Search Results (967)

Rodents and shrews are important reservoir hosts due to their close association with human activities and their role in carrying various zoonotic pathogens. Recently, meta-transcriptomic sequencing has become a powerful tool for surveilling and screening novel pathogens from wild animals. However, many of these studies focused only on the diversity and genetic evolution of viruses from wildlife, while ignoring non-viral pathogens such as bacterial and eukaryotic microorganisms. Here, we performed a comprehensive infectome analysis of 227 tissue samples collected from 42 rodents and 16 shrews across six cities of Guangdong Province, China. We identified 34 viral families, including 23 mammalian viruses. Phylogenetic analysis revealed a henipavirus from the kidneys of shrews closely related to the Langya virus with potential infection risks to humans. Additionally, two potential pathogenic bacteria and 12 eukaryotic pathogens from six genera were found, showing clearer organ tropism than viruses. Interestingly, a moderate positive abundance correlation between Usmuvirus newyorkense and Trichinella suggested a potential virus–parasite association. We used machine learning models to evaluate the zoonotic potential of the obtained viruses, which indicated that 15 of 23 viral species were high risk for human infection. These findings provide important insight into the substantial zoonotic threat posed by pathogens circulating in wild small mammals in southern China and highlight the necessity for persistent wildlife pathogen surveillance. Full article

Background: The impact of climate change on birds’ migration and ticks’ reservoir habits is contributing to the spread of Crimean–Congo hemorrhagic fever (CCHF), caused by CCHF virus (CCHFV), to new continents and countries. CCHF is endemic to the Eastern Mediterranean Region, including Iraq, and is witnessing a substantial surge in confirmed cases with considerable disparity and gaps in managing CCHF cases. The increasing CCHF spread across Asia, Africa, and Europe, including Spain and Turkey, highlights the danger of its expansion. Developing high-confidence diagnostic criteria, identifying risk factors, and accurate predictors of CCHF outcomes are critical to managing suspected and confirmed cases of CCHF and to reducing the current case fatality rate of CCHF, which is the goal of this study. Methods: We completed a retrospective evaluation of 61 confirmed cases of CCHF in Basrah (Iraq). The cases were screened according to the clinical presentation, and CCHF cases were identified by ELISA and validated by PCR. Data was analyzed using SPSS version 22. T-tests, chi-square/Fisher exact tests, and Pearson’s correlation were used, with significance set at p < 0.05 and high significance at p < 0.01. Results: We found that repeated exposure to animals during animal slaughtering was a significant risk factor. In addition, 5% of the patients with confirmed CCHF, mainly from rural areas, reported exposure to rats. Clinical presentations included fever, headache, gastrointestinal problems, eye and orbital symptoms, and hemorrhagic complications. Predictors of death included advanced age, decreased platelet counts, and neuropsychiatric symptoms such as delusions and confusion. Conclusions: Our findings identify clinical and laboratory features of CCHF cases in Iraq, which will help to implement the most effective interventions to manage CCHF cases and protect the public in all Iraqi governorates. In summary, this study highlights a recent and significant rise in CCHF cases in Basrah Governorate, Iraq. Notably, 5% of confirmed cases reported contact with rats. The paper also proposes diagnostic criteria and identifies key predictors of mortality to support improved clinical management of CCHF. These findings underscore the urgent need for strengthened public health interventions, including enhanced infection prevention and control measures, increased awareness, and improved surveillance systems. The findings have important implications for improving control procedures, guiding therapeutic development, informing vaccine strategies, and supporting evidence-based policy alongside future research efforts. Full article

Variegated squirrel bornavirus 1 (VSBV-1) is a recently identified zoonotic virus associated with fatal encephalitis in humans. A literature search in electronic databases such as PubMed, Web of Science, Scopus, and Google Scholar was performed using the following search terms: “VSBV-1”, “orthobornavirus”, “squirrel”, “zoonotic encephalitis”, and “mammalian bornavirus”, to identify peer-reviewed literature relevant to the veterinary and zoonotic aspects of VSBV-1. This narrative review summarizes the current knowledge on VSBV-1 with emphasis on veterinary aspects, including taxonomy, epidemiology, clinical presentation, diagnostics, hypothetical transmission routes, surveillance strategies, and proposed biosecurity measures. However, evidence regarding virus shedding, natural reservoirs, distribution, and transmission pathways is presently absent. VSBV-1 may persist undetected in infected squirrels due to the absence of clinical signs and limited surveillance efforts. Large-scale epidemiological studies have not yet been performed. Given the limited understanding of viral epidemiology and the severe course of zoonotic infection, a precautionary approach is warranted. Structured surveillance, control of animal movements, and occupational protection are essential to limit both viral spread and the risk of zoonotic infection. Future research should focus on identifying natural reservoirs, virus distribution in captive squirrel populations, transmission pathways, and improving diagnostic tools. Full article

Culex pipiens is a widespread mosquito species with high ecological plasticity that thrives in urban, peri-urban and rural aquatic habitats. It is a major vector of West Nile virus (WNV), contributing to virus transmission among bird reservoirs and serving as a bridge vectorfor transmission to humans and mammals, which can result in neuroinvasive disease and fatalities. Controlling its populations reduces biting nuisance and associated economic and health burdens, making vector management essential for effective public health protection. Available methods to control this species are limited and require significant improvement because conventional strategies are often short-term, non-specific and ecologically problematic. The present study evaluated the efficacy of cyromazine granules on the Biodac carrier in laboratory, semi-field (in barrels) and field experiments (in canals). Content of cyromazine was 0.5 or 2%. Two formulations were tested: granules coated with stearate and uncoated granules. The highest efficacy was demonstrated by application of 2% cyromazine, both coated and uncoated, compared to the cyromazine with 0.5% active substance. Cyromazine showed high efficacy in the control of Cx. pipiens ranging from 85.8% to 100% in the laboratory, 68.1% to 100% in the semi-field and 48.1% to 98.8% in the field conditions (depending on the formulation applied), enabling long-lasting suppression of juvenile stages. In the laboratory, 53 days post-treatment, the residues were still present in the water. In the field experiment (in canals) the population reduction was recorded up to the 56th day post-treatment. Full article

Since 2022, numerous H5N1 highly pathogenic avian influenza virus (HPAIV) detections have been reported in wild and domestic mammals in North America. Although H5N1 HPAIV detections in dogs are rare, hunting dogs that retrieve waterfowl are at increased exposure risk due to their physical contact with reservoirs (waterfowl) and contaminated environments. A cross-sectional survey of hunters was conducted during 2024 to characterize hunting procedures, disease prevention practices, and interactions between humans and their hunting dogs to identify potential risks for zoonotic disease transmission. Descriptive analysis (N = 112) indicated a majority of participants considered their hunting dog as part of the family (93.8%), and less than half considered their dog a pet (42.9%). Of the 112 individuals, 96.4% did not utilize personal protective equipment (PPE) when handling a sick dog and 81.3% did not use PPE when handling harvested birds. This research demonstrated complex, sustained physical and personal connections between individuals and their hunting dogs. Additional research utilizing a One Health approach is necessary to define H5N1 HPAIV risk factors in hunting dogs and the environment’s role in the transmission of viruses among wildlife and domestic animals. Understanding zoonotic disease transmission in these populations can inform approaches to mitigate viral exposure. Full article

Background/Objectives: The emergence of SARS-CoV-2 variants and breakthrough infections underscores the need for next-generation vaccines capable of protecting from natural infection and/or preventing virus transmission. Intranasal vaccination offers a promising approach by eliciting local immune responses in the nasal mucosa, the primary site of infection and reservoir for transmissible virus. We evaluated two live-attenuated, respiratory syncytial virus-vectored vaccines in which the RSV F and G surface glycoproteins were replaced with a chimeric SARS-CoV-2 Spike protein from the ancestral USA/WA-1/2020 strain (MV-014-212) or the Delta variant (MV-014-212-delta). Methods: K18-hACE2 mice and LVG Syrian hamsters were vaccinated with a single intranasal dose of MV-014-212 or MV-014-212-delta. Systemic and mucosal immunity were assessed following vaccination, and protection was evaluated following Delta SARS-CoV-2 challenge. In vaccinated hamsters, morbidity, viral shedding, and lung inflammation and injury were also assessed following natural exposure to infected cagemates. Results: A single intranasal dose of either vaccine elicited systemic and mucosal immunity in K18-hACE2 mice, including serum neutralizing antibodies, Spike-specific memory B cells and plasmablasts, and Spike-specific CD8⁺ lung-resident memory T cells. Although MV-014-212-delta vaccination provided the best protection against the Delta variant virus challenge, both vaccines decreased viral loads in nasal discharge, lung, and brain, and reduced weight loss and mortality. In naturally acquired infection studies, vaccinated hamsters exposed to infected cagemates exhibited minimal weight loss, limited viral replication within the nasal mucosa, and attenuated lung pathology. Conclusions: Intranasal RSV-vectored vaccines can elicit broad protective respiratory immunity, suggesting that this platform could be leveraged for other respiratory pathogens. Full article

Bats are recognized reservoirs for a vast array of viral diversity, including members of the Hepadnaviridae family. Within a One Health framework, genomic surveillance of these animals is fundamental to understanding viral diversity and the potential risks of zoonotic spillover in high-density human population areas. This study describes the detection of a bat hepadnavirus through agnostic viral metagenomics in samples from passive surveillance collected in urban and peri-urban areas in Brazil. Sequencing was performed using the Oxford Nanopore Technologies (MinION) platform, and the bioinformatics pipeline involved de novo assembly and taxonomic identification against viral databases. We identified several contigs with similarity to the Tent-making bat hepatitis B virus (TBHBV) in a single liver sample. The largest contig (3182 bp) represents the complete genome, exhibiting a nucleotide identity of 80.93% with the original reference isolate. Our findings document the circulation of this viral lineage in a new epidemiological setting (the Brazilian urban interface), underscoring the importance of continuous surveillance to monitor the evolution and geographic distribution of bat orthohepadnaviruses and their relevance to public health. Full article

Background: Long-acting drug delivery strategies could augment pediatric human immunodeficiency virus (HIV) treatment effectiveness by bypassing population-specific challenges such as adherence. We harnessed pharmacokinetic (PK) modeling to develop a biodegradable, subcutaneous (SQ), reservoir-style implant for HIV treatment in 2–5-year-old children. Methods: Plasma was collected from New Zealand White rabbits over 30 h after a single intravenous (IV) bolus of bictegravir (BIC, 0.75 mg/kg), islatravir (ISL, 5 mg/kg) and/or emtricitabine (FTC, 30 mg/kg) then over a year after subcutaneous insertion of two to three implants eluting these antiretrovirals. Plasma antiretrovirals were quantified by HPLC-MS/MS and population PK models were fit to the IV PK profile to derive a mean unit impulse response (UIR). UIR was used to numerically deconvolve SQ absorption rate from the implant PK profile. SQ dosing rates were translated to pediatric plasma concentrations using published clinical PK parameters. Results: BIC, FTC, and ISL PK profiles were best described by two-compartment models. Each implant achieved quantifiable plasma concentrations for >360 days. Median SQ absorption rates (μg/day) at 3, 6 and 12 months of implantation were 116, 98 and 71 for BIC; 116, 37 and 5 for ISL; and 236, 116 and 24 for FTC. These 6-month dosing rates translated to pediatric plasma concentrations of 24 ng/mL BIC, 0.14 ng/mL ISL, and 0.7 ng/mL FTC. Conclusions: Our novel long-acting delivery platform exhibited antiretroviral SQ dosing rates for ≥6 months that are anticipated to achieve plasma concentrations in children within an efficacious range warranting further development for pediatric HIV treatment. Full article

Nipah virus (NiV) is a highly pathogenic zoonotic paramyxovirus responsible for sporadic outbreaks of severe disease with high case fatality rates in South and Southeast Asia. Human infection occurs through spillover from natural reservoirs, primarily fruit bats, or via human-to-human transmission, and is characterized by a broad clinical spectrum ranging from asymptomatic infection to acute respiratory disease and fatal encephalitis. Following entry via ephrin-B2 and ephrin-B3 receptors, NiV exhibits marked endothelial and neuronal tropism, leading to systemic vasculitis, disruption of the blood–brain barrier, and direct infection of the central nervous system. Disease progression is driven by a complex interplay between viral replication strategies and host immune responses. NiV effectively counteracts innate immunity through multiple viral proteins that inhibit interferon signaling, while simultaneously inducing dysregulated inflammatory responses that contribute to tissue damage and multi-organ failure. Neurological involvement represents the most severe manifestation, often resulting in acute or relapsing encephalitis with long-term sequelae among survivors. Despite the severity of the disease, no licensed antiviral therapies or human vaccines are currently available. Therapeutic development has focused on neutralizing monoclonal antibodies targeting viral glycoproteins and small-molecule antivirals that inhibit viral RNA synthesis, both of which show promising results in preclinical models, but remain limited by timing and translational challenges. In parallel, several vaccine platforms—including viral vectors, mRNA-based constructs, and recombinant protein subunits—have advanced to early-phase clinical trials, demonstrating encouraging immunogenicity. Beyond biomedical interventions, effective outbreak containment relies on integrated public health strategies. The “Kerala model” highlights the importance of rapid case identification, isolation, contact tracing, and community engagement within a One Health framework to mitigate transmission and reduce mortality. This review synthesizes the current knowledge on NiV pathogenesis, immune evasion, clinical manifestations, and emerging therapeutic and vaccine strategies, while highlighting critical gaps and future directions for improving the preparedness and response to this high-consequence emerging pathogen. Full article

Weed control of solanaceous weeds growing with solanaceous crops is a constant challenge. Infected by viruses, they can also act as virus reservoirs, complicating this problem further. Viromes of annual Solanum nigrum, Datura stramonium, and Solanum dulcamara, a perennial climbing shrub, were investigated using RNA sequencing and validated using RT-PCR, revealing infection with nine viruses. Broad bean wilt virus 1 (BBWV1), cucumber mosaic virus (CMV), and potato virus M (PVM) were found to infect S. nigrum. Investigating only 46 plants revealed infection with Solanum dulcamara yellow fleck virus (SDYFV) not only in S. dulcamara but in a new host, D. stramonium, which also represents a new host of turnip yellows virus (TuYV). We described the first presence of a potato virus H (PVH)-like, and Oxybasis rubra mitovirus 1 (OxruMV1)-like virus in Europe, in S. dulcamara as a new host. Our results highlight the unexpected complexity of the viromes of solanaceous weeds, which should be considered during reliable and efficient plant protection strategies, in order to alleviate the virus reservoir role of the weeds. Full article

Hepatitis E virus (HEV) is a zoonotic pathogen of global concern that circulates in both domestic and wild swine populations. Understanding its presence and dynamics in wildlife reservoirs is crucial for assessing spillover risks and designing One Health surveillance strategies. This study investigated the occurrence, genetic diversity, and evolutionary relationships of HEV in wild boars from mainland Portugal. A total of 120 animals from seven districts were tested, with HEV RNA detected in four cases (3.3%), all from the Évora district near the Spanish border. One positive sample was successfully sequenced, and phylogenetic analysis based on the complete genome classified it within the HEV-3m subtype, clustering with predominantly human-derived sequences from Spain and France, which highlights its zoonotic potential. A second phylogenetic analysis based on a partial genomic fragment, including sequences from domestic pigs in Portugal, revealed the co-circulation of subtypes 3e, 3f, and 3m without clear spatial or temporal patterns. Phylogeographic analysis suggested that the identified strain was most likely introduced from Spain, supporting the hypothesis of cross-border transmission through wild boar movement. No recombination events were detected in the sequence obtained in this study. These findings provide the first molecular evidence of HEV-3m circulation in wild boars in Portugal, offering valuable insight into the HEV strain circulation in European wildlife populations. The zoonotic potential of HEV and the likelihood of interspecies transmission highlight the need for coordinated cross-border surveillance and integrated One Health strategies. Full article

Bornaviruses are neurotropic, negative-sense RNA viruses with zoonotic potential, notably Borna disease virus 1 (BoDV-1) and variegated squirrel bornavirus 1 (VSBV-1). BoDV-1 is endemic in certain regions of Central Europe and maintained in bicolored white-toothed shrews, but its presence in Croatia has not been investigated. Given Croatia’s diverse biogeography and the prevalence of rodent-borne diseases, this study aimed to investigate the presence of orthobornaviruses in wild canids and mustelids. Brain samples from red foxes (Vulpes vulpes), golden jackals (Canis aureus moreoticus), wolves (Canis lupus), martens (Martes martes) and badgers (Meles meles) were analysed using pan-bornavirus RT-PCR. Despite successful RNA extraction and internal control amplification, bornavirus RNA was not detected in any of the 860 animal samples tested. Although no orthobornavirus RNA was detected, the results still provide valuable information: bornavirus infections appear to be absent or extremely rare in Croatian wild canids and mustelids. By excluding these species as current potential reservoir hosts, this study helps to refine the geographical extent of bornavirus endemicity and emphasises the importance of continuous One Health surveillance in regions with favourable ecological conditions for zoonotic spillover. Full article

Background: People living with HIV (PLWH) have a substantially increased risk of both AIDS-defining cancers (ADCs) and non-AIDS-defining cancers (NADCs), which remain a major cause of morbidity despite effective antiretroviral therapy (ART); this review aims to integrate current epidemiological, molecular, and clinical evidence on HIV-associated oncogenesis. Methods: A structured literature search was conducted in PubMed (2000–2026) using predefined keywords, including “HIV”, “cancer”, “oncogenesis”, and “immune dysregulation”, with inclusion of original studies, systematic reviews, and meta-analyses meeting predefined quality criteria. Results: Available evidence indicates that HIV contributes to cancer development through both direct and indirect mechanisms: viral proteins such as Tat, Nef, and Vpr disrupt apoptosis, DNA repair, and cell cycle regulation, while chronic immune activation, persistent inflammation, and immunosuppression impair tumor immune surveillance and facilitate oncogenic viral co-infections, including Epstein–Barr virus, human papillomavirus, and human herpesvirus 8. Emerging pathways, such as epigenetic alterations, microRNA dysregulation, metabolic reprogramming, and the contribution of HIV reservoirs to pro-tumorigenic microenvironments, further modulate cancer risk. Conclusions: HIV may function as a cofactor that enhances the effects of oncogenic viruses by promoting viral persistence and immune dysregulation; while biologically plausible, direct evidence linking HIV to amplification of tumorigenesis in humans remains limited. Full article

Background: Hepatitis E virus (HEV) is an increasingly recognized cause of acute viral hepatitis in Thailand as the burden of hepatitis A, B, and C has declined. HEV is a positive-sense RNA virus in the family Hepeviridae with three major open reading frames encoding replication proteins (ORF1), the capsid protein (ORF2), and an accessory protein involved in viral egress (ORF3). Unlike highly endemic regions where genotypes 1 and 2 are linked to waterborne outbreaks, infections in Thailand are reported mainly as sporadic cases associated with zoonotic transmission, most commonly genotype 3. Objectives: This review summarizes the epidemiology, transmission routes, and public health implications of HEV infection in Thailand. Methods: Peer-reviewed studies on HEV seroprevalence, molecular epidemiology, and transmission in Thailand were identified through PubMed using combinations of the keywords “HEV” and “Thailand”. Two investigators independently screened titles, abstracts, and full texts. Eligible studies were synthesized qualitatively. Results: Earlier studies suggested low population exposure, but more recent evidence indicates substantial cumulative risk. A nationwide survey among blood donors reported anti-HEV IgG seroprevalence of about 30%, with geographic variation and increasing prevalence with age. Detection of HEV RNA in pigs, slaughterhouse environments, and retail pork products, together with links to raw or undercooked pork consumption, supports pigs as the principal reservoir and foodborne exposure as an important route. Transfusion-associated infection has also been documented. Conclusions: In Thailand, HEV infection is linked mainly to zoonotic and foodborne transmission involving genotype 3. Stronger surveillance, food safety measures, and risk-based blood safety policies are needed. Full article

The rapid expansion of the golden jackal (Canis aureus) across Eastern Europe has reshaped mesocarnivore communities, with potential influence on the dynamics of zoonotic disease. In Romania, where both Trichinella spp. and rabies remain public health concerns, updated data on wildlife reservoirs are essential. This study aims to provide an integrated assessment of Trichinella prevalence and rabies virus-neutralising antibody (RVNA) profiles in 134 wild canids (96 golden jackals and 38 red foxes, Vulpes vulpes) from northwestern Romania (August 2025–January 2026). Trichinella larvae were detected using the artificial digestion method, and infection intensity was expressed as larvae per gram. Rabies serology was performed using a commercial ELISA kit, with 0.5 IU/mL considered the protective threshold. Trichinella prevalence was significantly higher in foxes (78.9%) in comparison with jackals (60.4%), with similar larval burdens in both species. More than half of the individuals in both species exhibited RVNA titers below the protective threshold, indicating heterogeneous immunity levels in the population. No significant age- or sex-related differences in seroconversion were observed. These findings confirm intense sylvatic circulation of Trichinella spp. and highlight potential immunity gaps in wildlife rabies control. The results support the need for integrated, multi-pathogen surveillance and explicit inclusion of the golden jackal in disease monitoring and management strategies. Full article