Search PubMedSearch

SEARCH · Search PubMed

Results for “host-virus associations”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

1,400 records · Page 2Linked to original sources

Systematic review of the mutations in the active antigenic site Ø of the prefusion F protein of the Respiratory Syncytial Virus (RSV) following the implementation of monoclonal antibody prophylaxis.

BACKGROUND: Monoclonal antibody (mAb) nirsevimab, which targets the antigenic site &#xd8; of the prefusion F protein (pre-F) of RSV, was introduced for RSV prophylaxis in several countries. METHODS: A systematic search was conducted between January 1, 2022, and July 31, 2026 for studies analyzing substitutions within the epitope of pre-F RSV protein, which is the target of nirsevimab, after the implementation of the mAb. We searched across PubMed, Scopus, Web of Science and ClinicalTrial.gov for studies involving children with confirmed RSV infection, that conducted genomic analysis. RESULTS: Seven studies (five observational and two randomized controlled trials) including 2156 RSV-positive samples (RSV-A: 1347, RSV-B: 809) were analyzed. RSV-A strains showed limited variability within antigenic site &#xd8;, with K65R being the most common substitution and K209E being the only intermediate-resistance RSV-A substitution. RSV-B strains demonstrated substantially higher substitution frequencies, particularly involving I206M, Q209R, and S211N. Most identified substitutions appeared to represent naturally occurring polymorphisms and retained susceptibility to nirsevimab, while multiple RSV-B substitutions and combinations involving residues 64-68 and 204-208 demonstrated reduced susceptibility or high-level resistance. Resistance-associated variants were detected in 28 of 2156 (1.3%) RSV-positive samples and exclusively among nirsevimab breakthrough infections. In a sub-analysis restricted to nirsevimab-treated individuals, resistance-associated variants were significantly more frequent among RSV-B than RSV-A (9.8% vs 0.5%; p&#xa0;<&#xa0;0.001). CONCLUSION: Most substitutions that were detected within the nirsevimab antigenic site reflect ongoing natural RSV evolution and do not significantly affect nirsevimab susceptibility. However, detection of resistance-associated variants highlights the importance of continuous genomic and phenotypic surveillance.

Humans

Clinical outcomes of Epstein-Barr virus infection/reactivation following CAR-T cell therapy: A systematic review.

BACKGROUND: Epstein-Barr virus (EBV) infection or reactivation is an emerging but underrecognized complication following chimeric antigen receptor T-cell (CAR-T) therapy and is likely associated with treatment-induced immune dysregulation. Data regarding its clinical impact remain limited. OBJECTIVE: To evaluate the reported occurrence, clinical manifestations, and outcomes of EBV infection or reactivation in adults undergoing CAR-T therapy. METHODS: A systematic review was conducted in accordance with the PRISMA 2020 guidelines. PubMed, Embase, and Cochrane CENTRAL were searched from inception to March 2025 for studies reporting EBV infection or reactivation after CAR-T therapy in adults. Due to limited and heterogeneous data, results were synthesized descriptively. RESULTS: Five studies comprising 80 patients were included (median age, 55&#xa0;years; 52.6% male among patients with reported sex data [10/19]). Across the included studies, 11 EBV infection/reactivation events were identified among 80 described CAR-T recipients, representing 13.8% of the reported sample rather than a true incidence estimate. Among events with usable individualized timing data, the median interval from CAR-T infusion to EBV detection/reactivation was 9.8&#xa0;months (approximate range, 1-44&#xa0;months). Because EBV surveillance strategies and definitions were inconsistently reported across studies, this proportion should not be interpreted as a true incidence estimate. Four patients (36.4%) developed EBV-associated disease, including three cases of EBV-related lymphoproliferative disorder and one case of EBV-associated diffuse large B-cell lymphoma. Among seven patients with reported post-CAR-T treatment response, four achieved Complete Remission/ Continuous Complete Remission; treatment response should be interpreted separately from final survival status. Confirmed EBV-related mortality occurred in 2/11 patients with reported EBV infection/reactivation and in 2/4 patients with EBV-associated disease; all-cause mortality could not be reliably estimated because patient-level vital status could not be fully attributed to the EBV-reactivated subgroup. Reported toxicities predominantly consisted of low-grade cytokine-release syndrome; however, toxicity data were limited. CONCLUSION: Although infrequently reported, EBV infection or reactivation after CAR-T therapy may be associated with substantial morbidity and mortality among affected patients. However, the available evidence is limited by the small sample size, heterogeneous study designs, and inconsistent EBV surveillance practices.

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

Maternal vaccination with RSVpreF and risk of hypertensive disorders of pregnancy: a systematic review and meta-analysis.

BACKGROUND: A bivalent respiratory syncytial virus (RSV) prefusion F protein-based vaccine (RSVpreF) was approved in the United States in August 2023 for use during pregnancy to prevent infant RSV-associated lower respiratory tract disease. The pivotal phase 3 trial identified a numerical imbalance in hypertensive disorders of pregnancy (HDP) that did not reach statistical significance; postmarketing observational studies have since reported inconsistent findings. We conducted a systematic review and meta-analysis to assess this association. METHODS: We searched MEDLINE, Embase, CENTRAL, Scopus, ClinicalTrials.gov, and WHO ICTRP from inception to Jan 26, 2026, for randomized controlled trials (RCTs) and observational studies comparing HDP outcomes in RSVpreF-vaccinated versus unvaccinated or placebo-receiving pregnant individuals. Unadjusted risk ratios (RRs) were pooled using a random-effects model; adjusted estimates from observational studies were pooled separately by inverse variance methods. This study is registered with PROSPERO (CRD420251026835). RESULTS: Nine studies were included (3 RCTs, 6 retrospective cohort studies; n&#xa0;=&#xa0;148,267). RSVpreF vaccination was associated with a small but statistically significant increase in overall HDP risk (RR 1&#xb7;08, 95% CI 1&#xb7;02-1&#xb7;13; p&#xa0;=&#xa0;0&#xb7;004; I2&#xa0;=&#xa0;44%), driven by the observational studies group (1&#xb7;08, 1&#xb7;02-1&#xb7;14; I2&#xa0;=&#xa0;61%); RCTs showed a directionally consistent but non-significant RR (1&#xb7;12, 0&#xb7;87-1&#xb7;43; I2&#xa0;=&#xa0;0%). The association was attributable to gestational hypertension, with no significant association for preeclampsia/eclampsia. CONCLUSION: Maternal RSVpreF vaccination was associated with a small increase in HDP attributable to gestational hypertension and driven primarily by observational studies, in which residual confounding remains possible. The benefits of infant RSV prevention remain substantial, and these findings support continued postmarketing surveillance and informed shared decision-making.

Humans

Liver Cancer Risk and Incidence Attributable to Human Immunodeficiency Virus: A Meta-Analysis and Population-Attributable Modeling Study of Over 1.2 Million Individuals.

HIV-induced immune suppression and chronic inflammation elevate the risk of cancer progression. We conducted a systematic review and meta-analysis of studies published between January 1, 1984 and October 13, 2023 to assess the association between HIV infection and liver cancer. People living with HIV (PLHIV) had a higher risk (pooled relative risk&#x2009;=&#x2009;3.36, 95% CI: 2.72-4.15). The global PAF for HIV-attributed liver cancer was 1.43% in 2019, with a three-fold increase over the past 30&#x2009;years. The Asia-Pacific region recorded the second highest new cases of HIV-attributed liver cancer in 2019, and the highest age-standardized incidence rate (ASIR) in Eastern and Southern Africa. Particularly, the ASIR of HIV-attributed liver cancer increased rapidly in Eastern Europe and Central Asia, with the highest estimated annual percentage change reaching 22.98%. PLHIV have an increased risk and incidence of liver cancer. In regions with high burden of HIV-attributed liver cancer, it is essential to integrate prevention and effective treatment for HIV, viral hepatitis, alcoholic liver disease, nonalcoholic steatohepatitis, and liver cancer.

Humans

Identification of a novel plant polerovirus in the whitefly Aleuroclava gordoniae.

We report the genome sequence of Aleuroclava gordoniae-associated polerovirus (AgAP), identified from the whitefly Aleuroclava gordoniae. The 5,650-nt AgAP genome contains 6 open reading frames. Phylogenetic analysis places AgAP within the genus Polerovirus, which comprises plant-infecting viruses. This study provides a genomic resource for further investigation of virus-insect associations.

plant virus

Whole genome sequencing of unusual Hepatitis C virus subtypes and drug resistance analysis during direct-acting antiviral therapy in India.

INTRODUCTION AND OBJECTIVES: Pangenotypic direct-acting antivirals (DAA) are effective against highly prevalent Hepatitis C virus (HCV) subtypes, but have been clinically validated almost exclusively in high-income countries. Unusual HCV subtypes may carry natural polymorphisms, potentially impacting DAA susceptibility. We conducted full-genome characterization and resistance analysis of unusual HCV subtypes in patients receiving DAA treatment. PATIENTS AND METHODS: In this prospective hospital-based study, eligible patients were screened for anti-HCV antibodies and active infection was confirmed by diagnostic 5'NCR-based HCV RNA detection. Genotyping was performed by core region sequencing, and viral load quantified by real-time PCR. For whole genome sequencing, multiplex primers were designed using alignments of global reference sequences. Sequencing was carried out using the Oxford Nanopore Technology platform. Phylogenetic analysis used multiple sequence alignment and the HCV-GLUE resource for resistance-associated substitution (RAS) analysis. RESULTS: Predominant genotype was genotype 3 in 64.3% (n = 45); genotype 6 in 21.4% (n = 15); and genotype 1 in 14.2% (n = 10). Unusual HCV subtype 6xa was detected in two patients and showed no NS5A resistance mutations. One genotype 3b patient relapsed at 24 weeks post-DAA treatment completion and carried NS5A resistance-associated substitutions 30 K and 31 M both at baseline and at relapse, conferring high-level resistance to NS5A inhibitors. CONCLUSION: This is the first report from India of whole genome sequencing of HCV subtype 6xa. The identification of NS5A resistance mutations in the 3b relapse case underscores challenges for global HCV elimination strategies.

Humans

Influenza A virus in Swiss pig herds with respiratory disease: Seasonality and age dependence.

Influenza A virus (IAV) is an important respiratory pathogen in pigs and poses a zoonotic risk to humans in close contact. While IAV epidemiology has been extensively studied in large-scale production systems, data from Switzerland - characterized by small herds and limited live pig imports - remain scarce. This exploratory nationwide cross-sectional study aimed to assess the association between herd-level IAV detection and reported respiratory disease in pig herds, and to explore associations with husbandry-, animal-, and human health-related factors. Between November 2023 and April 2025, 25 Swiss pig herds with caretaker-suspected respiratory symptoms were investigated. In each herd, five nasal swabs were collected and analyzed by quantitative PCR. Herd managers completed an interview, and clinical examinations were performed. Overall, 56&#x2009;% (95&#x2009;% CI: 37,1 - 73,3) of herds tested positive for IAV, comparable to reports from other European countries. The estimated intra-herd detection rate was 49,6&#x2009;% (95&#x2009;% CI: 31,2 - 68,0). Respiratory disease outbreaks associated with IAV detection showed indications of seasonal variation, with no positive herds identified during summer. Across age groups, pigs aged 11-14 weeks had a higher likelihood of IAV detection, with 15,79-fold increased odds (95&#x2009;% CI: 1,50 - 860,4), although with considerable uncertainty. The interpretation is limited by the small sample size, heterogeneous data, and reliance on single time-point qPCR detection. The results suggest that IAV detection in clinically apparent respiratory outbreaks may follow seasonal patterns in Swiss pig herds. Weaners and newly introduced fattening pigs may play a role in such respiratory outbreaks and could represent relevant targets for IAV surveillance in Switzerland. Continued monitoring and the implemen tation of appropriate control measures remain important given the virus's zoonotic potential and impact on pig health.

Animals

MARK1 suppresses infectious bursal disease virus replication via phosphorylating VP3.

Infectious bursal disease virus (IBDV) of the Birnaviridae family is a non-envelope, double-stranded RNA virus that encodes a VP3 protein with multiple functions, which controls viral genome replication, IFN-&#x3b2; production, and virus traffic in infected cells. Posttranslational modifications (PTMs), such as ubiquitination, of VP3 have been demonstrated for affecting its function and stability. To clarify the mechanism by which VP3 is regulated in IBDV infected cells, we focused on the phosphorylation of VP3. Mass spectrometry analysis identified that microtubule-affinity regulating kinases 1 (MARK1) was a kinase interacting protein of VP3. Inhibitory function of MARK1 in affecting viral replication was validated. We describe the phosphorylation event at the serine 130 (S130) and serine 163 (S163) residues of VP3 mediated by MARK1 via mass spectrometry analysis. Alanine replacement of the phosphorylation sites in VP3 significantly enhanced its RNA-binding activity. Additionally, the mutation of two serine residues led to remarkably improved in its polymerase-enhancing function. We then incorporated the two mutations to rescue recombinant IBDV. Viral growth curve analysis revealed that replication of mutant IBDV was significantly enhanced relative to wild type (WT) virus. In conclusion, we found that VP3 functions are specifically regulated by MARK1 mediated phosphorylation at S130 and S163 and that this regulation suppresses IBDV replication ultimately.

Infectious bursal disease virus

Epidemiological status of bovine viral diarrhea virus in water buffalo (Bubalus bubalis): A global systematic review and meta-analysis.

Bovine viral diarrhea virus (BVDV) remains a neglected viral disease in water buffalo despite its significant economic impact in production systems. Although limited epidemiological studies have been reported worldwide, the serostatus and active infection in buffalo have not been systematically reviewed. A systematic review and meta-analysis were conducted to estimate BVDV prevalence in water buffalo and identify associated epidemiological factors. Relevant studies published up to January 31, 2026, were retrieved from five electronic databases. A total of 49 studies were identified from 15 different countries were found for inclusion. A random-effects model was used to estimate pooled-prevalence and assess heterogeneity among studies. A meta-analysis of 37 studies (9270 buffalo) estimated a pooled BVDV seroprevalence of 30.5%, while analysis of 16 studies (7189 animals) indicated an antigen prevalence of 16.5%. Continent-wise analysis revealed the highest BVDV seroprevalence in South-America (44.0%), while antigen prevalence was highest in Africa (21.2%) followed by Asia at 12.2%, and no BVDV data reported from North-America. Among the different countries, the highest BVDV seroprevalence was detected in Turkey (61.6%) and Argentina (59.0%), while antigen prevalence was highest in Egypt (21.2%), with lower estimates in Brazil (11.8%) and Iraq (11.3%). Notably, high heterogeneity (I2&#xa0;>&#xa0;90%) was observed in the all-pooled estimates, indicating variations in sampling period, age, sex, sample source and types, diagnostic methods, production-system, and study quality. These findings demonstrate the widespread presence of BVDV in water buffalo populations and indicate the need for targeted control strategies to mitigate its impact on health and productivity.

Animals

In Situ Hybridization and RT-PCR Detection of Nervous Necrosis Virus in Fourfinger Threadfin, Eleutheronema tetradactylum, in Taiwan.

Between April and July 2020, suspected outbreaks of nervous necrosis virus (NNV) infection were observed in fourfinger threadfin (Eleutheronema tetradactylum) fingerling hatcheries in Pingtung County, southern Taiwan. Affected fish exhibited spiral swimming behaviour and abdominal distension, resulting in mortality rates between 50% and 100%. Histopathological examination showed severe vacuolation in the brain and ocular tissues, with large oval and/or irregular basophilic cytoplasmic inclusion bodies in the brain. Phylogenetic analysis of the viral replicase (RNA1) and capsid protein (RNA2) genes revealed high nucleotide sequence identities among the isolates in this study, with sequence similarity rates of 96.9%-99% for RNA1 and 98.2%-99.0% for RNA2 compared to RGNNV reference strains available in the NCBI GenBank database. This is the first detection of betanodavirus in fourfinger threadfin in Taiwan, using RT-PCR and ISH. A positive correlation between elevated water temperatures and disease severity indicates the need for year-round surveillance and genomic analysis to clarify the epidemiology of FTNNV. The data suggest that infected eggs may facilitate the vertical transmission of Betanodavirus. Crucially, utilising virus-free broodstock, alongside routine health screening and environmental control, is essential for mitigating NNV risks in fourfinger threadfin aquaculture.

Animals

Oropouche virus: viral evolution, epidemiological trends, and challenges for control.

PURPOSE OF REVIEW: In recent years, OROV has emerged as a significant public health threat beyond the Amazon region. Here we review current epidemiological, virological, clinical and ecological knowledge of OROV to inform health practitioners, public health authorities and the scientific community and to facilitate the development of effective control strategies for OROV. RECENT FINDINGS: We describe the epidemiological, virological, ecological and clinical characteristics of OROV, focusing on lessons from the recent expansion, and highlighting needs for control and management of this emerging arbovirus. SUMMARY: This review aims to inform health practitioners, public health authorities and the scientific community of the recent reemergence and expansion of OROV beyond the Amazon Basin. The ecology, epidemiology, virology of OROV and clinical presentations of OROV infection are discussed, and knowledge gaps are identified.

Humans

Algae-to-host horizontal gene transfer in Paramecium bursaria is associated with host adaptation during endosymbiosis.

Paramecium bursaria maintains a stable endosymbiosis with green algae, yet the evolutionary consequences of this association remain unclear. Here, we screened the host genome for algal-derived horizontally transferred genes (HTGs) using a lineage-aware workflow designed to detect horizontal gene transfer (HGT) between two defined lineages. We identified 16 candidate HTGs, including four putative newly transferred genes and 12 homologous transferred genes, most of which were functionally associated with redox homeostasis and metabolism. Five HTGs showed symbiosis-dependent expression. RNAi knockdown of GH32s and SATs reduced host proliferation, total cell area, and motility, while GH32s knockdown also reduced endosymbiont load. Duplication patterns suggest that most transfers may have occurred after the P. bursaria lineage diverged from the sampled Paramecium species but before its lineage-specific whole-genome duplication (WGD). The HTGs also showed host-associated shifts in GC content and gene length, while representative HTGs retained conserved domains and functional motifs. Together, our results support algae-to-host HGT in P. bursaria and suggest that some transferred genes may contribute to metabolic integration during endosymbiosis.

Gene Transfer, Horizontal

Global molecular and serological evidence of dengue and chikungunya infection: a systematic review and meta-analysis of 158,608 tested participants.

INTRODUCTION: Dengue virus (DENV) and chikungunya virus (CHIKV) are Aedes-borne arboviruses with overlapping clinical manifestations, shared vectors, and substantial diagnostic challenges in co-endemic settings. This systematic review and meta-analysis synthesized published evidence on molecular detection, serological positivity, and DENV-CHIKV dual positivity/co-infection in human clinical, surveillance, and community-based study populations. CONTENT: Following PRISMA 2020 guidance, five bibliographic databases (PubMed/MEDLINE, Scopus, Web of Science, ScienceDirect, and Google Scholar) and supplementary grey-literature/preprint sources were searched for English-language studies published from 1 January 1980 to 31 December 2024. No prospective PROSPERO or OSF protocol registration was available. Eligible records reported extractable numerators and denominators for DENV and/or CHIKV in humans using recognized molecular or serological assays. A total of 196 studies comprising 158,608 tested or suspected participants were included in the extraction table. The pooled CHIKV estimate was 14.0&#x202f;% (95&#x202f;% CI: 12.0-16.4; I2=97.5&#x202f;%), with molecular and serological estimates of 9.8 and 15.7&#x202f;%, respectively. The pooled DENV estimate was 13.8&#x202f;% (95&#x202f;% CI: 10.9-17.3; I2=99.0&#x202f;%), with molecular and serological estimates of 13.1&#x202f;% (95&#x202f;% CI: 7.9-21.0) and 14.3&#x202f;% (95&#x202f;% CI: 10.2-19.8), respectively. DENV-CHIKV dual positivity/co-infection was 52.9&#x202f;% (95&#x202f;% CI: 48.7-57.1) among studies that tested and reported both outcomes. Country-level estimates varied widely and should be interpreted as summaries of available studies rather than nationally representative burden estimates. Funnel-plot asymmetry was statistically significant in DENV analyses but not in the overall CHIKV analysis. SUMMARY: Available evidence indicates extensive but highly heterogeneous DENV and CHIKV positivity across selected clinical and surveillance populations. The pooled estimates should be interpreted cautiously because of substantial between-study heterogeneity, diagnostic variability, outbreak-period sampling, and uneven geographic representation. OUTLOOK: The findings support integrated arboviral surveillance, multiplex diagnostics, and vector-control preparedness in co-endemic regions.

Humans

Identification and functional characterization of a novel antiviral chicken interferon-&#x3c5;.

Interferons are critical mediators of antiviral immunity in vertebrates. While type IV interferon (IFN-&#x3c5;) has been identified in fish and amphibians, its existence and function in chickens remained unknown. Through systematic genomic screening, we identified and cloned a novel chicken interferon gene, designated ChIFN-&#x3c5;. Phylogenetic analysis placed ChIFN-&#x3c5; within a distinct clade alongside zebrafish and clawed frog IFN-&#x3c5;, confirming its identity as a type IV interferon, with minimal homology to classical type I, II, or III IFNs. Expression profiling revealed constitutive ChIFN-&#x3c5; expression in mucosal and immune tissues of healthy chickens, exhibiting a distinct developmental shift: highest in trachea and small intestine in 1-day-old chicks, shifting to spleen and lung in 4-week-old chickens. ChIFN-&#x3c5; expression was strongly upregulated following H9N2 AIV infection. Functionally, recombinant ChIFN-&#x3c5; protein activated the interferon-stimulated response element (ISRE) and Mx promoter in a dose-dependent manner and significantly inhibited the replication of both vesicular stomatitis virus (VSV) and H9N2 AIV in DF-1 cells. In vivo, early treatment with exogenous ChIFN-&#x3c5; significantly reduced pulmonary and tracheal viral loads and decreased oropharyngeal and cloacal virus shedding in H9N2-infected chickens. In conclusion, this study identifies and functionally characterizes the type IV interferon in chickens, elucidating the evolutionary status, regulated expression, and antiviral efficacy of ChIFN-&#x3c5;. These findings highlight its potential as a candidate for developing interferon-based therapies against avian viral diseases.

Animals

ALG-020572, an Antisense Oligonucleotide for the Treatment of Chronic Hepatitis B Virus Infection Discontinued for Drug-Induced Liver Injury.

Current treatment options for chronic HBV infection are suboptimal in that they fail to suppress HBsAg levels. ALG-020572 is an antisense oligonucleotide designed to reduce viral protein synthesis through degradation of HBV mRNA. ALG-020572-401 was a double-blind, randomized, placebo-controlled trial consisting of two parts. Part 1 (single-ascending doses) evaluated the pharmacokinetics, safety and tolerability of single doses of ALG-020572 or placebo in healthy participants. In Part 2 (multiple dosing), participants with non-cirrhotic HBeAg-negative, virologically suppressed chronic HBV infection were administered up to 7 doses of ALG-020572 to evaluate safety, pharmacokinetics and antiviral activity. In Part 1, 32 participants were randomized to ALG 020572 or placebo. Single doses of ALG-020572 up to 480&#x2009;mg were well tolerated. The most common treatment-emergent adverse event reported was injection site reaction. ALG-020572 was rapidly absorbed and plasma exposures increased with dose. In Part 2, 8 participants with non-cirrhotic HBeAg-negative virologically suppressed chronic hepatitis B infection were enrolled and received up to 7 doses of ALG-020572. The study was prematurely discontinued after 4 participants experienced significant alanine aminotransferase elevations that were subsequently attributed to drug-induced liver injury. Single doses of ALG-020572 demonstrated a favourable pharmacokinetic and safety profile in healthy participants. Unexpectedly, ALG-020572 was poorly tolerated in participants with chronic HBV infection, resulting in the early termination of the study and further development of ALG-020572 due to idiosyncratic drug-induced liver injury, suggesting caution is required in the development of this class of drugs. Trial Registration: Registered at clinicaltrials.gov: NCT0500102.

Adult

Longitudinal whole-genome analysis of bluetongue virus identifies conserved serotype-specific genomes and distinct genomic constellations within a Colorado sheep flock (2021-2023).

Bluetongue virus (BTV) is a segmented double-stranded RNA virus of ruminants transmitted by Culicoides spp. biting midges. Although the genome consists of ten segments, classification into serotypes is primarily based on genome segment 2. However, reassortment among genomic segments is a major driver of BTV evolution and diversity. This study used longitudinal whole-genome sequencing to characterize BTV genomes collected from 2021 to 2023 within a single sheep flock in Colorado, where multiple serotypes co-circulate. Whole-genome sequences were generated from fourteen blood samples representing four serotypes: BTV-6, -11, -13, and -17. Longitudinal sampling identified multiple BTV serotypes within individual sheep across consecutive years. Tanglegram analysis comparing segment phylogenies to the segment 2 tree demonstrated incongruent topologies across all genomic segments, suggestive of reassortment or the circulation of distinct genomic constellations. Nucleotide-level comparisons revealed high sequence homology among same-serotype samples from the same year, while the greatest genetic divergence was observed among BTV-17 genomes collected in different years. Additionally, all BTV-13 genomes contained a previously undescribed nonsynonymous substitution in segment 10 predicted to extend the encoded protein by three amino acids. Together, these findings demonstrate that highly conserved BTV genomes and distinct genomic constellations can be detected at the flock level across multiple years. This longitudinal whole-genome approach reveals the genetic complexity of endemic BTV populations, including novel variants and genomic patterns consistent with reassortment that are lost with conventional serotyped-based approaches, highlighting the need to integrate whole-genome characterization into endemic BTV monitoring programs.

Animals

Triacylglycerol metabolism is a novel target to combat West Nile virus infection.

West Nile virus (WNV) is a zoonotic Orthoflavivirus transmitted by mosquitoes that is responsible for outbreaks of meningitis and encephalitis worldwide. Driven by climate change, WNV has expanded as a global public health concern, particularly in temperate regions. However, there are still no specific approved therapies, reinforcing the need for antiviral development. Previous works have documented that WNV multiplication strictly depends on certain cellular lipids. To identify novel lipid-related therapeutic targets, we analyzed the infection driven alterations in the CNS lipidome, the primary tissue supporting WNV replication. Our results indicated that the major alterations in the brain lipid content of WNV-infected mice corresponded to triacylglycerols (TAGs). Moreover, transcriptomic analysis showed that infected brains underwent changes in the expression of TAG metabolism. Supplementation with exogenous fatty acids increased lipid droplets (LD) content and promoted viral replication in cell culture models. On the contrary, pharmacological intervention in TAG metabolism using diacylglycerol acyltransferase inhibitors (DGATi) suppressed WNV multiplication in cell culture models. As a proof-of-concept of the therapeutic potential of DGATi, treatment of mice with A922500 reduced viral burden in the brain and proinflammatory cytokine production. Overall, our results unveil the importance of LDs and glycerolipid metabolism for WNV and highlight the potential of therapeutic interventions targeting this pathway to control viral replication and neuroinflammation.

West Nile virus; lipid