Search Results (322)

Background: Messenger RNA (mRNA) vaccines have emerged as a versatile platform beyond SARS-CoV-2, with expanding applications in infectious diseases and oncology. However, comprehensive evidence synthesis of non-SARS-CoV-2 mRNA vaccines remains limited. Methods: This systematic review followed PRISMA 2020 guidelines and was registered in PROSPERO (CRD420261323500). MEDLINE, Embase, Web of Science, Scopus, ClinicalTrials.gov, and WHO ICTRP were systematically searched for studies published between 1 January 2000 and 28 February 2026. Eligible studies included phase I–III clinical trials and in vivo preclinical studies evaluating non-SARS-CoV-2 mRNA vaccines. Two reviewers independently screened studies, extracted data, and assessed risk of bias using RoB 2, ROBINS-I, and SYRCLE tools. Findings were synthesized narratively because of substantial heterogeneity. Results: A total of 40 studies met the eligibility criteria and were included in the review, comprising 20 clinical studies and 20 preclinical studies. Advanced clinical programs targeted influenza and respiratory syncytial virus (RSV), with phase III trials displaying seroconversion rates above 70% with good safety profiles. Preliminary phase I studies for HIV, cytomegalovirus, rabies, and personalized cancer mRNA vaccines showed promising humoral and cellular immune responses. Preclinical studies showed strong antibody and T-cell responses against malaria, tuberculosis, Group B Streptococcus, and Zika virus. Most adverse events were mild to moderate, while serious vaccine-related adverse events were uncommon. Conclusions: Non-SARS-CoV-2 mRNA vaccines demonstrate substantial translational potential across infectious disease and oncology applications. Although the vaccine candidates have demonstrated promising immunogenicity and safety, most are in the early stages of development. This highlights the need for large trials, long-term safety follow-up and better global representation. Full article

Metabolic state strongly shapes social and reproductive behaviors, yet the neural circuits that convert internal energy signals into behavioral responses remain poorly defined. The ventral premammillary nucleus (PMv) of the hypothalamus has been implicated in this process, particularly through leptin receptor-expressing (LepRb) neurons, but its brain-wide circuit organization is still unclear. Here, we used Cre-dependent retrograde (RV) and anterograde (HSV) viral tracing techniques in LepRb-Cre mice to construct a comprehensive, single-cell-resolution input–output map of PMv^LepRb neurons. 3D reconstruction showed that these neurons receive dense convergent inputs, mainly from hypothalamic and forebrain regions involved in energy balance, motivation, and limbic processing. In contrast, their outputs extend not only back to several input regions but also prominently to midbrain and pontine autonomic centers, including the periaqueductal gray (PAG) and parabrachial nucleus (PB). Quantitative analysis revealed that forebrain regions were more likely to participate in reciprocal connectivity, whereas brainstem regions were dominated by outgoing projections. This organization suggests that PMv^LepRb neurons are positioned to integrate metabolic and motivational signals and relay them to downstream systems controlling instinctive behavioral and autonomic responses. These findings provide a structural basis for understanding how energy state can influence decisions related to social competition and reproduction. Full article

Lyssaviruses are neurotropic viruses that cause fatal encephalitis, with the rabies virus as the most prominent member. The viral glycoprotein (G) plays a key role in infection and is the main target of adaptive immune responses. This study aimed to comparatively analyze linear B- and CD4⁺ T-cell epitopes in the G protein ectodomain of lyssaviruses from phylogroups I (RABV, EBLV-1, EBLV-2, DUVV, and ABLV) and II (LBV and MOKV) using bioinformatics tools. Protein sequences were obtained from GenBank, processed to isolate ectodomains, aligned for identity analysis, and used to generate consensus sequences. CD4⁺ T-cell epitopes were predicted based on HLA-II binding affinity, while linear B-cell epitopes were identified using physicochemical properties and assessed for N-glycan masking. Amino acid identity ranged from 76.71% to 83.79% in phylogroup I and 82.72% in phylogroup II. Phylogroup I showed a higher density of HLA-II epitopes (0.22) than phylogroup II (0.18). Despite differences in antigenicity distribution, conserved linear B-cell epitopes in both phylogroups overlapped with peptides binding to HLA-II DRB1*15:01 and were not masked by N-glycans. These findings highlight putatively conserved antigenic regions identified through computational analysis and may support future studies focused on the development of improved vaccines and immunoprophylactic strategies against lyssaviruses. Full article

Efficient in vitro production of rabies virus is essential for vaccine development and quality control applications. High-density cultivation systems offer practical advantages for rabies virus production but also create culture conditions in which nutrient depletion, waste accumulation, and progressive deterioration of host-cell condition may limit infectious virus output. In this study, we evaluated the effects of sodium pyruvate supplementation on rabies virus CVS-11 production in Vero and BSR cells cultivated in a high-density macrocarrier-based tide-motion culture system under serum-containing and serum-free conditions, with complementary comparative observations in conventional monolayer cultures of BHK cells. Cultures were infected at a multiplicity of infection of 0.01, and infectious virus production was assessed over time, together with cell density, glucose consumption, and pH dynamics. Sodium pyruvate supplementation was associated with significantly higher infectious virus titers, delayed culture deterioration, prolonged maintenance of viable cell populations, and higher peak infectious titers in both Vero and BSR cultures. The highest infectious titers were observed under serum-free pyruvate-supplemented conditions, reaching 7.5 log₁₀ FFU/mL in Vero cells and 7.2 log₁₀ FFU/mL in BSR cells. Across the tested conditions, serum-free cultivation and pyruvate supplementation were both associated with significantly higher peak infectious titers. In contrast, exploratory correlation analysis based on condition-level summary values indicated an inverse association between minimum culture pH and peak infectious titer. Together, these findings show that sodium pyruvate supplementation can improve infectious rabies virus yield and prolong the productive phase in high-density macrocarrier-based cultures, supporting its use as a practical culture-modulation strategy for CVS-11 production in adherent cell systems. Full article

Rabies is a fatal zoonotic viral disease that continues to pose a significant threat to both animal and public health worldwide. Despite considerable progress in its control across Europe, sporadic outbreaks still occur, particularly in regions where wildlife reservoirs and stray animal populations sustain virus circulation. This study provides one of the first comparative longitudinal analyses integrating European countries and Turkiye rabies surveillance data over a decade (2013–2023). Information on reported outbreaks was obtained from the Animal Disease Information System (ADIS) and the World Animal Health Information System (WAHIS) database. The analysis focused on temporal trends, regional differences, and the distribution of affected animal species. During the study period, a total of 4865 outbreaks were reported in 16 countries. The number of detected outbreaks declined considerably over time, decreasing from 1022 cases in 2013 to 325 cases in 2023, representing an overall reduction of approximately 68%. The temporal trend was not uniform, with periods of decline followed by temporary increases. The highest number of outbreaks was registered in Türkiye, followed by Romania and Poland, indicating pronounced regional disparities. Domestic dogs represented the most frequently affected species, while cases were also recorded in wildlife and domestic cats, confirming the epidemiological importance of both domestic and wild reservoirs. The observed reduction in the number of outbreaks reflects the impact of vaccination programs and coordinated control measures, but may also be influenced by differences in surveillance systems and reporting practices. Nevertheless, the persistence of rabies in several regions indicates that the disease remains an epidemiological concern. Sustained vaccination of domestic animals, continued wildlife immunization, and strengthened surveillance and cross-border cooperation are essential for long-term control and prevention. Full article

Rabies is a fatal zoonotic disease once clinical symptoms develop. In Europe, sustained animal rabies control programs have led to a marked decline in animal rabies and subsequently human rabies cases; however, sporadic infections continue to occur. In July 2025, a fatal case of autochthonous (locally acquired) human rabies was confirmed in Romania following a stray dog bite in a patient who did not receive post-exposure prophylaxis (PEP). Here, we report the first molecular characterization of a human rabies virus (RABV) strain isolated in Romania and place it in the context of contemporaneously circulating animal-derived RABV strains. Rabies virus infection was confirmed intra vitam by fluorescent antibody testing and both conventional and real-time RT-PCR on cerebrospinal fluid and saliva, with postmortem confirmation on skin and brain tissue. Whole-genome sequencing was performed on the human isolate and on 22 animal-derived RABV strains collected in northern Romania in 2025. Phylogenetic analyses revealed that all recent Romanian sequences clustered within the North-East European (NEE) rabies virus phylogenetic group and segregated into two geographically distinct genetic clusters: a north-western cluster, closely related to strains from Slovakia and Poland, and a larger north-eastern cluster, linked to viruses circulating in eastern Romania and the Republic of Moldova. The human-derived RABV genome was grouped within the north-eastern cluster and showed the highest genetic similarity to animal viral strains from the same geographical area, supporting a local transmission event. This demonstrates the importance of integrating human viral genomic data into the national rabies surveillance framework. 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

Background: Rabies is a highly fatal zoonotic disease that causes approximately 59,000 human deaths worldwide each year. Current inactivated rabies vaccines require multiple doses and are associated with high costs. The full-length rabies virus glycoprotein (RVG), a membrane protein, exhibits substantial instability in its trimeric structure during recombinant expression. This instability makes it difficult to obtain high-purity, correctly folded antigens. Objectives: This study focuses on the preparation of a full-length recombinant RVG subunit vaccine candidate expressed in a glycoengineered Pichia pastoris system with mammalian-like glycosylation. Methods: The full-length RVG gene (including the transmembrane domain and cytoplasmic tail) from the Challenge Virus Standard-11 (CVS-11) strain was codon-optimized and inserted into the pPICZαA vector to construct the recombinant expression plasmid pPICZαA-RVG. The plasmid was transformed into glycoengineered Pichia pastoris X33-7 (low-mannose type) by electroporation for inducible expression. The target protein was purified by nickel affinity chromatography, anion-exchange chromatography, and Superdex-200 size-exclusion chromatography. The structural characteristics of the purified protein were analyzed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The purified antigen was formulated with the adjuvants AS03 or MF59. BALB/c mice (n = 5 per group) were immunized intramuscularly following a four-dose schedule (days 0, 7, 14, and 28). Antigen-specific IgG antibody titers were measured by ELISA, and neutralizing antibody titers were determined using the rapid fluorescent focus inhibition test (RFFIT). Results: Glycoengineered Pichia pastoris yeast strains expressing wild-type RVG (RVG-WT) or a mutant variant (RVG-M6: R84S, R199S, H270P, R279S, K300S, and R463S) were successfully constructed. The purified RVG antigen formed nanoparticles with an average particle size of approximately 75 nm. Immunized mice generated robust RVG-specific IgG responses, with titers reaching approximately 6.31 × 10⁵ for RVG-WT after the fourth immunization, compared to 3.16 × 10³ for RVG-M6 and 5.62 × 10³ for the RVG-WT-PEG control. Two weeks after the fourth immunization, RVG-WT formulated with AS03 or MF59 induced significant neutralizing antibody responses compared with the control group (p < 0.0001 and p < 0.01, respectively). The neutralizing antibody titers reached 1:79.43 in the AS03 group and 1:33.11 in the MF59 group, whereas the WT-PEG + AS03 control group showed a low titer of 1:3.72. In contrast, RVG-M6 formulated with MF59 failed to induce detectable neutralizing antibodies (1:3.02). Furthermore, RVG-WT + AS03 induced significantly higher neutralizing antibody responses than the WT-PEG + AS03 control group (p < 0.0001), and a significant difference was also observed between the RVG-WT + MF59 and RVG-M6 + MF59 groups (p < 0.01). Conclusions: The glycoengineered Pichia pastoris expression system successfully produced uniform full-length rabies virus glycoprotein nanoparticles with high purity. When formulated with the AS03 adjuvant, RVG-WT induced high-titer neutralizing antibodies in mice, suggesting a promising strategy for the development of recombinant subunit vaccines against rabies. However, this study is limited by the absence of challenge studies and validation in target animal species, which will be further investigated in future work. Full article

Canine distemper virus (CDV) affects both domestic and wild carnivores and is associated with a high mortality rate. The virus can cross species barriers, infecting a wide range of mammals, which raises concerns for both wildlife conservation and domestic animal health. During our study, we processed a total of n = 552 oral and rectal swab samples from n = 260 red foxes (Vulpes vulpes) and n = 16 golden jackals (Canis aureus). The samples were collected by the National Food Chain Safety Office (NÉBIH) as part of a Rabies monitoring programme from Hungary in 2024. We performed a Real-Time RT-PCR, followed by a CDV-specific amplicon-based sequencing method using Oxford Nanopore Technologies to obtain the complete genome. All golden jackal samples tested negative, while both oral and rectal samples of one red fox tested positive for viral RNA. From this positive sample, we were able to sequence a partial CDV genome. Based on phylogenetic analysis of the haemagglutinin gene, our CDV sequence was assigned to the Europe lineage, one of the endemic lineages in the continent, infecting both threatened and common animals. This finding highlights the ongoing presence of CDV in wildlife populations and illustrates the value of integrated monitoring systems. Full article

The prevention of trichinellosis is one of the most important tasks of the public veterinary services. In most EU countries, mandatory testing for parasites of the genus Trichinella includes domestic pigs as well as game species such as wild boar and bears. In Croatia, hunters occasionally also submit badger (Meles meles) meat for Trichinella testing. In addition to the samples from the genus Meles, samples from two other genera within the same family, Martes and Mustela, were analysed. These specimens were most frequently delivered to the laboratory, as roadkill, within a passive surveillance program for the rabies virus. During a 14-year study period, muscle samples from 40 badgers (M. meles), 11 martens (M. foina) and from one polecat (M. putorius) were examined using the artificial digestion method. Trichinella infection was confirmed in four badgers (10%) and one marten (9.1%). Molecular identification by multiplex PCR revealed T. spiralis and T. britovi in two badger specimens, while T. pseudospiralis was identified in a stone marten. Further genetic analysis of the T. pseudospiralis isolate demonstrated its belonging to the Palaearctic population. This study evaluates the epidemiological significance of these findings in relation to trichinellosis, the most important foodborne parasitosis in Croatia, and emphasizes the need for further epidemiological studies in the country targeting both Mustelidae and T. pseudospiralis in the sylvatic cycle of Trichinella. Full article

Rabies virus (RABV) causes fatal encephalitis once it invades the central nervous system (CNS), and treatment options are extremely limited at this stage. We investigated the recombinant RABV variants SPBN, SPBNGA (glycoprotein substitution R333E), SPBNGAK (R333E plus N194K), SPBNGAS (R333E plus N194S), and TriGAS (three copies of the R333E/N194S glycoprotein). We evaluated their cellular tropism and immune activation in an intracerebral mouse infection model using immunohistochemistry and confocal immunofluorescence. SPBNGAK (R333E/N194K) resulted in mixed neuronal and astrocytic infection and lethal disease. In contrast, the R333E/N194S mutations in the GAS variants were associated with reduced neuronal infection and apparent astrocyte-restricted infection patterns. This tropism shift coincided with microglial activation (allograft inflammatory factor 1, amoeboid transformation) and astrocytic activation (nestin), along with T-cell infiltration and endothelial activation that persisted beyond viral clearance. SPBNGAK-infected astrocytes expressed nestin, while GAS variant-infected astrocytes remained nestin-negative and were rapidly cleared. Intracerebral co-inoculation of astrocytotropic TriGAS with the lethal neurotropic DOG4 strain was associated with survival and a marked reduction in detectable DOG4 neuronal infection. These findings suggest that glycoprotein-mediated astrocyte tropism may be associated with altered immune responses after rabies CNS invasion. While mechanistic causality cannot be inferred, these observations may inform the design of future studies exploring astrocyte-restricted RABV infection in therapeutic-related contexts. Full article

Rabies is an acute and fatal zoonotic disease caused by the rabies virus, responsible for approximately 59,000 deaths worldwide each year. Once clinical symptoms manifest, the case fatality rate approaches 100%. Vaccination remains the only effective strategy for prevention and control. Currently, human rabies vaccines approved by regulatory authorities such as the U.S. Food and Drug Administration (FDA), and the China National Medical Products Administration (NMPA) are all inactivated, adjuvant-free formulations. These vaccines are associated with several limitations, including weak immunogenicity, delayed induction of neutralizing antibodies, complex immunization schedules, and poor patient compliance. Adjuvants, as nonspecific immunoenhancers, can potentiate the immune response even at low antigen doses and reduce the number of required doses, offering a promising approach to overcome the aforementioned challenges. This article reviews recent advances in adjuvants suitable for rabies vaccines and discusses the key challenges currently faced in the development of adjuvanted rabies vaccines. Full article

Background: Lentiviral vectors (LVs) show promise as gene therapy tools for brain tumors, but optimal envelope protein choices for different tumor types have not been determined. Methodology: This study evaluated three pseudotyped LV variants—VSV-GP, FuG-B2, and LCMV-GP—across diverse brain tumor cell lines including glioblastoma (GBM), diffuse intrinsic pontine glioma (DIPG), medulloblastoma, and metastatic brain cancers. Results: VSV-GP and FuG-B2 pseudotypes significantly outperformed LCMV-GP across most tumor types. Both VSV-GP and FuG-B2 demonstrated high transduction efficiency in GBM and DIPG cells, though some cell lines displayed selective preferences for one pseudotype over the other. Medulloblastoma cells were challenging to transduce, with only VSV-GP achieving substantial efficacy. Metastatic brain cancers showed distinct tropism patterns: melanoma metastases were preferentially transduced by the FuG-B2 pseudotype, while lung metastases showed preference for the VSV-GP pseudotype. Conclusions: These findings suggest envelope protein selection should be tailored to specific brain tumor types. VSV-GP appears most suitable for medulloblastoma and lung metastases, FuG-B2 for melanoma metastases, and both for GBM and DIPG gene therapy applications. The study provides crucial guidance for translating lentiviral gene therapy to clinical applications, supporting personalized treatment strategies based on tumor-specific vector tropism profiles. Full article

Rabies is a neglected tropical zoonotic disease caused by rabies-virus (RV) infection and is responsible for almost 60,000 annual deaths globally, largely affecting the socio-economically disadvantaged population. Although fatality is preventable by immunization either before or after exposure with therapeutic antibodies, the high cost of prophylaxis or treatment limits their accessibility for the affected population. However, due to the almost 100% fatality rate in symptomatic individuals, almost 29 million annual vaccinations are performed, imposing high financial burden. Human transmission occurs principally through bites from infected dogs and although multiple mammalian species are permissive to RV, transmission from them or from symptomatic humans is rare. To overcome the limitations posed by the requirement of biosafety level-3 (BSL-3) containment for live virus culture, we established a replication-deficient vesicular stomatitis virus (VSV) pseudovirus expressing the Rabies-G (RV-G) protein and a multiplexed Luminex immunoassay for quantifying anti-rabies antibodies in equine sera. The purified pseudovirus exhibited robust luciferase activity and was able to infect multiple mammalian cell lines, although with variable efficiency. Using hyper-immunized equine serum, we observed a strong correlation (ρ > 0.9, p < 0.001) between binding antibody titers measured by the Luminex assay with neutralizing antibody titers determined using the pseudovirus-based neutralization assay. These assays provide a safe, quantitative, and BSL-2-compatible platform for rabies serological evaluation and vaccine testing. Full article

Background: Madariaga virus (MADV), formerly known as the South American variant of Eastern Equine Encephalitis virus (EEEV), is an alphavirus that belongs to the Togaviridae family and has been periodically infecting equids in Venezuela since its first identification in 1975. This study reports the isolation and molecular characterization of MADV isolated from a horse in December 2024 in the context of MADV cases reported in Venezuela. Methods: Antibodies to the rabies virus were detected by indirect immunofluorescence, and to the Equine Infectious Anemia virus (EIAV) by passive immunodiffusion. MADV RNA was detected by qRT-PCR. The sequence of the complete viral genome was obtained by next-generation sequencing. Results: The sequence of this virus was highly similar to that of the only human case of MADV reported in the country in 2016, as well as to a sequence of a virus isolated from a horse in Colombia in 2002. The horse was found to be co-infected with EIAV. Conclusions: The continuous circulation of MADV in Venezuela warrants reinforcing the preventive measures against these alphaviruses, which ignore borders, and may cause important animal and human health concerns. Full article