Search Results (302)

Type 1 diabetes mellitus (T1DM) is a chronic autoimmune disorder characterized by the destruction of insulin-producing pancreatic beta cells, resulting in lifelong insulin dependence. While genetic susceptibility—particularly human leukocyte antigen (HLA) class II alleles—is a major risk factor, accumulating evidence implicates viral infections as potential environmental triggers in disease onset and progression. This narrative review synthesizes current findings on the role of viral pathogens in T1DM pathogenesis. Enteroviruses, especially Coxsackie B strains, are the most extensively studied and show strong epidemiological and mechanistic associations with beta-cell autoimmunity. Large prospective studies—including Diabetes Virus Detection (DiViD), The environmental determinans of diabetes in the young (TEDDY), Miljøfaktorer i utvikling av type 1 diabetes (MIDIA), and Diabetes Autoimmunity Study in the Young (DAISY)—consistently demonstrate correlations between enteroviral presence and the initiation or acceleration of islet autoimmunity. Other viruses—such as mumps, rubella, rotavirus, influenza A (H1N1), and SARS-CoV-2—have been investigated for their potential involvement through direct cytotoxic effects, immune activation, or molecular mimicry. Interestingly, certain viruses like varicella-zoster virus (VZV) and cytomegalovirus (CMV) may exert modulatory or even protective influences on disease progression. Proposed mechanisms include direct beta-cell infection, molecular mimicry, bystander immune activation, and dysregulation of innate and adaptive immunity. Although definitive causality remains unconfirmed, the complex interplay between genetic predisposition, immune responses, and viral exposure underscores the need for further mechanistic research. Elucidating these pathways may inform future strategies for targeted prevention, early detection, and vaccine or antiviral development in at-risk populations. Full article

Enteric diseases represent one of the main causes of morbidity and mortality in poultry production, especially in turkeys (Meleagris gallopavo), significantly affecting the profitability of the sector. Turkey enteric complex (PEC) is a multifactorial syndrome characterized by diarrhea, stunting, poor feed conversion, and increased mortality in young turkeys. Its aetiologia includes multiple avian enteric viruses, including astrovirus, rotavirus, reovirus, parvovirus, adenovirus, and coronavirus, which can act singly or in co-infection, increasing clinical severity. This study performs a systematic review of the literature on these viruses and a meta-analysis of their prevalence in different regions of the world. Phylogenetic analyses were used to assess the genetic diversity of the main viruses and their geographical distribution. The results show a wide regional and genetic variability, which underlines the need for continuous epidemiological surveillance. Health and production implications are discussed, proposing control strategies based on biosecurity, targeted vaccination, and optimized nutrition. These findings highlight the importance of integrated management to mitigate the impact of CSF in poultry. Full article

CrAssphage, a bacteriophage that infects human gut-associated Bacteroides spp., has emerged as a potential anthropogenic fecal pollution indicator in environmental matrices. This study investigated the presence and concentration of crAssphages in bivalve mollusks (oysters and mussels) marketed in three cities in the state of Rio de Janeiro, Brazil, sampled from January to December 2022. CrAssphages were detected during the study period in 66.7% (48/72) of sampled oysters and 54.8% (34/62) of sampled mussels, at median concentrations of 1.9 × 10⁴ and 4.2 × 10⁴ genome copies (GC)/g, respectively. These levels were 1–2 log₁₀ higher than those observed for major human enteric viruses, including norovirus genogroups GI and GII, sapovirus, human mastadenovirus (HAdV), rotavirus A, human astrovirus (HAstV), and hepatitis A virus. CrAssphage specificity and sensitivity were calculated for all viruses. Moderate correlations between crAssphage (log₁₀ GC/g) and norovirus GI and GII, HAdV, SaV, and HAstV (Spearman’s rho = 0.581–0.464, p < 0.001) were observed in mussels. Altogether, the data support the use of crAssphage as a molecular indicator of human viral contamination in shellfish, with potential application in routine environmental and food safety monitoring in production areas. Full article

Porcine rotavirus (PoRV), a primary etiological agent of viral diarrhea in piglets, frequently co-infects with other enteric pathogens, exacerbating disease severity and causing substantial economic losses. Its genetic recombination capability enables cross-species transmission potential, posing public health risks. Globally, twelve G genotypes and thirteen P genotypes have been identified, with G9, G5, G3, and G4 emerging as predominant circulating strains. The limited cross-protective immunity between genotypes compromises vaccine efficacy, necessitating genotype surveillance to guide vaccine development. While conventional molecular assays demonstrate sensitivity, they lack rapid genotyping capacity and face technical limitations. To address this, we developed a novel diagnostic platform integrating reverse transcription recombinase-aided amplification (RT-RAA) with CRISPR–Cas12a. This system employs universal primers for the simultaneous amplification of G4/G5/G9 genotypes in a single reaction, coupled with sequence-specific CRISPR recognition, achieving genotyping within 50 min at 37 °C with 10⁰ copies/μL sensitivity. Clinical validation showed a high concordance with reverse transcription quantitative polymerase chain reaction (RT-qPCR). This advancement provides an efficient tool for rapid viral genotyping, vaccine compatibility evaluation, and optimized epidemic control strategies. Full article

Mucosal immunization represents a promising strategy for preventing enteric infections. Rotavirus (RV), a leading gastrointestinal pathogen distinguished by its remarkable stability and segmented double-stranded RNA genome, has been engineered into a versatile oral vaccine vector through advanced reverse genetics systems. The clinical efficacy of live-attenuated RV vaccines highlights their unique capacity to concurrently induce mucosal IgA responses and systemic neutralizing antibodies, positioning them as a multiple action vector for multiple immune protection. In this review, we summarize the RV colonization of the intestine and stimulation of intestinal immunity, as well as recent advancements in RV reverse genetics, and focus on their application in the rational design of a multivalent mucosal vaccine vector targeting enteric pathogens considering the advantages and challenges of RV as a vector. We further propose molecular strategies to overcome genetic instability in recombinant RV vectors, including the codon optimization of heterologous inserts. These insights provide a theoretical foundation for developing next-generation mucosal immunization platforms with enhanced safety, stability, and cross-protective efficacy. Full article

Background: Acute viral gastroenteritis (AVG) still has an impact on children under 5 years old in developing countries. In Romania, vaccination against Rotavirus is not included in the National Immunization Program. Children from poor social backgrounds represent 48% of the patients hospitalized in Children’s Clinical Hospital of Brasov. The use of antibiotics in Romania is high. Methods: The retrospective study enrolled 1054 children, 0–48 months of age, hospitalized in the Emergency Clinical Hospital for Children Brasov between January 2022–December 2023, for Rotavirus, Adenovirus or Norovirus acute gastroenteritis. Children presenting nosocomial infections were excluded. All children that have met the previously mentioned criteria, presenting positive stool samples (immunochromatography method) for Rotavirus, Adenovirus or Norovirus were included in the study. Results: Out of 1054 cases of AVG 782 (74.2%) were due to Rotavirus, 196 (18.5%) to Adenovirus and 76 (7.3%) to Norovirus. A total of 477 (45.3%) patients came from poor social backgrounds and 577 (54.7%) children from good social backgrounds. Rotavirus infection was equally prevalent in both groups (p < 0.35). Children from poor social backgrounds presented an average age of 11 months (SD ± 9; range 14 days–48 months) and a hospitalization average of 5.86 days (SD ± 3.67; range 1–22 days) compared to the others, who presented an average of 21 months (SD ± 15; range 26 days–48 months) and hospitalization average of 5.20 days (SD ± 2.51; range 1–18 days) (p < 0.01; p < 0.01). Severe dehydration presented 267 children from poor settings (56%) and 186 (17.6%) received antibiotics, compared to the other group—224 children (38.8%) with severe dehydration and 216 (20.4%) receiving antibiotics. The most used antibiotic for both groups was Ceftriaxone (53.9% and 57.6% of all AVG). Conclusions: Rotavirus is the leading AVG cause. Children from poor backgrounds were younger, more dehydrated, hospitalized longer. Full article

Group A rotavirus (RV) causes gastrointestinal disease in infants worldwide, and there is currently no specific treatment to eliminate the virus. Due to its chemical properties, propolis is a promising compound for improving gastrointestinal infections. This study aimed to evaluate the action of stingless bee propolis against RV. The method involved determining the concentrations of the extracts that do not exhibit cytotoxicity in colon adenocarcinoma cells using the MTT assay and measuring the reduction in infectivity through a focus forming assay. The results showed that stingless bee propolis was non-cytotoxic up to 200 µg/mL. The reduction in RV infectivity exceeded 99% when using propolis from Plebeia droryana and Melipona quadrifasciata. Brazilian stingless bee propolis, whose active components are known for their activity against various viruses, was experimentally tested and demonstrated effective antiviral activity against RV, supporting its potential application as an antiviral agent. Full article

Rotavirus alphagastroenteritidis (R. alphagastroenteritidis) remains the leading cause of pediatric diarrhea. Although Angola introduced Rotarix^®, the human monovalent R. alphagastroenteritidis vaccine since 2014 as part of its routine childhood immunization program, no follow-up study has been conducted. The aim of this study was to evaluate the distribution of R. alphagastroenteritidis genotypes among children under five years of age, hospitalized with acute gastroenteritis (AGE), after the introduction of the rotavirus vaccine. To achieve this goal, stool samples collected between 2021 and 2022 from children under 5 years of age diagnosed with AGE at six hospitals in Luanda Province were analyzed. The R. alphagastroenteritidis-antigen immunochromatographic test (SD Bioline™, Abbott, Chicago, IL, USA) was performed, and 121 positive samples were genotyped. Ten samples were randomly selected for further Sanger sequencing. The results showed that the G9P[6] was the most prevalent genotype (17.3%), followed by G9P[8] (16.5%), G2P[4] (14.9%), G3P[6] (13.2%), G8P[6] (11.5%), and less frequently G12P[8] (9.1%), G1P[6] (4.1%), and G1P[8] (2.5%). The genotype combinations G3P[6], G8P[6], and G12P[8] were detected for the first time in Luanda Province. In conclusion, the emergence of new genotype combinations supports the need for continuous surveillance to identify the trend in R. alphagastroenteritidis infection and the emergence of new strains circulating in Luanda Province in the post-vaccination period. Full article

Background/Objectives: Mild encephalitis/encephalopathy with reversible splenial lesion (MERS) is a rare neurological disorder primarily affecting pediatric patients but also observed in adults. The radiological hallmark of MERS is a reversible lesion in the splenium of the corpus callosum. Although MERS generally has a favorable prognosis, its variable presentation poses diagnostic challenges. This study examines the clinical variability, diagnostic hurdles, and outcomes of pediatric MERS cases. Methods: Our retrospective study included 19 pediatric patients (11 female and 8 males with an average age of 8.41 years) diagnosed with MERS between 2016 and 2024. Clinical data, including demographic characteristics, prodromal symptoms, neurological features, MRI findings, laboratory results, treatments, and outcomes, were analyzed. Results: Among the 19 patients, 84% were previously healthy, with the remaining 16% having pre-existing medical conditions. The most common prodromal symptoms were fever (68%), vomiting (47%), and diarrhea (32%). Neurological manifestations included seizures (26%), headache (21%), and drowsiness (21%), among others. In terms of etiology, infections were identified in 52% of the patients, with viral agents, particularly rotavirus, being the most common (40%). Hyponatremia was present in 63% of the cohort. The typical MRI splenial lesion underwent complete resolution in all patients. Treatment varied, with 53% of patients receiving electrolyte rehydration, and 21% receiving intravenous immunoglobulin or corticosteroids. All patients, but one, achieved full recovery. Discussion: This study reinforces the clinical heterogeneity of MERS in pediatric patients, emphasizing its favorable prognosis independently of presentation. Viral infections and hyponatremia were the most frequent etiologies. Full article

This study evaluated the prevalence of BRV infection and its impact on the health of dairy cows at different growth stages, with a particular focus on milk-fed calves. BRV was detected in rectal swabs via RT–qPCR. In the total sample of 2400 dairy cows examined at three farms, 103 (4.29%) were found to be positive for BRV. Similarly, of the 480 milk-fed calves, 70 (14.58%) were also found to be positive for BRV. Negative binomial regression analysis revealed that older farms had higher average BRV positivity rates than new farms did and that the BRV positivity rate was higher in autumn than in the other three seasons. Additionally, BRV positivity rates gradually decreased as calf age increased. In milk-fed calves, BRV positivity was positively correlated with morbidity and mortality and negatively correlated with ADG and ADGPR. These findings provide valuable insights for farm management, particularly for older farms, highlighting the detrimental effects of BRV infection on milk-fed calves and underscoring the importance of targeted control strategies to reduce BRV prevalence and optimize dairy production efficiency. Full article

Diarrhea is a common disease in sika deer. The causes of diarrhea in sika deer are complex and involve a variety of pathogens. Additionally, new virulent pathogens are continuously emerging, which poses a serious threat to deer’s health and particularly affects fawns’ survival rate. In the present study, feces samples were collected from fawns with diarrhea in Jilin Province, in the northeast of China. The viral communities were investigated using the metagenomic method. Viral metagenome data revealed that the viruses in the fecal samples were mainly from 21 families in 14 orders. The major viruses in high abundance were astrovirus, rotavirus, coronavirus, and bovine viral diarrhea virus. In addition, a large number of phages, which mainly belonged to the family Siphoviridae, were identified. Then, the known causative virus species were investigated via RT-qPCR. The results showed that the infection rates of bovine coronavirus, bovine rotavirus, and bovine viral diarrhea virus were 59.44%, 58.89%, and 21.67%, respectively, and mixed infections were commonly seen in the samples. A bovine rotavirus strain was successfully isolated from the positive samples. Whole-genome sequencing revealed that the genotype of the strain was G6-P[1]-I2-R2-C2-M2-A3-N2-T6-E2-H3, indicating the recombination of rotavirus. This study revealed the profiles and characteristics of viruses that cause sika deer diarrhea, which will be helpful for understanding diarrhea diseases in sika deer. Full article

Rotavirus (RV) is the most common cause of severe acute gastroenteritis (AGE) in children under five years of age. This review summarizes current knowledge on RV infections, with a particular focus on viral structure, pathophysiological mechanisms, and age-dependent clinical presentation. Special attention is given to systemic manifestations, including central nervous system involvement, autoimmune responses such as type 1 diabetes and celiac disease, and rare associations with biliary atresia. The mechanisms of RV-induced diarrhea and vomiting are discussed in detail. Clinical severity scoring systems—such as the Vesikari and Clark scales—and dehydration assessment tools—the Clinical Dehydration Scale (CDS) and the Dehydration: Assessing Kids Accurately (DHAKA) score—are compared. The review highlights differences in disease course between children under and over five years, emphasizing that RV is not limited to early childhood. A major section addresses the global effectiveness of vaccination programs, their role in reducing disease burden, coverage challenges, and decreased efficacy in low-income countries. Particular focus is placed on high-risk groups, including preterm and immunocompromised infants. Full article

Group A rotavirus continues to be a leading global etiological agent of severe gastroenteritis in young children under 5 years of age. The replication of this virus in the host is associated with the occurrence of Lewis antigens and the secretor condition. Moreover, histo-blood group antigens (HBGAs) act as attachment factors to the outer viral protein of VP4 for rotavirus. Therefore, in this study, we employed a metabolomic approach to reveal potential signature metabolic molecules and metabolic pathways specific to rotavirus P[8] strain infection (VP4 genotype), which is associated with the expression of HBGA combined secretor and Lewis (Le) phenotypes, specifically secretor/Le^(a+b+). Further integration of the achieved metabolomics results with lipidomic and proteomics metadata analyses was performed. Saliva samples were collected from children diagnosed as negative or positive for rotavirus P[8] strain infection (VP4 genotype), which is associated with the HBGA combined secretor/Le^(a+b+). A total of 22 signature metabolic molecules that were downregulated include butyrate, putrescine, lactic acid, and 7 analytes. The upregulated metabolic molecule was 2,3-Butanediol. Significant pathway alterations were also specifically observed in various metabolism processes, including galactose and butanoate metabolisms. Butyrate played a significant role in viral infection and was revealed to exhibit different reactions with glycerolipids, glycerophospholipids, sphingolipids, sterol lipids, and fatty acyls. Moreover, butyrate might interact with protein receptors of free fatty acid receptor 2 (FFAR2) and free fatty acid receptor 3 (FFAR3). The revealed metabolic pathways and molecule might provide fundamental insight into the status of rotavirus P[8] strain infection for monitoring its effects on humans. Full article

Bovine rotavirus (BRV) is one of the main pathogens that cause acute diarrhea in calves under one month of age. Passive immunization has been recognized as an effective way to prevent and treat BRV infection. Recent studies have shown that 10% of bovine antibodies possess an ultra-long CDR H3 domain, which has been shown to be the smallest antigen-binding domain. Due to the extremely small size of ultra-long CDR H3 antibodies, the phage display method was utilized to obtain ultra-long CDR H3 antibodies targeting BRV, providing a new approach for the prevention and/or treatment of BRV. Here, we report the preparation of BRV-specific bovine ultra-long CDR H3 antibodies obtained by constructing and screening a phage display library containing approximately 8.55 × 10⁹ individual clones. Through three rounds of bio-panning, we identified 92 candidate clones, of which 79 exhibited specific binding activity in phage ELISAs. The recombinant bovine ultra-long CDR H3 antibodies could specifically bind to BRV in ELISAs and cell immunofluorescence assays. The neutralizing activity was further confirmed through virus neutralization tests. In the calf model experiment, the recombinant bovine ultra-long CDR H3 antibodies could relieve the symptoms of diarrhea, reduce both the amount and duration of virus release, and increase the survival in calves experimentally infected with BRV. Therefore, BRV-specific bovine ultra-long CDR H3 antibodies could serve as an effective agent for the prevention and treatment of BRV infection. At the same time, the development of ultra-long CDR H3 antibodies using phage display screening technology provides a new approach for developing biological agents for the prevention and control of infectious diseases in bovines. Full article

Enteric pathogens remain a health threat for children in low-income countries. A single nucleotide polymorphism (SNP) in the FUT2 gene that precludes the expression of fucosyltransferase 2 has been reported to influence the susceptibility to rotavirus and norovirus infections. The aim of this study was to investigate the association between G428A at rs601338 (stop codon variant) in the FUT2 gene and a range of enteric pathogens in children under 5 years of age. Rectal swab samples from 668 children (median age 13.6 months, 51% males, 93% rotavirus vaccinated, 468 with diarrhea) from Rwanda were analyzed via PCR for pathogen detection and SNP genotyping. A FUT2 stop codon (‘non-secretor’ status) was found in 19% of all children. Rotavirus was detected in 5.3% of non-secretors compared with in 13% of secretors (OR = 0.39, p = 0.019). Rotavirus P[8] was the predominant genotype and was found in 2.3% of non-secretors compared with 8.8% of secretors (p = 0.009). There was no association with any other pathogen, including noroviruses, of which 2 of 14 GII.4 infections were detected among non-secretors. Thus, the FUT2 stop codon variant was associated with rotavirus but not with any other pathogen. Full article