leading cause, the growing impact of other viral pathogens, such as norovirus, adenovirus, and astrovirus, necessitates expanded research and intervention efforts. The introduction of the rotavirus vaccine has significantly reduced diarrhea prevalence, but persistent disparities in disease burden highlight the need for comprehensive control strategies. This scoping review maps the existing evidence on the burden, evolution, and control measures of viral diarrhea in Ghana. A systematic search of PubMed, ScienceDirect, and Scopus was conducted to identify relevant studies published between 1996 and 2025. Findings from local studies indicate that, despite improvements in sanitation, access to potable water, and vaccination programs, viral diarrhea remains widespread and unevenly distributed across populations. The review underscores the importance of enhanced diagnostic capacity, robust surveillance systems, and targeted prevention strategies to effectively combat this public health challenge. By synthesizing available evidence, this scoping review highlights knowledge gaps and priority areas for future research, policy, and intervention in Ghana's fight against viral diarrhea.

Fowl adenovirus serotype 4 (FAdV-4) is the major pathogen responsible for avian hepatitis-hydropericardium syndrome (HHS), which poses a severe threat to the global poultry industry. This study aimed to systematically explore virus-host interactions and elucidate the transcriptomic alterations and underlying molecular mechanisms in LMH cells following FAdV-4 infection. LMH cells were infected with FAdV-4 at a multiplicity of infection (MOI) of 1 for 24 h, and whole-transcriptome sequencing was subsequently performed. Differential expression analysis was conducted between the FAdV-4-infected group and the uninfected Mock group, followed by functional interaction prediction. Quantitative polymerase chain reaction (qPCR) was used to verify the expression profiles of differentially expressed genes (DEGs). The results identified a total of 8292 differentially expressed messenger RNAs (dif-mRNAs), 80 differentially expressed microRNAs (dif-miRNAs), 3263 differentially expressed long non-coding RNAs (dif-lncRNAs), and 52 differentially expressed circular RNAs (dif-circRNAs) in the infected group compared with the Mock group. The identified DEGs were further validated and subjected to Gene Ontology (GO) functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Additionally, protein-protein interaction (PPI) analysis and regulatory network analyses of lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA were performed. This study provides novel insights and research perspectives into the potential mechanisms underlying FAdV-4-host interactions and further deepens the current understanding of the pathogenesis of FAdV-4 infection.

Equine adenovirus type 1 (EAdV-1) infection has been recognised among horses worldwide. The virus predominantly targets respiratory tract but has also been recovered from other body systems. The objective of the study was to determine the frequency of EAdV-1 infection among selected horse populations in Poland and to estimate genetic variability within the viruses obtained. A quantitative PCR assay targeting a partial hexon gene was used to screen 1150 nasal swabs collected from 1145 horses from 19 horse studs throughout Poland. The samples were collected opportunistically between 2012 and 2025. A set of PCR primers was designed to amplify and sequence a partial fibre gene from the qPCR-positive samples. Sequences from 1 to 5 clones from each PCR product were analysed using sequence identity matrix, phylogeny and median-joining haplotype networks. EAdV-1 was found in 49/1150 (4.3%) samples collected from 48 healthy horses and one horse showing clinical signs of respiratory disease. Partial fibre gene sequences from individual horses were closely related to each other. Sequences from each stud were closely related, even if they were collected over several years. Taken together, this study provides first insights into the epidemiology of active infections caused by EAdV-1 among horses from selected Polish studs, including genetic variability among the viruses detected.

Adenoviral infection has been implicated in spontaneous abortion, but the relationship between adenovirus-associated pregnancy loss and systemic apoptotic activation remains incompletely understood. This study investigated serum caspase-3 (CASP3) concentrations and cleaved caspase-3 protein expression in women with adenovirus-associated spontaneous abortion and evaluated the diagnostic performance of serum CASP3. A comparative cross-sectional study was conducted including 90 pregnant women: 46 with adenovirus-associated spontaneous abortion and 44 healthy pregnant controls. Serum CASP3 concentrations were quantified by ELISA, and cleaved caspase-3 expression was evaluated by Western blot in an exploratory sub-cohort. Pearson correlation, multivariable linear regression, and receiver operating characteristic (ROC) analyses were performed. Serum CASP3 was significantly elevated in the spontaneous abortion group relative to controls (5.60 ± 1.21 vs. 2.17 ± 0.49 ng/mL; p < 0.001). Western blot analysis revealed a 28.66 ± 4.80-fold upregulation of cleaved caspase-3 in the abortion cohort (relative expression: 4.30 ± 0.72 vs. 0.15 ± 0.01; p < 0.001). BMI was an independent positive predictor of serum CASP3, whereas hemoglobin demonstrated a significant inverse association. ROC analysis yielded an area under the curve of 0.844 (95% CI: 0.765-0.922), with an optimal diagnostic threshold of 3.45 ng/mL conferring 76.9% sensitivity and 88.6% specificity. Serum CASP3 concentrations and cleaved caspase-3 expression were significantly increased in women with adenovirus-associated spontaneous abortion, supporting an association with enhanced systemic apoptotic activity. Serum CASP3 demonstrated promising discriminatory performance within the study cohort; however, these findings require validation in larger prospective studies before clinical application.

Adenovirus may cause life-threatening infections. While outcomes in immunocompromised patients are well documented, data on critically ill, immunocompetent adults remain limited. To describe the clinical characteristics and outcomes of adenovirus infection in adult intensive care unit (ICU) patients and to identify factors associated with 30-day mortality. This retrospective observational study included adult patients (≥ 16 years) admitted to ICUs between January 2020 and May 2025 with PCR-confirmed adenovirus infection and compatible clinical syndromes, with a primary focus on describing patient characteristics rather than analyzing virological features of the infection. Data were collected from 24 centers in 11 countries. Demographics, comorbidities, clinical characteristics, laboratory findings, treatments, and outcomes were recorded. The primary outcome was 30-day all-cause in-hospital mortality. Variables associated with mortality in univariate analyses were entered into a stepwise multivariable logistic regression model. A total of 126 patients were included; 40 (31.7%) died within 30 days of PCR positivity. The mean age of the entire cohort of patients was 44.9 ± 20.4 years (median 48; 16-95), and 38.9% were female. Pneumonia was the most common presentation (108/126, 85.7%), followed by upper respiratory tract infection (18.3%), gastroenteritis (6.3%), conjunctivitis (4.8%), meningoencephalitis (2.4%), and cystitis (1.6%). Significant immunosuppression was present in 29.4%. In multivariable analysis, independent predictors of 30-day mortality included mean arterial pressure ≤ 65 mmHg, SOFA score ≥ 5, increasing Charlson Comorbidity Index, central venous catheter placement, platelet count <50,000/µL (borderline significance), procalcitonin ≥ 0.1 ng/mL, and significant immunosuppression. The final model had 84.9% accuracy, 72.5% sensitivity, and 90.7% specificity. A high percentage of ICU patients with PCR-confirmed adenovirus infection died within 30 days. Hemodynamic instability, organ failure severity, comorbidity burden, inflammatory response, thrombocytopenia, and immunosuppression are key determinants of poor outcome.

A library of N[6]-modified adenosine derivatives (compounds 7-36) was synthesized via a one-step reaction of 6-chloro- or 2-amino-6-chloro-(β-D-ribofuranosyl)-9H-purine with primary or secondary amines. The structures of selected compounds (14, 31, 34) were confirmed by single-crystal X-ray diffraction, revealing diverse crystal packing motifs and hydrogen-bonding networks. Biological evaluation demonstrated a broad range of cytotoxic activities across a panel of cancer and non-cancer cell lines, ranging from highly potent to non-toxic derivatives. Structure-activity relationship analysis revealed that the biological properties of the synthesized compounds were strongly influenced by the nature of the N[6] substituent, with distinct structural features governing anticancer and antiviral activities. Several compounds (21, 22, 28, 30, and 32) markedly reduced cancer cell viability, with compound 28 exhibiting the highest potency across multiple solid tumor models. Importantly, compound 28 induced apoptosis, suppressed proliferation, and rapidly decreased cell viability in both HCT116 and HCT116 p53-/- colorectal carcinoma cells, indicating p53-independent activity. In contrast, cladribine displayed pronounced p53 dependence, promoting apoptosis primarily in p53-proficient cells and inducing a senescence-like phenotype rather than rapid cell death. Antiviral screening identified compounds 22, 25, and 35 as promising inhibitors of human parainfluenza virus type 3 (HPIV-3), whereas compound 12 exhibited the highest activity and selectivity against human adenovirus type 5 (AdV5). Collectively, these findings identify N[6]-modified adenosines as a promising class of compounds for developing anticancer agents with p53-independent activity and reveal several derivatives as attractive scaffolds for further optimization toward antiviral agents targeting respiratory viruses.

Human adenoviruses (HAdVs) cause a broad spectrum of diseases, ranging from mild respiratory and gastrointestinal infections to severe, sometimes even fatal illness in immunocompromised individuals. Species D adenoviruses represent the largest group, possibly driven by strong evolutionary pressure, particularly within the highly variable early transcription unit 3 (E3), which encodes immunomodulatory proteins. Among these, E3/49K is unique to species D and utilizes a particularly intriguing immunomodulatory strategy. It is a heavily glycosylated transmembrane protein that undergoes proteolytic shedding to release the soluble ectodomain (sec49K), the only known secreted HAdV protein. Both the membrane-anchored and soluble forms target the leukocyte-specific receptor-like protein tyrosine phosphatase CD45, a key regulator of immune cell activation. E3/49K binds CD45 with high affinity via two domains, inducing dimerization and inhibiting its phosphatase activity, thereby suppressing activation of T, B, and NK cells. The species specificity and potent immunomodulatory function of E3/49K underscore its role in adenoviral adaptation and highlight its potential for therapeutic immunosuppression and cancer therapy.

Acute respiratory infections caused by influenza A/B (Flu A/Flu B), respiratory syncytial virus (RSV), and adenovirus (ADV) remain a major global health burden. The COVID-19 pandemic profoundly altered respiratory virus transmission through nonpharmaceutical interventions (NPIs). Samples from patients with respiratory tract infections at Hangzhou Hospital of Traditional Chinese Medicine from January 2020 to October 2024 were collected. ADV, Flu A, Flu B, and RSV were detected to evaluate the impact of NPIs on viral epidemiology. Statistical analyses were performed using SPSS software and GraphPad Prism. Multivariable binary logistic regression models, adjusting for age group and sex, were constructed to evaluate the independent effect of NPI relaxation (strict NPI period 2020-2022 vs. post-relaxation period 2023-2024) on virus positivity. Stratified analyses by age group and demographic comparability assessments between periods were also performed. Overall virus positivity declined from 27.4% (2020) to 14.5% (2021) during strict NPIs, then rebounded to 35.1% in 2023 after relaxation. Flu A resurged atypically in summer 2022 and dominated the 2023 winter peak, while Flu B increased annually and peaked in 2024. ADV regained its prepandemic summer seasonality by 2024, whereas RSV showed limited seasonal variation. Higher ADV positivity was observed in males, and higher Flu B positivity in females. By 2024, influenza burden shifted toward adults and geriatric populations, while children under five remained most vulnerable to RSV and ADV. However, after adjusting for demographic shifts-including a significant increase in adult patients (18-60 years: 22.1%-40.0%) and altered sex ratios between periods (both P < 0.001)-the post-relaxation period showed lower adjusted odds of positivity for all four pathogens (Flu A: aOR = 0.64, 95% CI: 0.61-0.67; Flu B: aOR = 0.67, 95% CI: 0.63-0.70; ADV: aOR = 0.72, 95% CI: 0.68-0.76; RSV: aOR = 0.62, 95% CI: 0.59-0.65; all P < 0.001), whereas no significant sex differences were observed after multivariable adjustment (all P > 0.05). Stratified analyses further revealed that the magnitude of period-related risk reduction increased with age for all pathogens. This study demonstrates that the postpandemic resurgence of respiratory viruses in Hangzhou, Zhejiang Province, was not a monolithic recrudescence following NPIs relaxation, but a multifaceted shifting epidemiology driven by three convergent forces: expanded school-based and community screening that broadened the tested denominator, demographic case-mix shifts toward higher-risk adult populations, and pathogen-specific alterations in seasonal and age-specific transmission patterns. The consistently lower adjusted odds of positivity during the post-relaxation period indicate that crude resurgence signals must be interpreted through the lens of surveillance structure. This study demonstrates that the postpandemic resurgence of respiratory viruses in Hangzhou (2020-2024) was not a uniform transmission rebound following NPI relaxation, but a shifting epidemiology shaped by surveillance structural changes, pathogen-specific resilience, and altered population immunity. Multivariable models showed lower adjusted odds after restriction easing, while age-stratified analyses revealed heterogeneous period effects superimposed on stable risk hierarchies. In this subtropical Chinese city, influenza reasserted prepandemic seasonality, whereas RSV and ADV exhibited delayed recovery. These insights advocate for adaptive, age-targeted public health strategies-prioritizing adult vaccination for influenza and sustained pediatric prevention for RSV and ADV-that account for both biological transmission dynamics and surveillance artifacts in the post-COVID-19 era.