Search Results (3,420)

CRISPR-based diagnostics now detect viral, bacterial, and cancer-associated nucleic acids with sensitivities approaching quantitative PCR; however, their translation to decentralized care rests on computational design and interpretation that current datasets cannot sustain. Pandemic-era Cas12a assays reached 95% positive predictive agreement against reverse transcription quantitative PCR (RT-qPCR) at 10 copies/μL, and deep neural networks now design Cas13 detection assays spanning 1933 vertebrate-infecting viruses, ranking candidate guides at Spearman correlations of 0.69 to 0.84 across internal and external validation. Generative deep-learning systems improve single-nucleotide discrimination two- to three-fold, computer vision classifies lateral flow outputs at 96.5% accuracy, and multi-biomarker fusion reaches an area under the receiver operating characteristic curve (AUC) of 0.998 in lung cancer detection. These results mask a narrow data foundation. Cas13a guide prediction still draws from a single screening library of 19,209 guide–target pairs, Cas12a has one published diagnostic model, and signal classifiers almost uniformly validate on single-site cohorts. This review synthesizes mechanistic constraints, predictive and generative models, and point-of-care classifiers, and maps the path beyond this data ceiling. Evolutionary pretraining on RNA corpora and lab-in-the-loop agents that convert model failure into targeted data acquisition define the route forward. Full article

In Cambodia, livestock production plays an important role in the national economy and food security, yet tick-borne diseases remain an underrecognized constraint on animal health and productivity. Domestic animals may also serve as reservoirs of zoonotic pathogens in this predominantly rural setting. To address the lack of baseline molecular data on tick-borne pathogens in Cambodia, we conducted a cross-sectional study of ticks collected from November 2022 to April 2023 across 24 provinces. Ticks were collected from various hosts and environments, including cats, cattle, dogs, goats, pangolins, pythons, wild pigs, and bat cave floors, representing urban, rural, farm, wildlife rescue center, and forest fringe habitats. A total of 1526 ticks belonging to nine species were pooled into 352 samples and screened using conventional PCR (cPCR) targeting Anaplasma, Ehrlichia, Babesia, and Coxiella. Additionally, a subset of Rhipicephalus microplus ticks was analyzed using metatranscriptomic next-generation sequencing (NGS). Rhipicephalus microplus ticks collected from cattle tested positive for Anaplasma marginale (1.1% of pools) and Ehrlichia minasensis (0.9% of pools), whereas Rhipicephalus linnaei ticks collected from dogs were positive for Anaplasma platys (0.3% of pools) and Babesia canis (2.0% of pools). A high prevalence of Coxiella-like endosymbionts (15.6% of pools) was found in R. microplus from both cattle and goats. Metatranscriptomic analysis also identified six tick-associated viruses in R. microplus from cattle; with Guangdong tick manly virus being the most dominant (32.5% of samples); followed by Zhangzhou Totiv tick virus 1 (15.0%), Jingmen tick virus (5.0%), and Mogiana tick virus; Rhipicephalus-associated rhabdo-like virus; and Rhipicephalus-associated flavi-like virus; each at 2.5%. These findings provide the first molecular evidence of numerous bacterial, protozoal, and viral pathogens circulating in R. microplus and R. linnaei in Cambodia. The study highlights the need for integrated One Health surveillance to better understand, prevent, and control tick-borne diseases in the region. Full article

Phlebotomine sand flies are dipterans that transmit leishmaniasis, bartonellosis, and arboviruses of public health importance. Colombia is a tropical country with high annual incidences of arboviruses, such as dengue and, more recently, yellow fever, all of which have similar symptoms. This study characterized the viruses circulating in phlebotomine sand flies in two departments in the Colombian Caribbean. Between August 2023 and December 2024, a descriptive study was conducted in the Departments of Córdoba and Cesar in Colombia. Four municipalities were selected per department, and four insect captures were performed using CDC light traps. Specimens were taxonomically identified and organized into groups according to species and study area, and total RNA was extracted for NGS analysis. Short sequences were quality-assessed, assembled using MEGAHIT to obtain contigs, and classified using DIAMOND-MEGAN6 to select viral genomic sequences for phylogenetic analysis. Thirteen viral families were identified, including a virus from the family Rhabdoviridae in Pi. evansi in the department of Cesar and another from the family Dicistroviridae in Lutzomyia gomezi in both departments. Two genome segments of the family Phenuiviridae were found in Lutzomyia gomezi in the department of Córdoba, Colombia. Sand flies harbor a diverse range of viral families, some of which are previously undescribed, and can be studied to determine their taxonomy and assess their potential to infect vertebrate cells or their interactions with medically important pathogens such as Leishmania spp. Full article

Hantaviruses (HTVs) are lethal zoonotic pathogens responsible for hemorrhagic fever with renal syndrome and HTV cardiopulmonary syndrome; however, no specific antiviral treatments or vaccines have been approved. Bee products, such as propolis, honey, royal jelly, bee venom, and bee pollen, demonstrate extensive antiviral, anti-inflammatory, antioxidant, and immunomodulatory properties against various RNA and DNA viruses. No published research has directly evaluated bee products in relation to HTV infection. This review proposes a hypothesis-driven mechanistic framework suggesting that bioactive compounds from bee products may concurrently inhibit HTV replication, alleviate the cytokine storm, diminish oxidative stress, and maintain endothelial barrier integrity. We explicitly recognize the lack of direct experimental evidence regarding bee products’ efficacy against HTVs. Considering the mechanistic similarities with other enveloped viral infections and the recognized functions of NF-κB, Nrf2, and endothelial signaling pathways in HTV pathogenesis, we present a scientifically substantiated rationale for forthcoming research endeavors. The diverse bioactive compounds present in bee products including bee pollen, bee venom, honey, propolis, and royal jelly could provide a multifaceted strategy for inhibiting HTV pathology. We propose systematic in vitro, in silico, and in vivo investigations to assess the potential of bee-derived flavonoids, peptides, and fatty acids as adjunctive therapeutic strategies for HTV disease. Full article

Positive-strand RNA viruses represented by SARS-CoV-2 and DENV spread globally with high infectivity and frequent mutations, posing a severe threat to human health. However, specific and effective antiviral drugs remain limited. RNA-dependent RNA polymerase (RdRp) plays a critical role in the genome replication of RNA viruses and shows high structural conservation. No homologous protein exists in human cells, making RdRp an effective, safe, and broad-spectrum antiviral target. Therefore, establishing an RdRp activity assay for drug development based on its mechanism is of great significance. This paper summarizes the structural characteristics of RdRp and the methods for constructing RdRp activity assay, especially for cell-free activity assay. In addition, several reported RdRp inhibitors and their pharmaceutical progress are also reviewed, aiming to provide a reference for the development of novel antiviral drugs targeting RdRp. Full article

High-throughput sequencing is becoming the method of choice for plant diagnostics. It allows the detection of known and novel viruses and viroids, even in co-infection, without preliminary knowledge of the target. However, this method has its own limitations when compared to real-time PCR or ELISA. Laboratories that implement this type of technologies in-house must ensure that the performance criteria meet the requirements associated with their diagnostic activity. In this study, we present a workflow for in-house plant viruses and viroid detection, based on total RNA extraction, ribodepletion, Illumina sequencing and bioinformatics analyses. Performance criteria such as analytical sensitivity, analytical specificity, selectivity, repeatability, reproducibility and robustness were evaluated on the tomato brown rugose fruit virus (RNA genome), the tomato leaf curl New Delhi virus (DNA genome), and the pepper chat fruit viroid (RNA genome). The performance levels obtained meet the requirements for virus and viroid detection in symptomatic plant samples. Full article

DNA viruses rely extensively on host cellular machinery, including replication factors and transcriptional systems, to persist after infection. These mechanisms make studying and targeting DNA viral proteins challenging, as they also play key roles in mammalian processes. Traditional strategies include CRISPR-mediated gene disruption and small interfering RNA (siRNA) to target host proteins. However, Proteolysis Targeting Chimeras (PROTACs) offer a novel strategy by enabling the selective and rapid degradation of specific viral or host proteins involved in the DNA viral lifecycle. PROTACs are heterobifunctional molecules composed of three key components: a ligand that binds the target protein, a chemical linker, and a ligand that recruits an E3 ubiquitin ligase. By simultaneously binding both the target protein and the E3 ligase, PROTACs form a ternary complex. This proximity enables the E3 ligase to ubiquitinate the target protein, marking it for recognition and subsequent degradation by the intracellular proteasome. This approach represents a promising avenue for targeting previously undruggable proteins and improving therapeutic outcomes in virus-associated malignancies. In this perspective, we describe studies that use PROTACs as tools to modulate host proteins to investigate DNA viral processes with temporal control of host protein expression, as well as the use of PROTACs as antivirals to directly target DNA viral proteins. We also provide a detailed chart summarizing known host-targeting PROTACs and their potential applications across different stages of DNA viral lifecycles, highlighting opportunities for future DNA virus research. Full article

The yerba mate psyllid, Gyropsylla spegazziniana, represents a major pest affecting yerba mate production, leading to considerable economic losses. Although several aspects of its ecology and management have been investigated, little is known about the viruses associated with this insect pest. In this study, we conducted the first RNA high-throughput sequencing (HTS) analysis of G. spegazziniana to examine its virome, uncovering a diverse array of previously undescribed RNA viruses. Our analysis led to the identification of five novel viruses spanning different viral lineages. These include representatives with evolutionary affinities to beny-like, picorna-like, and sobemo-like viruses, provisionally designated as Gyropsylla spegazziniana beny-like virus 1 (GSBlV1), Gyropsylla spegazziniana picorna-like virus 1 (GSPlV1), and Gyropsylla spegazziniana sobemo-like virus 1-3 (GSSlV1-3), respectively. Phylogenetic analysis of the bi-segmented, highly divergent sobemo-like viruses revealed that these viruses are grouped with other insect-associated sobemo-like viruses. The beny-like virus clustered together with other insect-associated beny-like viruses, whereas the picorna-like virus clustered together with psyllid-associated picorna-like viruses. Overall, these findings demonstrate that G. spegazziniana harbors a complex and previously uncharacterized virome. This work provides a foundation for further research into the ecological significance, evolutionary patterns, and possible use of these viruses in biological control strategies of this major pest within yerba mate agroecosystems. Full article

Bemisia tabaci (whitefly; Hemiptera: Aleyrodidae), a complex of morphologically similar but genetically distinct species, causes enormous agricultural damage worldwide. Farmers incur billions of dollars in losses each year from whiteflies, both through direct feeding damage and from the transmission of numerous plant viruses. Important crops that are heavily damaged by whiteflies include tomato, eggplant, cucumber, cotton, cucurbits, beans, and cassava. The global invasiveness and persistence of B. tabaci are largely attributed to its exceptional biological traits. Understanding these traits is essential for developing effective, long-term pest management strategies. This review describes in detail how the basic biology studies of B. tabaci provide a foundation for developing pest management strategies. Specifically, we discuss: (1) insights into the development of insecticide resistance can guide resistance management strategies; (2) knowledge of natural enemies supports the advancement of biological control approaches; and (3) understanding plant–insect interactions reveals molecular targets for innovative pest management solutions. We also examine emerging research trends and offer future perspectives on how ongoing studies may drive the development of next-generation control strategies (RNA interference, clustered regularly interspaced short palindromic repeats—CRISPR-associated protein 9 (CRISPR-Cas9), and horizontally transferred genes as targets). Full article

Under a One Health framework, viruses of veterinary and zoonotic importance pose significant threats to animal and human health, food security, and livelihoods, particularly in regions with intense human–animal interactions. In West Africa, despite recent advances in surveillance programs, important gaps remain in understanding viral diversity and cross-species transmission at wildlife–livestock interfaces. We conducted metagenomic surveillance to characterize viruses circulating across livestock, domestic animals, and wildlife in rural Ghana in 165 animals sampled across five regions. Viral RNA from serum and tissue samples was sequenced with the Illumina platform, and genomes were de novo assembled with MEGAHIT. Phylogenetic relationships were reconstructed using Bayesian approaches. We report the first genomic sequences of porcine parvovirus 3, canine parvovirus, rotavirus A genotype R16, and bovine hepacivirus subtype B from Ghana in over a decade. Phylogenetic analyses revealed intercontinental linkages between Africa and Europe for parvoviruses, persistence of hepacivirus lineages, and evidence of cross-species transmission for rotavirus. Notably, detection in apparently healthy animals highlights underrecognized circulation, gaps in vaccination effectiveness, trade-related biosecurity vulnerabilities, and the role of wildlife in viral maintenance and transmission. Our findings reveal dynamic viral diversity and connectivity across animal populations and ecological interfaces, emphasizing the fluid and interconnected nature of pathogen circulation within One Health systems. By integrating metagenomics and phylogenetics, this study provides a scalable framework for enhancing surveillance capacity, enabling the early detection of emerging threats and informing targeted strategies to mitigate zoonotic and economically important viral diseases in West Africa. Full article

The hepatitis B (HBV), C (HCV), and D (HDV) viruses remain a major public health burden. Occult HBV infection (OBI) represents a hidden reservoir with clinical and epidemiological significance, yet its prevalence in Northwest Russia is unknown. We aimed to comprehensively assess the serological and molecular epidemiology of HBV, HCV, and HDV in St. Petersburg and the Leningrad region. Methods. In this cross-sectional study, 6773 apparently healthy volunteers were enrolled. Plasma samples were tested for hepatitis B surface antigen (HBsAg), antibodies to HBV core antigen (anti-HBc), antibodies to HBsAg (anti-HBs), antibodies to HCV (anti-HCV), and antibodies to HDV (anti-HDV) by ELISA. All anti-HCV- and anti-HDV-positive samples were tested for HCV RNA and HDV RNA by real-time PCR. All samples were tested for HBV DNA using a highly sensitive in-house nested real-time PCR assay (detection limit: 5 IU/mL). All “HBV DNA-positive, HBsAg-negative” cases confirmed by two independent extractions were classified as OBI. Vaccination status, self-reported history, and iatrogenic interventions were recorded. Results. Overall seroprevalence values were: HBsAg 1.7%; anti-HBc 11.3%; anti-HBs 43.0%; anti-HCV 1.9%; and anti-HDV 0.6%. Anti-HBc increased sharply with age (3.1% in children to 26.4% in the elderly, p < 0.0001), while anti-HBs declined (69.9% to 29.8%, p < 0.0001). HBV DNA was detected in 118 participants (1.7%). Of these, only 73 individuals (1.1%) were HBsAg-positive, while the remaining 45 participants (0.7%) had undetectable HBsAg, meeting the criteria for OBI. OBI was detected across all age groups, including children. Serological profiling of OBI cases revealed that 57.8% lacked both anti-HBc and anti-HBs, 35.6% had isolated anti-HBs, 2.2% had isolated anti-HBc, and 4.4% had both antibodies. HCV RNA was detected in 15.0% of anti-HCV-positive individuals (all adults). No HDV RNA was detected. Self-reported history underestimated true infection rates: 1.4% of those denying HBV infection were HBsAg-positive and 10.6% were anti-HBc-positive. Among those denying HCV infection, 1.4% were anti-HCV-positive. Vaccination coverage was 70.8%, declining from 90.9% in children to 39.0% in the elderly (p < 0.0001). Among vaccinated individuals, 48.0% lacked protective anti-HBs (<10.0 mIU/mL). Conclusions. This comprehensive serological and molecular study in Northwest Russia is the first to combine population-level serology with molecular detection of HBV, HCV, and HDV, including OBI in this region, and reveals that OBI accounts for a substantial proportion (38%) of all active HBV infections and is strongly associated with a history of iatrogenic interventions. The presence of OBI across all age groups, including children, shows that HBsAg screening alone substantially underestimates the true HBV burden. High rates of unrecognized infection and waning vaccine-induced immunity, highlight critical gaps in current surveillance. These findings provide an evidence-based rationale for integrating molecular testing into screening algorithms and for considering booster vaccination strategies to achieve viral hepatitis elimination goals. Full article

Background/Objectives: Respiratory syncytial virus (RSV), human metapneumovirus (hMPV), and parainfluenza virus type 3 (PIV3) are leading causes of acute respiratory infections in children and the elderly, yet no licensed T-cell vaccines are available. This study aimed to develop multivalent T-cell vaccine candidates against these pathogens using a live attenuated influenza virus (LAIV) vector platform. Methods: Conserved F, N, and M proteins of RSV, hMPV, and PIV3 were identified through multiple sequence alignments. Fragments enriched with experimentally confirmed and predicted T-cell epitopes were selected using the IEDB and NetMHCpan servers. These fragments were assembled into polyepitope immunogenic cassettes, and their selected order was determined by thermodynamic analysis of mRNA secondary structures using the RNAfold Web Server. The selected cassettes were cloned into the neuraminidase (NA) gene of a cold-adapted LAIV vector. Recombinant viruses were rescued by reverse genetics and assessed for replicative fitness in embryonated chicken eggs and MDCK cells, NA enzymatic activity and genetic stability upon serial passaging. Results: Four cassettes were designed for RSV, three for hMPV, and one for PIV3, all containing fragments with multiple T-cell epitopes. Three recombinant viruses of LAIV/RSV type and three of LAIV/hMPV type were successfully rescued, while attempts to recover the remaining recombinant viruses, i.e., LAIV/RSV and LAIV/PIV3, were not successful. All rescued recombinant viruses replicated to titers comparable to the parental LAIV strain and retained the full-length insert for at least eight passages in eggs. Importantly, NA enzymatic activity of the LAIV vector was not compromised by the insertion of the polyepitope T-cell cassettes. Conclusions: We developed a panel of recombinant T cell-based vaccine candidates against RSV and hMPV using the LAIV vector platform. These recombinant viruses encode conserved T-cell epitopes of the target viruses while retaining the biological properties of LAIV strains. Taken together, these characteristics warrant further evaluation of these recombinant viruses in appropriate relevant in vitro models to directly assess their immunogenicity in terms of stimulating a T-cell response against target pathogens. Full article

Oncolytic viruses (OVs) exploit key hallmarks of cancer to selectively replicate in malignant cells, leading to tumor cell lysis, modulation of the tumor microenvironment, and induction of antitumor immunity. These viral platforms have been engineered to enhance tumor specificity, intratumoral spread, and immunotherapeutic efficacy. Among them, rhabdoviruses, particularly vesiculoviruses, have emerged as promising candidates due to their rapid replication, high titers, and amenability to genetic manipulation. Maraba virus, a recently identified vesiculovirus, is a single-stranded negative-sense RNA virus with a favorable safety profile and minimal pre-existing immunity in humans. It demonstrates selective tumor tropism partly through low-density lipoprotein receptor (LDLR)-mediated entry and impaired antiviral responses in cancer cells. Genetic engineering of the wild-type Maraba virus led to the development of the MG1 strain, characterized by enhanced tumor selectivity, increased replication capacity, and potent cytolytic activity. Preclinical studies have demonstrated its efficacy as a monotherapy, a cancer vaccine vector expressing tumor-associated antigens, and in combination with chemotherapy and immune checkpoint inhibitors. MG1 also reshapes the tumor microenvironment, converting immunologically “cold” tumors into “hot” tumors, thereby enhancing immune-mediated tumor clearance. Compared to vesicular stomatitis virus, Maraba virus exhibits improved safety and reduced neurovirulence while maintaining strong oncolytic potential. This review aims to comprehensively summarize the biological characteristics of the MG1 Maraba virus, its genetic development, mechanisms of action, and current preclinical and clinical applications as a novel oncolytic immunotherapeutic agent. Full article

Segmented and non-segmented negative-strand RNA viruses share the same general pathway for genome transcription, which generates messenger RNA, and genome replication which duplicates the viral RNA. These processes are performed by the viral polymerase and necessitate the viral RNA to be coated by a non-covalent polymer of nucleoproteins known as nucleocapsid. The non-segmented negative-strand RNA viruses (nsNSVs) have rigid nucleocapsids covering the entire tightly bound genome and require a phosphoprotein cofactor for proper replication and transcription by the polymerase, while the segmented negative-strand RNA viruses (sNSVs) have very flexible nucleocapsids with only few nucleotides tightly bound to each nucleoprotein, and their viral RNA genome ends are directly bound to the polymerase. We discuss here how the differences in RNA binding are likely to be crucial for proper replication and transcription in both nsNSVs and sNSVs. Full article

Avian metapneumovirus (aMPV) is a major respiratory pathogen of poultry with a significant economic impact; however, its epidemiology at the wildlife–poultry interface remains poorly understood, particularly within Afro–Eurasian migratory systems. This cross-sectional study (December 2024–April 2026) investigated aMPV occurrence in wild birds across eleven Egyptian governorates representing key ecological zones along major migratory flyways. A total of 1280 samples were collected from 800 wild birds representing migratory waterfowl and synanthropic species, including 800 oropharyngeal swabs tested by real-time RT-qPCR for aMPV subtypes A and B and 480 serum samples analyzed using indirect ELISA. aMPV RNA was detected in 28/800 samples (3.5%), with all positives identified as subtype B and confined to the Nile Delta, Middle Egypt, and Canal Region. In contrast, serological analysis revealed a high seroprevalence of 58.3% (280/480), indicating widespread prior exposure with significant spatial and species-level variation (p < 0.05). The marked disparity between low molecular detection and high seroprevalence supports transient infection with cumulative exposure. The exclusive detection of subtype B may reflect epidemiological connectivity between poultry and wild bird populations within shared ecological interfaces; however, the directionality of transmission and the possibility of independent wildlife maintenance could not be determined within the scope of the present cross-sectional study. Future studies incorporating whole-genome sequencing, longitudinal surveillance, and broader flyway-scale sampling are needed to resolve transmission pathways and distinguish field strains from potential vaccine-derived viruses within wildlife–poultry interfaces. Full article