Search Results (126)

Enteroviruses of the Picornaviridae family are transmitted primarily by the fecal–oral route. Transmission may occur following hand contact with contaminated fomites and subsequent ingestion of virus conveyed to the mouth by the contaminated hand. The persistence of these viruses on fomites likely plays a role in this transmission scenario. Six echoviruses (1, 2, 3, 5, 6, and 7) that cause frequently reported clinical cases in the United States were studied, along with poliovirus type 1 vaccine strain LSc-2ab. The infectivity half-lives of the enteroviruses deposited on vinyl tile coupons in a 10% fecal solution ranged from 1.7 to 12.6 h. The echovirus serotypes most commonly associated with reported infections persisted longer on the vinyl tiles than the less commonly reported types. This increased persistence on surfaces may favor the transmission of these echoviruses through the fecal–oral route. These results inform the future selection of appropriate model enteroviruses for challenging newly formulated and eco-friendly disinfectants or other strategies in infection prevention and control for enteroviruses. Full article

Background: Enteroviruses, members of the Picornaviridae family, typically cause asymptomatic or mild infections. However, they can also result in central nervous system (CNS) involvement, with transverse myelitis (TM) occurring only on rare occasions. TM is a syndrome characterized by acute or subacute spinal cord dysfunction, leading to neurological deficits below the level of the lesion. Case report: We report a case series of eight pediatric patients admitted over a three-month period, June to August 2024. All patients presented with ataxia and/or other neurological symptoms, alongside abnormal cerebrospinal fluid (CSF) findings. Although ataxia is commonly associated with cerebellitis, magnetic resonance imaging (MRI) in this cohort revealed findings consistent with TM. Notably, all patients demonstrated similar MRI abnormalities. The onset of symptoms occurred over a short time during an enterovirus epidemic. Enteroviral RNA was detected, or the virus was isolated in seven patients, while one patient had a close epidemiological link to the virus. All patients achieved full recovery following immunomodulatory therapy. Conclusions: This case series underscores that ataxia may be an atypical symptom associated with TM. Furthermore, there was a notable distinction between the clinical presentation and neuroradiological findings. Immunomodulatory therapy with immunoglobulins and corticosteroids has been shown to be effective and safe, supporting the hypothesis of an immune-mediated pathogenesis in these patients. Full article

Since its discovery via metagenomics in 2008, human cosavirus (HCoSV) has been detected in the cerebrospinal fluid (CSF) and feces of humans with meningitis, acute flaccid paralysis (AFP), and acute gastroenteritis. To date, 34 HCoSV genotypes have been documented by the Picornaviridae study group. However, the documented genetic diversity of HCoSV in Nigeria is limited. Here we describe the genetic diversity of HCoSV in Nigeria using a metagenomics approach. Archived and anonymized fecal specimens from children (under 15 years old) diagnosed with non-polio AFP from five states in Nigeria were analyzed. Virus-like particles were purified from 55 pools (made from 254 samples) using the NetoVIR protocol. Pools were subjected to nucleic acid extraction and metagenomic sequencing. Reads were trimmed and assembled, and contigs classified as HCoSV were subjected to phylogenetic, pairwise identity, recombination analysis, and, when necessary, immuno-informatics and capsid structure prediction. Fifteen pools yielded 23 genomes of HCoSV. Phylogenetic and pairwise identity analysis showed that all belonged to four species (eleven, three, three, and six members of Cosavirus asiani, Cosavirus bepakis, Cosavirus depakis, and Cosavirus eaustrali, respectively) and seventeen genotypes. Ten genomes belong to seven (HCoSV-A3/A10, A15, A17, A19, A24, D3, and E1) previously assigned genotypes, while the remaining thirteen genomes belonged to ten newly proposed genotypes across the four HCoSV species, based on the near-complete VP1 region (VP1*) of the cosavirus genome. Our analysis suggests the existence of at least seven and eight Cosavirus bepakis and Cosavirus eaustrali genotypes, respectively (including those described here). We report the first near-complete genomes of Cosavirus bepakis and Cosavirus depakis from Nigeria, which contributes to the increasing knowledge of the diversity of HCoSV, raising the number of tentative genotypes from 34 to over 40. Our findings suggest that the genetic diversity of HCoSV might be broader than is currently documented, highlighting the need for enhanced surveillance. Full article

Viral infections have been associated with multiple sclerosis (MS), an immune-mediated disease in the central nervous system (CNS). Since Theiler’s murine encephalomyelitis virus (TMEV) can induce MS-like demyelination, TMEV infection is the most widely used viral model for MS. Although the precise pathophysiology is unknown, altered fecal bacterial populations were associated with distinct immune gene expressions in the CNS. We aimed to determine the role of gut microbiota in TMEV infection by administering an antibiotic cocktail in drinking water before (prophylactic administration) or after (therapeutic administration) TMEV infection. The antibiotic administration reduced total eubacteria, including the phyla Bacillota and Bacteroidota, but increased the phylum Pseudomonadata in feces. Prophylactic administration did not alter TMEV-induced inflammatory demyelination clinically or histologically, without changes in anti-viral IgG1/IgG2c levels or lymphoproliferative responses; therapeutic administration temporarily suppressed the neurological signs. Although antibiotic treatment had minimal effects on TMEV infection, adding metronidazole and ampicillin in drinking water substantially reduced water intake in the antibiotic group of mice, resulting in significant body weight loss. Since dehydration and stress could affect immune responses and gut microbiota, caution should be exercised when planning or evaluating the oral antibiotic cocktail treatment in experimental animals. Full article

Rodents represent the most diverse order of mammals, comprising over 2200 species and nearly 42% of global mammalian biodiversity. They are major reservoirs of zoonotic pathogens, including viruses, bacteria, protozoa, and fungi, and are particularly effective at transmitting diseases, especially synanthropic species that live in close proximity to humans. As of April 2025, approximately 15,205 rodent-associated viruses have been identified across 32 viral families. Among these, key zoonotic agents belong to the Arenaviridae, Hantaviridae, Picornaviridae, Coronaviridae, and Poxviridae families. Due to their adaptability to both urban and rural environments, rodents serve as efficient vectors across diverse ecological landscapes. Environmental and anthropogenic factors, such as climate change, urbanization, deforestation, and emerging pathogens, are increasingly linked to rising outbreaks of rodent-borne diseases. This review synthesizes current knowledge on rodent-borne viral zoonoses, focusing on their taxonomy, biology, host associations, transmission dynamics, clinical impact, and public health significance. It underscores the critical need for early detection, effective surveillance, and integrated control strategies. A multidisciplinary approach, including enhanced vector control, improved environmental sanitation, and targeted public education, is essential for mitigating the growing threat of rodent-borne zoonoses to global health. Full article

In the mid-1970s, it was revealed that the 5′ end of the RNA genome of poliovirus (PV) was covalently linked to a peptide called VPg (viral protein, genome-linked). Subsequently, VPgs have been found attached to many other viruses and even phages. This review summarizes the patterns of physicochemical properties that are conserved within the VPgs of plus-strand RNA viruses where short-peptide VPgs have been identified. Mutagenesis and structural data indicate the importance of a 5 aa conserved motif at the N-termini of picornaviral VPgs (around the tyrosine 3 residue, which forms a covalent bond to UMP and the RNA). Hidden Markov models have been used to find motifs and VPgs in additional genera of picornaviruses, as well as dicistroviruses in insects and comoviruses in plants. These latter VPgs are bound to the RNA termina through linkages to serine or threonine. The role of free VPg and VPgpU needs clarification, especially in light of multiple genome copies in many of the viruses. Lysine and other positively charged side chains are hallmarks of VPgs. These may contribute to interactions with the viral RNA, polymerase, membranes and cellular proteins. The larger protein VPgs from potyviruses and noroviruses/caliciviruses may also show some areas of similar properties to these small peptides. Full article

Human enterovirus 71 (EV-A71), a member of the Picornaviridae family, is predominantly associated with hand, foot, and mouth disease in infants and young children. Additionally, EV-A71 can cause severe neurological complications, including aseptic meningitis, brainstem encephalitis, and fatalities. The molecular mechanisms underlying these symptoms are complex and involve the viral tissue tropism, evasion from the host immune responses, induction of the programmed cell death, and cytokine storms. This review article delves into the EV-A71 life cycle, with a particular emphasis on recent advancements in understanding the virion structure, tissue tropism, and the interplay between the virus and host regulatory networks during replication. The comprehensive review is expected to contribute to our understanding of EV-A71 pathogenesis and inform the development of antiviral therapies and vaccines. Full article

Rhinoviruses and respiratory enteroviruses remain among the leading causes of acute respiratory infections, particularly in children. Little is known about the genetic diversity of enteroviruses and rhinoviruses in pediatric patients with acute respiratory infections in Russia. We assessed the prevalence of human rhinoviruses/enteroviruses (HRV/EV) in 1992 children aged 0 to 17 years hospitalized with acute respiratory infections during the 2023–2024 epidemic season using PCR. The detection rate of HRV/EV was 11% (220/1992). We performed typing of 58 HRV and 28 EV viruses by partial sequencing of the VP1 gene. Rhinovirus A was the most common among HRV, followed by rhinovirus C; rhinovirus B was detected in only three cases. Enteroviruses were represented by all four species, with the EV-D68 genotype being the most frequently detected. Phylogenetic analysis of the VP1 fragment of EV-D68 showed that all our sequences belonged to the B3 subclade. We identified the first case of EV-C105 infection in Russia in a two-year-old girl hospitalized with pneumonia. Phylogenetically, the Novosibirsk strain EV-C105 was closely related to a strain discovered in France in 2018. This research helped to fill a critical gap in understanding the epidemiological landscape of HRV/EV in pediatric populations within Russia. Full article

Porcine stool-associated RNA virus (Posavirus) is an unclassified virus with sequence similarity to viruses in the order of Picornaviridae. In China, lineage 1 Posavirus (Posavirus 1) has been circulating in the field since its initial emergence in 2014 however no other lineages have been reported. To investigate the genetic diversity of Posavirus in China, 1200 diarrheic samples were collected from pigs in China. Following high-throughput and Sanger sequencing, one complete genome sequence of a Posavirus (designated SC01) strain was obtained. The genome of SC01 strain was 10217 nucleotides in length and encoded a polyprotein of 3346 amino acids. Genome comparative analysis revealed that SC01 shared 85.6% nucleotide similarity to Posavirus 2 strains, but only 35.2–58.0% sequence identity with Posavirus 1 and 3–12 strains. Phylogenetic analysis showed that the SC01 was classified in Posavirus 2 and clustered into a separate branch with the American Posavirus 2 isolates, indicating that the SC01 is a Posavirus 2 strain. Notably, a novel 1-amino acid deletion was observed in polyprotein at amino acid position 147. This is the first report of the presence of Posavirus 2 in China, and the genomic data of SC01 provides insights into the genetic diversity and evolution of Posavirus in the region. Full article

Kobuviruses (KoVs) are a group of small, non-enveloped RNA viruses classified in the genus Kobuvirus within the Picornaviridae family, comprising Aichivirus species A to F. KoVs have been identified in humans and several mammals, including domestic ungulates. This study investigated the presence of KoVs in a collection of bovine stool samples (n = 38) obtained from animals with enteritis or without clinical signs. By RT-PCR screening, KoV RNA was detected in 10/38 animals (26.3%). Six of the ten positive animals had enteric signs. On sequence analysis of the amplicons, eight strains were related to species Aichivirus B, commonly identified in cattle. In contrast, two strains (ITA/2019/572-1 and ITA/2020/bovine/30-2), displayed the highest nt identity (up to 97.1%) to cattle, yak, and goat Aichivirus D strains. On whole genome analysis, strains ITA/2019/572-1 and ITA/2020/30-2 showed 88.9% nt identity to each other and 87.8–90.3% nt to the bovine kobuvirus strain CHN/2021/ON730709 identified in China. Interestingly these three Aichivirus D strains showed a recombinant makeup, clustering with D1 genotype in the capsid region and with D2 genotype in the non-structural genes. These findings suggest that Aichivirus D KoVs are common components of livestock virome. Understanding the genetic diversity of KoVs in animals will be useful to improve the diagnostics and gather epidemiological data. Full article

One of the major factors hindering efficient livestock production is the presence of high-impact infectious animal diseases, such as foot and mouth disease (FMD), lumpy skin disease (LSD), and bovine ephemeral fever (BEF), which are notable viral infections affecting cattle in Egypt, leading to significant economic losses. FMD is caused by the foot and mouth disease virus (FMDV) of the genus Aphthovirus in the Picornaviridae family. LSD is caused by lumpy skin disease virus (LSDV) of Capripox genus within the Poxviridae family, subfamily Chordopoxvirinae. BEF is caused by bovine ephemeral fever virus (BEFV) of genus Ephemerovirus in the Rhabdoviridae family. FMD is a highly contagious viral infection of domestic and wild cloven-hooved animals and can spread through the wind. On the other hand, LSD and BEF are arthropod-borne viral diseases that mainly affect domestic cattle and water buffalo. Despite government vaccination efforts, these three viral diseases have become widespread in Egypt, with several reported epidemics. Egypt’s importation of large numbers of animals from different countries, combined with unregulated animal movements through trading and borders between African countries and Egypt, facilitates the introduction of new FMDV serotypes and lineages not covered by the current vaccination plans. To establish an effective control program, countries need to assess the real epizootic situation of various infectious animal diseases to develop an efficient early warning system. This review provides information about FMD, LSD, and BEF, including their economic impacts, causative viruses, global burden, the situation in Egypt, and the challenges in controlling these diseases. Full article

Background: Hepatitis A virus (HAV) infection is a significant global cause of viral hepatitis. At present, the anti-HAV vaccine in Italy is proposed exclusively for specific high-risk groups, and a universal vaccination program is not implemented. Objectives: This study aimed to assess the level of immunity against HAV in patients of both sexes across age groups ranging from 0 to 95 years admitted to the San Giovanni di Dio e Ruggi d’Aragona Hospital in Salerno, Italy, over a 9-year period (2015–2023). Methods: The total HAV seroprevalence by chemiluminescence Vitros system immunodiagnostics (ortho-diagnostics) was obtained by database analysis, stratifying patients for gender and age group in both the pre-pandemic (2015–2019) and pandemic (2020–2023) periods. Results: Out of 28,104 samples collected in 2015–2023, 20,613 resulted positive by total HAV immune screening, with a significant reduction in the annualized proportion of events during the pandemic period compared to the pre-pandemic period. HAV was more abundant in males than females in both periods (exceeding the 70%), with a statistically significant decrease in HAV in females in 2015–2019. The 61–70-year-old age group is more susceptible for both genders, with a strong deviation from the 41–50-year-old age group compared to the 51–60-year-old group. The pandemic period affected the number of analyzed samples in 2020. Conclusions: The study revealed high HAV seroprevalence, especially in males and individuals aged 61–70 years. There was a notable decrease in seroprevalence during the pandemic compared to pre-pandemic years. These results emphasize the need for ongoing monitoring and suggest that a universal vaccination program could address regional immunity gaps and lower disease incidence. Full article

Shrews (Soricidae) are common small wild mammals. Some species of shrews, such as Asian house shrews (Suncus murinus), have a significant overlap in their habitats with humans and domestic animals. Currently, over 190 species of viruses in 32 families, including Adenoviridae, Arenaviridae, Arteriviridae, Astroviridae, Anelloviridae, Bornaviridae, Caliciviridae, Chuviridae, Coronaviridae, Filoviridae, Flaviviridae, Hantaviridae, Hepadnaviridae, Hepeviridae, Nairoviridae, Nodaviridae, Orthoherpesviridae, Orthomyxoviridae, Paramyxoviridae, Parvoviridae, Phenuiviridae, Picobirnaviridae, Picornaviridae, Polyomaviridae, Poxviridae, Rhabdoviridae, Sedoreoviridae, Spinareoviridae, and three unclassified families, have been identified in shrews. Diverse shrew viruses, such as Borna disease virus 1, Langya virus, and severe fever with thrombocytopenia syndrome virus, cause diseases in humans and/or domestic animals, posing significant threats to public health and animal health. This review compiled fundamental information about shrews and provided a comprehensive summary of the viruses that have been detected in shrews, with the aim of facilitating a deep understanding of shrews and the diversity, epidemiology, and risks of their viruses. Full article

Avian encephalomyelitis (AE) is a disease caused by the avian encephalomyelitis virus (AEV) of the genus Tremovirus in the family Picornaviridae. Recently, cases of turkey poults showing neurological signs were submitted to the veterinary diagnostic laboratories at South Dakota State University and the University of Minnesota. The affected birds were showing nervous neurological signs such as tremors, inability to stand, torticollis, and wing drop. Clinical signs were observed by 3 weeks of age. Necropsy of birds revealed no significant gross lesions in the internal organs, including the brain. There was no significant bacterial growth in the brains. Microscopic examination of various sections of the brain revealed multifocal lymphocplasmacytic perivascular cuffs in the cerebellum and cerebral cortex. The brain samples were processed for detection and whole genome sequencing by next-generation sequencing. Three full-length polyprotein sequences (6405 nt) of AEV were assembled. All three sequences shared 99.9–100% nucleotide and 100% amino acid identities with each other. Only 77.7–78.5% of nucleotide and 90.3–92.5% of amino acid identities with AEV field strains and vaccine sequences were available in GenBank. This indicates that a new divergent variant of AEV is circulating in the field and causing AE outbreaks in the Midwest region. Full article

Hepatitis A virus (HAV) is an enteric virus mainly transmitted by the faecal–oral route. Belonging to the Picornaviridae family, HAV was first described as small naked particles, like all viruses of this family. However, for about a decade, it was demonstrated that HAV particles can exist surrounded by a lipid bilayer. This type of particle, called enveloped HAV (eHAV), acquires its lipid bilayer by hijacking a part of cell membranes during the virion egress in the last steps of the viral cycle. In vitro culture systems produce mainly eHAV, and so, to date, most of the studies on HAV have been carried out using this type of viral particle. In this study, a method based on lipid bilayer removal by chemical delipidation is proposed for the production of naked HAV particles. The resulting naked HAV particles conserve their infectivity and are therefore fully cultivable in vitro. By using this method, naked HAV particles can easily be produced in vitro and can be useful to perform further studies such as inactivation processes for the food industry, as HAV is a main concern for food safety. Full article