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Clinical Microbiology Reviews Jul 2016Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947... (Review)
Review
Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947 and from mosquitoes in 1948 in Africa, and ZIKV infections in humans were sporadic for half a century before emerging in the Pacific and the Americas. ZIKV is usually transmitted by the bite of infected mosquitoes. The clinical presentation of Zika fever is nonspecific and can be misdiagnosed as other infectious diseases, especially those due to arboviruses such as dengue and chikungunya. ZIKV infection was associated with only mild illness prior to the large French Polynesian outbreak in 2013 and 2014, when severe neurological complications were reported, and the emergence in Brazil of a dramatic increase in severe congenital malformations (microcephaly) suspected to be associated with ZIKV. Laboratory diagnosis of Zika fever relies on virus isolation or detection of ZIKV-specific RNA. Serological diagnosis is complicated by cross-reactivity among members of the Flavivirus genus. The adaptation of ZIKV to an urban cycle involving humans and domestic mosquito vectors in tropical areas where dengue is endemic suggests that the incidence of ZIKV infections may be underestimated. There is a high potential for ZIKV emergence in urban centers in the tropics that are infested with competent mosquito vectors such as Aedes aegypti and Aedes albopictus.
Topics: Animals; Disease Outbreaks; Early Diagnosis; Humans; Insect Vectors; Phylogeny; Urban Renewal; Zika Virus; Zika Virus Infection
PubMed: 27029595
DOI: 10.1128/CMR.00072-15 -
Virulence Dec 2021The Flavivirus genus consists of >70 members including several that are considered significant human pathogens. Flaviviruses display a broad spectrum of diseases that... (Review)
Review
The Flavivirus genus consists of >70 members including several that are considered significant human pathogens. Flaviviruses display a broad spectrum of diseases that can be roughly categorised into two phenotypes - systemic disease involving haemorrhage exemplified by dengue and yellow Fever virus, and neurological complications associated with the likes of West Nile and Zika viruses. Attempts to develop vaccines have been variably successful against some. Besides, mosquito-borne flaviviruses can be vertically transmitted in the arthropods, enabling long term persistence and the possibility of re-emergence. Therefore, developing strategies to combat disease is imperative even if vaccines become available. The cellular interactions of flaviviruses with their human hosts are key to establishing the viral lifecycle on the one hand, and activation of host immunity on the other. The latter should ideally eradicate infection, but often leads to immunopathological and neurological consequences. In this review, we use Dengue and Zika viruses to discuss what we have learned about the cellular and molecular determinants of the viral lifecycle and the accompanying immunopathology, while highlighting current knowledge gaps which need to be addressed in future studies.
Topics: Animals; Dengue; Dengue Virus; Flavivirus; Flavivirus Infections; Virulence; Zika Virus; Zika Virus Infection
PubMed: 34696709
DOI: 10.1080/21505594.2021.1996059 -
Virus Genes Dec 2022Bovine viral diarrhea virus (BVDV) belongs to the family Flaviviridae genus pestivirus. The viral genome is a single-stranded, positive-sense RNA that encodes four... (Review)
Review
Bovine viral diarrhea virus (BVDV) belongs to the family Flaviviridae genus pestivirus. The viral genome is a single-stranded, positive-sense RNA that encodes four structural proteins (i.e., C, Erns, E1, and E2) and eight non-structural proteins (NSPs) (i.e., Npro, p7, NS2, NS3, NS4A, NS4B, NS5A, and NS5B). Cattle infected with BVDV exhibit a number of different clinical signs including diarrhea, abortion, and other reproductive disorders which have a serious impact on the cattle industry worldwide. Research on BVDV mainly focuses on its structural protein, however, progress in understanding the functions of the NSPs of BVDV has also been made in recent decades. The knowledge gained on the BVDV non-structural proteins is helpful to more fully understand the viral replication process and the molecular mechanism of viral persistent infection. This review focuses on the functions of BVDV NSPs and provides references for the identification of BVDV, the diagnosis and prevention of Bovine viral diarrhea mucosal disease (BVD-MD), and the development of vaccines.
Topics: Animals; Cattle; Viral Nonstructural Proteins; RNA, Viral; Cell Line; Diarrhea Viruses, Bovine Viral; Bovine Virus Diarrhea-Mucosal Disease; Diarrhea; Diarrhea Virus 1, Bovine Viral
PubMed: 35614328
DOI: 10.1007/s11262-022-01914-8 -
Virologica Sinica Feb 2017Dengue virus (DENV) is a mosquito-borne virus belonging to the Flaviviridae family. There are 4 serotypes of DENV that cause human disease through transmission by... (Review)
Review
Dengue virus (DENV) is a mosquito-borne virus belonging to the Flaviviridae family. There are 4 serotypes of DENV that cause human disease through transmission by mosquito vectors. DENV infection results in a broad spectrum of clinical symptoms, ranging from mild fever to dengue hemorrhagic fever (DHF), the latter of which can progress to dengue shock syndrome (DSS) and death. Researchers have made unremitting efforts over the last half-century to understand DHF pathogenesis. DHF is probably caused by multiple factors, such as virus-specific antibodies, viral antigens and host immune responses. This review summarizes the current progress of studies on DHF pathogenesis, which may provide important information for achieving effective control of dengue in the future.
Topics: Antibodies, Blocking; Antibodies, Viral; Dengue Virus; Host-Pathogen Interactions; Humans; Severe Dengue
PubMed: 27853992
DOI: 10.1007/s12250-016-3855-9 -
Molecular Cell Feb 2020The RNA modification N-methyladenosine (mA) modulates mRNA fate and thus affects many biological processes. We analyzed mA across the transcriptome following infection...
The RNA modification N-methyladenosine (mA) modulates mRNA fate and thus affects many biological processes. We analyzed mA across the transcriptome following infection by dengue virus (DENV), Zika virus (ZIKV), West Nile virus (WNV), and hepatitis C virus (HCV). We found that infection by these viruses in the Flaviviridae family alters mA modification of specific cellular transcripts, including RIOK3 and CIRBP. During viral infection, the addition of mA to RIOK3 promotes its translation, while loss of mA in CIRBP promotes alternative splicing. Importantly, viral activation of innate immune sensing or the endoplasmic reticulum (ER) stress response contributes to the changes in mA in RIOK3 or CIRBP, respectively. Further, several transcripts with infection-altered mA profiles, including RIOK3 and CIRBP, encode proteins that influence DENV, ZIKV, and HCV infection. Overall, this work reveals that cellular signaling pathways activated during viral infection lead to alterations in mA modification of host mRNAs to regulate infection.
Topics: Adenosine; Cell Line; Dengue; Dengue Virus; Flaviviridae; Flaviviridae Infections; Hepacivirus; Hepatitis C; Host-Pathogen Interactions; Humans; Protein Serine-Threonine Kinases; RNA, Messenger; RNA-Binding Proteins; Virus Replication; Zika Virus; Zika Virus Infection
PubMed: 31810760
DOI: 10.1016/j.molcel.2019.11.007 -
Current Biology : CB Dec 2016What do Zika, Dengue and West Nile viruses have in common? All are members of a family of viruses called the Flaviviruses. Here, Sonja Best lays out the essentials of...
What do Zika, Dengue and West Nile viruses have in common? All are members of a family of viruses called the Flaviviruses. Here, Sonja Best lays out the essentials of this group of significant human pathogens.
Topics: Animals; Flaviviridae Infections; Flavivirus; Gene Expression Regulation, Viral; Genome, Viral; Humans; RNA, Viral; Viral Proteins
PubMed: 27997831
DOI: 10.1016/j.cub.2016.09.029 -
Uirusu Dec 2011Family Flaviviridae genus flavivirus contains numerous pathogenic viruses such as Japanese encephalitis virus, dengue virus, West Nile virus, etc, which cause public... (Review)
Review
Family Flaviviridae genus flavivirus contains numerous pathogenic viruses such as Japanese encephalitis virus, dengue virus, West Nile virus, etc, which cause public health problems in the world. Since many mammals and birds can act as amplifying hosts and reservoir hosts in nature and those viruses are transmitted by haematophagous mosquitoes or ticks, those viruses could not be eradicated from the nature. In the recent few decades, the viral replication mechanism and the ultrastructure of viral proteins as well as the viral immune evasion mechanism have been elucidated extensively, leading to develop novel types of antivirals and vaccines. In this review, the flavivirus nature and epidemiology, replication mechanism, immune response and immune evasion, and antivirals and vaccines against flaviviruses were described.
Topics: Animals; Flavivirus; Flavivirus Infections; Humans; Immune Evasion; Viral Vaccines; Virus Replication
PubMed: 22916569
DOI: 10.2222/jsv.61.221 -
Oxidative Medicine and Cellular... 2019Oxidative stress is induced once the balance of generation and neutralization of reactive oxygen species (ROS) is broken in the cell, and it plays crucial roles in a... (Review)
Review
Oxidative stress is induced once the balance of generation and neutralization of reactive oxygen species (ROS) is broken in the cell, and it plays crucial roles in a variety of natural and diseased processes. Infections of viruses trigger oxidative stress, which affects both the cellular metabolism and the life cycle of the viruses. Oxidative stress associated with specific viral proteins, experimental culture systems, and patient infections, as well as its correlations with the viral pathogenesis attracts much research attention. In this review, we primarily focus on hepatitis C virus (HCV), dengue virus (DENV), Zika virus (ZIKV), Japanese encephalitis virus (JEV), West Nile virus (WNV), and tick-borne encephalitis virus (TBEV) as representatives of viruses and we summarize the mechanisms involved in the relevance of oxidative stress for virus-associated pathogenesis. We discuss the current understanding of the pathogenic mechanisms of oxidative stress induced by viruses and highlight the relevance of autophagy and DNA damage in the life cycle of viruses. Understanding the crosstalk between viral infection and oxidative stress-induced molecular events may offer new avenues for antiviral therapeutics.
Topics: Animals; DNA Damage; Flaviviridae; Flaviviridae Infections; Humans; Oxidative Stress
PubMed: 31531178
DOI: 10.1155/2019/1409582 -
Frontiers in Cellular and Infection... 2022The Flaviviridae are a family of positive-sense, single-stranded RNA enveloped viruses, and their members belong to a single genus, Flavivirus. Flaviviruses are found in... (Review)
Review
The Flaviviridae are a family of positive-sense, single-stranded RNA enveloped viruses, and their members belong to a single genus, Flavivirus. Flaviviruses are found in mosquitoes and ticks; they are etiological agents of: dengue fever, Japanese encephalitis, West Nile virus infection, Zika virus infection, tick-borne encephalitis, and yellow fever, among others. Only a few flavivirus vaccines have been licensed for use in humans: yellow fever, dengue fever, Japanese encephalitis, tick-borne encephalitis, and Kyasanur forest disease. However, improvement is necessary in vaccination strategies and in understanding of the immunological mechanisms involved either in the infection or after vaccination. This is especially important in dengue, due to the immunological complexity of its four serotypes, cross-reactive responses, antibody-dependent enhancement, and immunological interference. In this context, mucosal vaccines represent a promising alternative against flaviviruses. Mucosal vaccination has several advantages, as inducing long-term protective immunity in both mucosal and parenteral tissues. It constitutes a friendly route of antigen administration because it is needle-free and allows for a variety of antigen delivery systems. This has promoted the development of several ways to stimulate immunity through the direct administration of antigens (e.g., inactivated virus, attenuated virus, subunits, and DNA), non-replicating vectors (e.g., nanoparticles, liposomes, bacterial ghosts, and defective-replication viral vectors), and replicating vectors (e.g., , , , and viral vectors). Because of these characteristics, mucosal vaccination has been explored for immunoprophylaxis against pathogens that enter the host through mucosae or parenteral areas. It is suitable against flaviviruses because this type of immunization can stimulate the parenteral responses required after bites from flavivirus-infected insects. This review focuses on the advantages of mucosal vaccine candidates against the most relevant flaviviruses in either humans or animals, providing supporting data on the feasibility of this administration route for future clinical trials.
Topics: Animals; Encephalitis, Japanese; Encephalitis, Tick-Borne; Flavivirus; Mosquito Vectors; Vaccination; West Nile Fever; Yellow Fever; Zika Virus; Zika Virus Infection
PubMed: 35782117
DOI: 10.3389/fcimb.2022.887729 -
Uirusu Dec 2011Members of the genus Pestivirus, are causative agents of economically important diseases for livestock and wild animals that occur worldwide, such as bovine viral... (Review)
Review
Members of the genus Pestivirus, are causative agents of economically important diseases for livestock and wild animals that occur worldwide, such as bovine viral diarrhea, classical swine fever, and border disease of sheep. Pestivirus have novel insertions of host genes in the viral genome and functions of unique viral proteins, N(pro) and E(rns), related to the pathogenicity although genomic structure is closely related to the other viruses of Flaviviridae family, especially hepatitis C virus. In this review, recent studies on the molecular basis of pathogenicity of pestivirus infections were summarized.
Topics: Animals; Cattle; Genome, Viral; Humans; Pestivirus; Pestivirus Infections; Phylogeny; Viral Proteins
PubMed: 22916570
DOI: 10.2222/jsv.61.229