Search Results (618)

Background: Hepatitis C virus (HCV) remains a major cause of preventable liver-related mortality in the United States despite highly effective direct-acting antivirals (DAAs). Contemporary assessment of mortality trends and disparities is essential for elimination efforts. Methods: Using CDC WONDER multiple cause-of-death data (1999–2023), we identified HCV-related deaths using ICD-10 codes for acute and chronic HCV (B17.1, B18.2) and calculated age-adjusted mortality rates (AAMRs) per 100,000 (2000 US standard). Rates were stratified by sex, race/ethnicity, census region, and 2013 NCHS urban–rural classification. Joinpoint regression quantified temporal inflection points and annual percent changes (APCs). Results: Overall HCV-related AAMR increased from 1.8 (1999) to a peak of 5.0 (2014), then declined to 2.3 (2023), with a marked post-2014 decrease (APC −8.2%). Mortality was consistently higher in males than females (2023 rate ratio 2.57). In 2023, American Indian/Alaska Native individuals had the highest mortality (AAMR 8.7; rate ratio 3.48 vs. non-Hispanic White), followed by non-Hispanic Black individuals (AAMR 6.2; rate ratio 2.48). Mortality remained highest in the West and was higher in non-metropolitan than metropolitan counties (AAMR 2.8 vs. 2.3; rate ratio 1.22), with a slower post-2014 decline in non-metropolitan areas. Conclusions: Our findings indicate that while the DAA era has been associated with a substantial reduction in HCV-related mortality at the national level, this progress has not been uniform across all populations. Persistent excess mortality among Native American and non-Hispanic Black individuals may reflect inequities in the HCV care cascade, including screening, confirmatory testing, linkage to specialty care, insurance-related restrictions, and the high cost of antiviral therapy. These results highlight the need for policies and public health strategies that improve equitable and affordable access to curative HCV treatment. Full article

The innate immune system, particularly the retinoic acid-inducible gene I (RIG-I)-like receptor (RLR) signaling pathway, is a major early defense barrier against influenza A virus infection. However, excessive immune responses can trigger lethal cytokine storms and severe immune-mediated pathology. In this study, we performed a genome-wide CRISPR/dCas9 gene activation screen in human lung epithelial (A549) cells by using an A/Puerto Rico/8/1934 (H1N1) reporter virus, and identified the ubiquitin-specific protease USP17L13 as a novel negative regulator of innate immunity that promotes influenza virus replication. Overexpression of USP17L13 significantly enhanced the replication of multiple subtypes of influenza viruses in A549 cells, including a human pandemic H1N1 virus, seasonal H3N2 viruses, as well as a globally circulating clade, 2.3.4.4b, of the highly pathogenic avian H5N1 virus. Transcriptomic analysis demonstrated that USP17L13 suppresses host antiviral defenses by downregulating nuclear factor kappa B (NF-κB) signaling and arachidonic acid metabolism, while upregulating pathways associated with ribosomal translation and oxidative phosphorylation to facilitate viral production. Mechanistically, USP17L13 attenuates the host interferon (IFN) response by promoting the degradation of the key viral RNA sensors, RIG-I, and melanoma differentiation-associated protein 5 (MDA5). Further analysis revealed that USP17L13 is inducible by type I and type II interferons as well as inflammatory cytokines, suggesting that it may act as a negative-feedback regulator to limit excessive inflammation. Collectively, our findings identify USP17L13 as a previously unrecognized proviral host factor and provide new insight into how host deubiquitinases shape influenza virus-host interactions, with potential implications for host-directed approaches to controlling excessive inflammation during viral infection and improving influenza vaccine production. Full article

RNA viruses exhibit high mutation rates, necessitating antivirals targeting conserved infection mechanisms. In this study, viral hemorrhagic septicemia virus (VHSV), a non-human pathogenic negative-sense RNA virus, was used as a surrogate model to enable high-throughput antiviral screening under reduced biosafety conditions. A recombinant VHSV expressing enhanced green fluorescent protein was used to screen 17,265 compounds, 2000 plant extracts, and 100 marine extracts. Among the candidates, the leaf extract of Phellodendron amurense Rupr. (PL extract) exhibited antiviral activity with low cytotoxicity (selectivity index ≈ 10). The extract reduced viral infectivity in a dose-dependent manner and showed cross-activity against snakehead rhabdovirus. Mechanistic analyses indicated that the PL extract acts primarily at early stages of infection. Virucidal assays demonstrated direct, time-dependent inactivation of viral particles, while pre-treatment reduced host cell susceptibility. Time-of-addition experiments confirmed that antiviral activity was restricted to early infection, suggesting interference with viral attachment or entry rather than intracellular replication. Fractionation revealed that activity was associated with the non-polar n-hexane fraction, implicating lipophilic compounds that may disrupt viral envelope integrity or membrane interactions. These findings suggest that P. amurense leaf extract is a promising candidate for broad-spectrum antivirals targeting conserved entry processes in enveloped RNA viruses. Full article

Dengue virus (DENV) and SARS-CoV-2 are emerging viral pathogens that share overlapping clinical features, including fever, fatigue, and respiratory symptoms, complicating differential diagnosis in endemic regions. Their co-circulation has increased the risk of co-infections, which may result in unpredictable disease progression, increased morbidity, and mortality. This overlap presents a significant challenge in managing outbreaks, as both viruses pose a major public health threat. Vaccines and direct-acting antivirals may be rendered ineffective by viral mutations, making it difficult to address evolving strains. Host-directed antivirals offer a promising alternative, potentially maintaining efficacy against a multitude of variants. Both DENV and SARS-CoV-2 rely on host proteases for viral maturation and entry, with furin playing a crucial role in viral glycoprotein cleavage. In DENV, furin cleaves the prM protein, facilitating virion maturation, while in SARS-CoV-2, the polybasic furin cleavage site in the spike protein enhances viral entry. This makes furin a compelling pan-viral target, where inhibiting furin could reduce viral fitness without relying on viral mutations. This review highlights the therapeutic rationale for targeting furin and discusses luteolin, a furin inhibitor showing antiviral activity against both viruses. Furin-targeted therapies may offer a durable antiviral strategy effective across DENV serotypes, SARS-CoV-2 variants, and co-infection settings. Full article

Although ombitasvir/paritaprevir/ritonavir plus dasabuvir (OPrD) therapy is highly effective for chronic hepatitis C (CHC), clinicians frequently encounter transient hyperbilirubinemia, which can be misidentified as hepatotoxicity. This study investigated the role of SLCO1B1 (OATP1B1) and SLCO1B3 (OATP1B3) genetic polymorphisms in predicting bilirubin spikes and distinguishing transporter-mediated interference from hepatocellular injury. In this prospective study of 65 patients with HCV genotype 1, genotyping for OATP1B1 (c.388A>G, c.521T>C) and OATP1B3 (c.334T>G, c.699G>A) was performed using PCR-RFLP and capillary electrophoresis (QIAxcel Advanced System). Clinical and biochemical parameters were monitored over a 12-week treatment period. Hyperbilirubinemia (total bilirubin >1.1 mg/dL) developed in 18.5% of the cohort, typically within the first month. A distinct ‘AST-dominant’ biochemical signature, elevated bilirubin and AST paired with stable ALT, was identified, suggesting transporter-specific interference rather than hepatocyte damage. Statistical analysis pinpointed the OATP1B3 c.699G>A (rs7311358) variant as the sole genetic driver (p = 0.007). Carriers of the c.699G>A allele faced a 6.3-fold higher risk of developing hyperbilirubinemia (OR: 6.30, 95% CI: 1.48–26.80, p = 0.032), while no significant associations were found for OATP1B1 variants. We conclude that OATP1B3 c.699G>A is a potent predictor of OPrD-induced hyperbilirubinemia. Identifying this genotype pre-treatment allows clinicians to anticipate transient, benign bilirubin elevations and prevent unnecessary drug discontinuation, thereby mitigating therapeutic inertia and ensuring treatment continuity for CHC patients. Full article

Objectives: The World Health Organization (WHO) goal of eradicating hepatitis C virus (HCV) infection by 2030 has encouraged healthcare providers to implement proactive strategies to improve diagnosis and treatment. The aims of this retrospective cohort study were to assess a program designed to improve the HCV care cascade and facilitate access to treatment, within a national healthcare provider in Israel, Maccabi Healthcare Services (MHS). Methods: Included were adult patients newly diagnosed with HCV infection before and after the implementation of a screening and care optimization program. Patients diagnosed in 2017 served as the reference group (RG), while those diagnosed in 2019 (following the program implementation) comprised the intervention group (IG). Study outcomes included completion of HCV laboratory testing, time to consultation with gastroenterologist/hepatologist (GE), and initiation of treatment with direct-acting antivirals (DAAs). Results: The study sample included 356 HCV Ab+ patients in the RG (median age = 46 years; 41% females), and 328 in the IG (median age = 48 years; 39% females). Compared to RG, IG demonstrated higher rates of patient visiting GE visit (78.1% vs. 63%) and initiating DAA treatment (66.3% vs. 35.5%). Conclusions: Implementation of a restructured HCV care cascade was associated with a greater proportion of patients receiving expert consultation and higher DAA treatment uptake, important steps towards HCV eradication. Full article

Background: Hepatitis C viral infection (HCV) has historically been a leading indication for liver transplantation (LTx), primarily due to its progression to cirrhosis and hepatocellular carcinoma (HCC). However, the advent of direct-acting antiviral agents (DAAs) over a decade ago has revolutionized HCV treatment, achieving sustained virologic response (SVR) in over 90% of patients and potentially altering LTx indications. Aim: To investigate the impact of DAAs on HCV-related indications, with or without HCC, and model future trends in LTx indications. Methods: We retrospectively reviewed 1504 liver transplants performed between 2000 and 2024 at a single center. Patients were categorized into three cohorts: HCV-only, HCC-only, and HCC with HCV co-infection (HCC/HCV). Relative transplant volumes by-year, post-operative outcomes, and HCC recurrence rates were analyzed across pre- and post-DAA eras. ARIMA modeling was employed to project trends in transplant indications through the year 2030. Results: The proportion of transplants for HCV alone declined by 82.3% from 2015 to 2020, while HCC/HCV transplants decreased by 68.8%. Conversely, the total number of transplants for HCC alone increased during this period, with a modest proportional decrease of 8.3% from 2015 to 2020. ARIMA modeling suggests that by 2030, LTxs for HCV alone may be nearly eliminated. The projected proportion of transplants conducted for HCC alone remains the highest of all three study indications at 4.3%. Conclusions: DAAs have reduced LTx due to HCV. By 2030, LTx for HCV-related cirrhosis, particularly without HCC, may be obviated. This underscores the need to reevaluate allocation for emerging oncologic indications. Full article

Background: Direct-acting antivirals (DAAs) achieve high sustained virologic response (SVR) in hepatitis C virus (HCV) patients with cirrhosis, yet the risk of hepatic decompensation or hepatocellular carcinoma (HCC) persists. Fibrosis-4 (FIB-4), a pre-treatment index that predicts advanced fibrosis, is linked to HCC risk post SVR. We compared post-SVR outcomes and care engagement, and determined the optimal pre-treatment FIB-4 index to predict the risk of HCC or decompensation in HCV patients with cirrhosis treated at the Department of Corrections (DOC) and non-DOC clinics. Methods: HCV patients with cirrhosis treated with DAAs since 2014 in the HCV Treatment Registry were included. Cirrhosis was defined by elastography, imaging, or clinical criteria. Patients with prior decompensation or HCC were excluded. Outcomes (HCC, decompensation) were collected from records. The FIB-4 index was compared between DOC and non-DOC groups. Results: Among 2104 cirrhotic patients (mean age 54; 76% male), 53% were treated in DOC via telemedicine and 47% in non-DOC clinics. HCC developed in 4.8% and decompensation in 8.1%. DOC patients had lower FIB-4 scores and SVR, partly from higher loss to follow-up (9% vs. 1%). Of 1581 with follow-up, surveillance was more common in non-DOC, which also had higher HCC and decompensation. A higher baseline FIB-4 index independently predicted HCC and decompensation (cutoffs: 3.24, 3.7; AUROC 0.79, 0.75, respectively). Conclusions: Despite SVR, cirrhotic patients—especially with a high FIB-4 index—remain at risk for HCC and decompensation. Outcomes differ by care setting, highlighting the need for continued AASLD-recommended surveillance post-SVR. Full article

Hepatitis C virus (HCV) infection is a global health concern, chronically affecting over 71 million people. It primarily targets the liver but also causes systemic complications through inflammation, oxidative stress, and metabolic dysregulation. HCV is a highly variable RNA virus with six major genotypes that are mainly transmitted via blood. Often asymptomatic, the infection progresses silently to chronic hepatitis C (CHC), which can lead to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Direct-acting antivirals (DAAs) have revolutionized treatment, achieving cure rates above 95%, improving liver function, reversing fibrosis, and normalizing metabolism. HCV disrupts iron metabolism by suppressing hepcidin, causing iron overload and oxidative stress. It also alters lipid metabolism, inducing steatosis, and affects glucose metabolism, contributing to insulin resistance and type 2 diabetes. DAAs improve these metabolic outcomes. HCV promotes oxidative stress via viral proteins, damaging liver cells and DNA and triggering inflammation and fibrogenesis. Even post-cure, oxidative stress and iron overload may continue to drive disease progression. Genetic and epigenetic factors influence fibrosis progression and HCC risk. Despite a sustained virologic response (SVR), patients with advanced liver damage remain at risk for HCC and metabolic diseases, highlighting the need for continued monitoring and personalized post-treatment care. Full article

Respiratory syncytial virus (RSV) is a major pathogen responsible for severe lower respiratory tract infections in infants, the elderly, and immunocompromised individuals. Because the RSV F protein mediates viral entry and 15-lipoxygenase (15-LOX) amplifies virus-induced inflammatory responses, dual targeting of these proteins may provide both antiviral and anti-inflammatory benefits. In this study, we combined computational prediction with experimental validation to identify natural dual-target inhibitors from the Traditional Chinese Medicine Systems Pharmacology Database (TCMSP). A total of 13,131 natural compounds were screened by drug-likeness evaluation, molecular docking, ADME assessment, and molecular dynamics simulations, yielding 31 potential dual-target candidates with favorable drug-like properties. Among them, rhoeadine (MOL001473) maintained stable binding conformations with both targets throughout 100 ns simulations. In BEAS-2B cells, rhoeadine exhibited significant anti-RSV activity (EC50 = 1.82 µM), low cytotoxicity (IC50 = 34.50 µM), and a selectivity index (SI) of 18.97. Time-of-addition experiments suggested that rhoeadine primarily acts at the early stage of viral infection. Additionally, ELISA results indicated that rhoeadine significantly inhibited RSV-induced secretion of CCL5 and IL-6, highlighting its anti-inflammatory potential. In summary, this study identified rhoeadine as a promising natural compound with antiviral and anti-inflammatory activities against RSV. Computational analyses suggested its potential association with RSV F protein and 15-LOX, although direct target-level validation is still required. Full article

Background: The landscape of hepatitis C virus (HCV) infection has been changing with the introduction of direct-acting antivirals (DAAs). This study evaluates 15-year temporal trends of anti-HCV and HCV-RNA positivity in a regional referral center in Türkiye, analyzing the impact of DAA treatments, the COVID-19 pandemic, and the 2023 earthquakes on disease dynamics. Methods: Laboratory data of patients tested for anti-HCV antibodies and HCV-RNA between 2011 and 2025 were retrospectively analyzed after excluding repeat records. Positive patients were categorized by antibody titers (1–4.99 S/Co and ≥5 S/Co) and viremia status. Poisson, beta, and quantile regression models were determined annual trends in case numbers, positivity rates, and median ages. Results: A total of 402,557 patients underwent anti-HCV screening over 15 years. While annual test volume increased 2.25-fold, the number and rate of high-titer (≥5 S/Co) positive patients decreased four-fold, significantly. HCV-RNA positivity rates remained stable between 2011 and 2016 but declined sharply from 2017, falling approximately 19.2% annually (p < 0.001). Significant diagnostic disruptions occurred in 2020 (pandemic) and 2023 (earthquakes). An “aging trend” was identified; the median age of viremic patients increased by over 5.5 years throughout the study period. Conclusions: The introduction of DAAs in 2016 marked a milestone, leading to a nearly 90% reduction in the viremic patient burden in our region. The steady aging of the HCV-positive population suggests that the infected pool is shrinking and is not replenished. However, global and regional crises can hinder screening efforts, necessitating resilient public health strategies to achieve World Health Organization 2030 elimination targets. Full article

Background/Objectives: This retrospective study investigates the prevalence and distribution of HCV genotypes among 233 genotyped patients from the Epirus region of Northwestern Greece from 2014 to 2024. Methods: Genotypes were detected by molecular diagnostic assays, and their association with demographic parameters and viral load was analyzed. Results: The most prevalent subtype was 3a (50.2%), especially among younger and male patients, followed by subtypes 1b and 1a. A statistically significant association was found between genotype and both age and sex, while genotype distribution did not significantly differ by national origin. Furthermore, subtype 6c-I was found only in a non-native case, suggesting a possible introduction of this rare strain. Viral load showed no significant difference by sex, genotype, or age group. A notable decline in HCV cases was documented during the COVID-19 pandemic, underscoring the impact of the public health crisis on HCV diagnosis. Despite the decreasing need for genotyping in the direct-acting antiviral (DAA) era, our findings support the continued molecular surveillance of circulating HCV strains. Conclusions: This is the first study to longitudinally assess HCV genotype dynamics over a full decade (2014–2024) in the Epirus region of Northwestern Greece, capturing trends during the COVID-19 era and documenting the emergence of rare genotypes. It contributes to the evolving knowledge of HCV epidemiology in Southeastern Europe. Full article

The immunosuppressive nature of porcine reproductive and respiratory syndrome virus (PRRSV) remains the central obstacle to its effective control. Conventional microRNA (miRNA)-based antiviral approaches are limited by their modest potency and the high risk of viral escape. Here, we rationally designed an engineered miRNA carrying a 5′-triphosphate (5′-PPP) terminus that integrates RIG-I-driven innate immune activation and sequence-specific gene silencing within a single molecule. In vitro-transcribed 5′-PPP miRNAs are efficiently recognized by the pattern-recognition receptor RIG-I, triggering a robust type I interferon response that counteracts PRRSV-induced immunosuppression. In MARC-145 cells, one such construct, 5′-PPP BZL-sRNA-20, potently inhibited PRRSV replication through the synergistic action of immune activation and gene silencing. However, in porcine alveolar macrophages (PAMs)—the natural host cells for PRRSV—the antiviral effect depended primarily on 5′-PPP-induced interferon responses, with the targeting sequence providing limited or context-dependent benefits. Dual-luciferase assays confirmed that the gene-silencing activity depends on 5′-PPP modification, which enhances the stability of BZL-sRNA-20. This bifunctional strategy establishes an “immune activation plus targeting” paradigm by simultaneously acting as a RIG-I ligand that triggers broad antiviral responses and specifically cleaves viral RNA via direct base-pairing to conserved regions of the PRRSV genome. These findings reveal the potential of engineered 5′-PPP miRNAs as immunomodulatory antiviral agents, while highlighting that the contribution of RNAi targeting varies depending on the cellular context. Full article

Dengue virus (DENV) is a mosquito-borne RNA virus that causes serious illness in humans, ranging from mild fever to severe clinical manifestations, with dengue virus type 2 (DENV-2) being the most virulent among its four serotypes. Despite extensive research, no specific antiviral therapy is currently available, making the host-directed method an appealing therapeutic approach. Evidence shows that DENV manipulates host kinase-driven phosphorylation pathways to control viral pathogenesis. Using the kinase–substrate phosphomotif approach, we predicted phosphorylation sites across the DENV proteome and their potential human kinases. The predicted kinase–substrate interactions were systematically integrated with DENV-2-induced human phosphoproteome datasets, protein–protein interactions, and experimentally-validated viral phosphosites. The therapeutic relevance of the identified host kinases was corroborated by the impact of their inhibitors on DENV-2 infection. Among the 359 potential human kinases predicted to phosphorylate DENV-2 proteins, based on human phosphoproteome and kinase–viral protein interaction analyses, CDK9 emerged as a central hub kinase. Molecular docking analyses further revealed that the host kinases CDK9, EEF2K, HASPIN, and TNNI3K form stable interactions with the viral capsid and NS5 proteins. Additionally, a conservation analysis suggested that the predicted phosphorylation sites are evolutionarily conserved across DENV-2 strains. Computational prediction tools supported the predicted kinase–substrate interactions, underscoring the role of host kinases as key regulators of DENV infection, which may act as potential therapeutic targets. This study highlights the interplay between dengue viral and host proteins, providing insights into host-directed therapeutic strategies for DENV-2 infection and their potential to address the current lack of effective antiviral interventions. Full article

Porcine reproductive and respiratory syndrome virus (PRRSV) infection relies on glycolytic reprogramming to support replication, but the mechanisms driving this metabolic shift remain poorly understood. The stimulator of interferon genes (STING), an innate immune adaptor, recently emerged as a metabolic regulator by directly binding and inhibiting hexokinase-2 (HK₂), a key rate-limiting enzyme in glycolysis. Whether PRRSV exploits the STING-HK₂ axis to unleash glycolysis for its own replication is unknown. Here we demonstrate that PRRSV infection induced STING degradation and promoted HK₂ suppression, activating glycolysis for viral replication. In PRRSV-infected Marc-145 cells, lactate production (a glycolysis marker) and HK₂ expression increased time-dependently, peaking at 48 h post-infection (hpi). Conversely, STING protein levels decreased significantly at 36 hpi and further at 48 hpi, suggesting a correlation between STING downregulation and glycolytic activation. The HK₂ inhibitor 2-deoxy-D-glucose reduced lactate production and viral load, while the glycolysis activator PS48 enhanced both. STING knockdown via siRNA increased HK₂ expression, lactate secretion, and PRRSV nucleocapsid protein levels, whereas STING overexpression suppressed these phenotypes. Co-immunoprecipitation and confocal microscopy demonstrated direct STING-HK₂ interaction and cytoplasmic co-localization, maintained during PRRSV infection. HK₂ overexpression promoted viral replication without altering STING levels, confirming HK₂ as a downstream effector. In conclusion, PRRSV-triggered degradation of STING enhances HK₂ expression, promoting lactate accumulation and accelerating viral replication. These findings suggest that the STING-HK₂ axis can act as a critical viral metabolic checkpoint and highlight targeting metabolic–immune crosstalk as a potential anti-viral strategy. Full article