-
The Veterinary Clinics of North... Aug 2022A number of viruses transmitted by biological vectors or through direct contact, air, or ingestion cause neurologic disease in equids. Of interest are viruses of the... (Review)
Review
A number of viruses transmitted by biological vectors or through direct contact, air, or ingestion cause neurologic disease in equids. Of interest are viruses of the Togaviridae, Flaviviridae, Rhabdoviridae, Herpesviridae, Bornaviridae, and Bunyaviridae families. Many are classified as arboviruses because they use arthropod vectors, whereas others are transmitted directly via ingestion, inhalation, or integument damage. The goal of this article is to provide an overview on pathophysiologic and clinical aspects of arboviruses of equine importance, including alphaviruses (Togaviridae) and flaviviruses (Flaviviridae).
Topics: Alphavirus; Animals; Arboviruses; Flavivirus; Horse Diseases; Horses
PubMed: 35953146
DOI: 10.1016/j.cveq.2022.04.004 -
Advances in Virus Research 2020Alphaviruses, members of the enveloped, positive-sense, single-stranded RNA Togaviridae family, represent a reemerging public health threat as mosquito vectors expand...
Alphaviruses, members of the enveloped, positive-sense, single-stranded RNA Togaviridae family, represent a reemerging public health threat as mosquito vectors expand into new geographic territories. The Old World alphaviruses, which include chikungunya virus, Ross River virus, and Sindbis virus, tend to cause a clinical syndrome characterized by fever, rash, and arthritis, whereas the New World alphaviruses, which consist of Venezuelan equine encephalitis virus, eastern equine encephalitis virus, and western equine encephalitis virus, induce encephalomyelitis. Following recovery from the acute phase of infection, many patients are left with debilitating persistent joint and neurological complications that can last for years. Clues from human cases and studies using animal models strongly suggest that much of the disease and pathology induced by alphavirus infection, particularly atypical and chronic manifestations, is mediated by the immune system rather than directly by the virus. This review discusses the current understanding of the immunopathogenesis of the arthritogenic and neurotropic alphaviruses accumulated through both natural infection of humans and experimental infection of animals, particularly mice. As treatment following alphavirus infection is currently limited to supportive care, understanding the contribution of the immune system to the disease process is critical to developing safe and effective therapies.
Topics: Alphavirus; Alphavirus Infections; Animals; Encephalitis Virus, Venezuelan Equine; Horses; Humans; Mice
PubMed: 32711733
DOI: 10.1016/bs.aivir.2020.06.002 -
Current Topics in Microbiology and... 2022Chikungunya virus (CHIKV) was discovered more than six decades ago, but has remained poorly investigated. However, after a recent outbreak of CHIK fever in both... (Review)
Review
Chikungunya virus (CHIKV) was discovered more than six decades ago, but has remained poorly investigated. However, after a recent outbreak of CHIK fever in both hemispheres and viral adaptation to new species of mosquitoes, it has attracted a lot of attention. The currently available experimental data suggest that molecular mechanisms of CHIKV replication in vertebrate and mosquito cells are similar to those of other New and Old World alphaviruses. However, this virus exhibits a number of unique characteristics that distinguish it from the other, better studied members of the alphavirus genus. This review is an attempt to summarize the data accumulated thus far regarding the molecular mechanisms of alphavirus RNA replication and interaction with host cells. Emphasis was placed on demonstrating the distinct features of CHIKV in utilizing host factors to build replication complexes and modify the intracellular environment for efficient viral replication and inhibition of the innate immune response. The available data suggest that our knowledge about alphavirus replication contains numerous gaps that potentially hamper the development of new therapeutic means against CHIKV and other pathogenic alphaviruses.
Topics: Animals; Chikungunya Fever; Chikungunya virus; Virus Replication; Viruses
PubMed: 30599050
DOI: 10.1007/82_2018_146 -
Frontiers in Immunology 2022Alphaviruses contain many human and animal pathogens, such as CHIKV, SINV, and VEEV. Accumulating evidence indicates that innate immunity plays an important role in... (Review)
Review
Alphaviruses contain many human and animal pathogens, such as CHIKV, SINV, and VEEV. Accumulating evidence indicates that innate immunity plays an important role in response to alphaviruses infection. In parallel, alphaviruses have evolved many strategies to evade host antiviral innate immunity. In the current review, we focus on the underlying mechanisms employed by alphaviruses to evade cGAS-STING, IFN, transcriptional host shutoff, translational host shutoff, and RNAi. Dissecting the detailed antiviral immune evasion mechanisms by alphaviruses will enhance our understanding of the pathogenesis of alphaviruses and may provide more effective strategies to control alphaviruses infection.
Topics: Alphavirus; Alphavirus Infections; Animals; Antiviral Agents; Humans; Immune Evasion; Nucleotidyltransferases
PubMed: 36172361
DOI: 10.3389/fimmu.2022.1005586 -
Biomedica : Revista Del Instituto... Jun 2021The chikungunya virus (CHIKV) is an Alphavirus that belongs to the Old World group. These arthritogenic viruses cause a febrile illness characterized by arthralgias and... (Review)
Review
The chikungunya virus (CHIKV) is an Alphavirus that belongs to the Old World group. These arthritogenic viruses cause a febrile illness characterized by arthralgias and myalgias. Although fatal cases during CHIKV infection are rare, the disease may be disabling and generate a broad spectrum of atypical manifestations, such as cardiovascular, respiratory, eye, kidney, and skin complications, among others. When joint pain persists for three or more months, it results in the chronic form of the disease called post-chikungunya chronic inflammatory rheumatism, which constitutes the main disease sequel. CHIKV is not considered a neurotropic virus; however, it can affect the central nervous system, especially in children and the elderly, causing severe and permanent sequelae. CHIKV outbreaks had been previously reported in Africa, Asia, and Europe, but the virus introduction to the American continent was documented until the end of 2013. Since then, the irus has spread to 45 countries and territories causing near two million cases in just two years. This review describes the molecular biology, clinical manifestations, pathogenesis, and significant post-infection complications of CHIKV. Additionally, it collects published information about the outbreak in Colombia and the American continent between 2014 and 2020.
Topics: Arthralgia; Chikungunya Fever; Chikungunya virus; Disease Outbreaks; Europe; Humans
PubMed: 34214275
DOI: 10.7705/biomedica.5797 -
The Journal of Clinical Investigation Jan 2023Alphaviruses are enveloped, insect-transmitted, positive-sense RNA viruses that infect humans and other animals and cause a range of clinical manifestations, including... (Review)
Review
Alphaviruses are enveloped, insect-transmitted, positive-sense RNA viruses that infect humans and other animals and cause a range of clinical manifestations, including arthritis, musculoskeletal disease, meningitis, encephalitis, and death. Over the past four years, aided by CRISPR/Cas9-based genetic screening approaches, intensive research efforts have focused on identifying entry receptors for alphaviruses to better understand the basis for cellular and species tropism. Herein, we review approaches to alphavirus receptor identification and how these were used for discovery. The identification of new receptors advances our understanding of viral pathogenesis, tropism, and evolution and is expected to contribute to the development of novel strategies for prevention and treatment of alphavirus infection.
Topics: Animals; Humans; Alphavirus Infections; Alphavirus
PubMed: 36647825
DOI: 10.1172/JCI165307 -
Nature Reviews. Microbiology Jun 2023Alphaviruses are arthropod-transmitted RNA viruses that cause epidemics of human infection and disease on a global scale. These viruses are classified as either... (Review)
Review
Alphaviruses are arthropod-transmitted RNA viruses that cause epidemics of human infection and disease on a global scale. These viruses are classified as either arthritogenic or encephalitic based on their genetic relatedness and the clinical syndromes they cause. Although there are currently no approved therapeutics or vaccines against alphaviruses, passive transfer of monoclonal antibodies confers protection in animal models. This Review highlights recent advances in our understanding of the host factors required for alphavirus entry, the mechanisms of action by which protective antibodies inhibit different steps in the alphavirus infection cycle and candidate alphavirus vaccines currently under clinical evaluation that focus on humoral immunity. A comprehensive understanding of alphavirus entry and antibody-mediated protection may inform the development of new classes of countermeasures for these emerging viruses.
Topics: Animals; Humans; Alphavirus; Alphavirus Infections; Antibodies, Monoclonal
PubMed: 36474012
DOI: 10.1038/s41579-022-00825-7 -
PLoS Pathogens Oct 2020Alphaviruses cause severe human illnesses including persistent arthritis and fatal encephalitis. As alphavirus entry into target cells is the first step in infection,... (Review)
Review
Alphaviruses cause severe human illnesses including persistent arthritis and fatal encephalitis. As alphavirus entry into target cells is the first step in infection, intensive research efforts have focused on elucidating aspects of this pathway, including attachment, internalization, and fusion. Herein, we review recent developments in the molecular understanding of alphavirus entry both in vitro and in vivo and how these advances might enable the design of therapeutics targeting this critical step in the alphavirus life cycle.
Topics: Alphavirus; Alphavirus Infections; Animals; Host-Pathogen Interactions; Humans; Virus Internalization; Virus Replication
PubMed: 33091085
DOI: 10.1371/journal.ppat.1008876 -
Viruses Aug 2023Mayaro virus (MAYV), the etiologic agent of Mayaro fever, leads patients to severe myalgia and arthralgia, which can have a major impact on public health in all the... (Review)
Review
Mayaro virus (MAYV), the etiologic agent of Mayaro fever, leads patients to severe myalgia and arthralgia, which can have a major impact on public health in all the countries where the virus circulates. The emergence and dissemination of new viruses have led the scientific community to develop new in vivo models that can help in the fight against new diseases. So far, mice have been the most used animal model in studies with MAYV and have proved to be an adequate model for recapitulating several aspects of the disease observed in humans. Mice are widely used in in vivo research and, therefore, are well known in the scientific community, which has allowed for different strains to be investigated in the study of MAYV. In this review, we summarize the main studies with MAYV using mice as an experimental model and discuss how they can contribute to the advancement of the understanding of its pathogenesis and the development of new drugs and vaccines.
Topics: Humans; Animals; Mice; Alphavirus Infections; Alphavirus; Disease Models, Animal
PubMed: 37766210
DOI: 10.3390/v15091803 -
Viruses Aug 2019Alphaviruses belong to a family of positive sense, single-stranded RNA viruses that are transmitted mainly by mosquitoes through a blood meal and cause arthritis and/or...
Alphaviruses belong to a family of positive sense, single-stranded RNA viruses that are transmitted mainly by mosquitoes through a blood meal and cause arthritis and/or encephalitis in humans and animals [...].
Topics: Animals; Arthritis; Chikungunya Fever; Chikungunya virus; Communicable Diseases, Emerging; Disease Outbreaks; Encephalitis; Humans; Mosquito Vectors
PubMed: 31450552
DOI: 10.3390/v11090779