Flavivirus - Science topic

Dengue virus (DENV) serotypes 1–4 are mosquito‐borne flaviviruses that are responsible for significant morbidity and mortality worldwide, particularly in tropical and subtropical regions. Although two vaccines have been approved, their unbalanced efficacy across serotypes poses potential risks for specific populations. There are currently no approv...

γδ T cells are a unique subset of unconventional T cells and an important component of the innate immune system. Unlike conventional αβ T cells, γδ T cells can respond rapidly during the early stages of infection, and their antigen recognition is not restricted by MHC molecules. These distinctive features underscore the important role of γδ T cells...

Autoimmune encephalitis due to antibodies directed to the cell surface of N-methyl-D-aspartate receptor (NMDAR) can cause a range of symptoms, from psychiatric abnormalities to impairment of cognition and movement disorder, such as choreoathetosis. The disease was first described in 2007 in patients with ovarian teratoma. Since then, there have bee...

The Alongshan virus (ALSV), classified within the Flaviviridae family and belonging to the Jingmenvirus group, is a segmented RNA virus that was first identified in China in 2017. Since then, it has been reported in several Eurasian countries. Although no confirmed fatal cases have been documented, the potential public health risks associated with...

Small extracellular vesicles (sEVs), also known as exosomes, are membranous vesicles filled with various proteins and nucleic acids, serving as a communication vector between cells. Recent research has highlighted their role in viral diseases. This review synthesizes current understanding of viral sEVs and includes recent findings on sEVs infected...

Background Mosquitoes transmit various pathogens causing diseases like Zika, Dengue, West Nile and Chikungunya. They also harbour insect‐specific viruses (ISVs) and Wolbachia, which can block arbovirus transmission. This study investigated the prevalence of Orthoflavivirus and Wolbachia in mosquito populations from three provinces in Türkiye. Meth...

Dengue fever is a widespread viral infection endemic in tropical and subtropical regions. While its common manifestations include fever, headache, and musculoskeletal pain, gastrointestinal complications such as colonic perforation are exceedingly rare. Dengue is a viral disease with reported incidence of upto 96 million cases worldwide. Dengue is...

Dengue virus (DENV) and West Nile (WNV) viruses are important re-emerging mosquito-borne members of the genus Flavivirus that are under-recognized in many parts of Africa. This review aims to evaluate the existing literature on the transmission, epidemiology, diagnostic techniques, clinical presentation and prevention of infection with DENV and WNV...

Purpose of Review This review explores the critical interactions between Zika virus (ZIKV) and human cell receptors, focusing on their roles in viral entry, pathogenesis, and potential therapeutic interventions. Recent Findings Recent studies have identified several key receptors involved in ZIKV infection, including phosphatidylserine receptors (...

Background Culex theileri (Theobald, 1903) is distributed in Afrotropical, Paleartic, and Oriental regions. It is a mainly mammophilic floodwater mosquito that is involved in the transmission of West Nile virus (WNV, renamed as Orthoflavivirus nilense by the International Committee on Taxonomy of Viruses [ICTV]) in Africa. This virus is a mosquito-...

Background Zika virus (ZIKV) is an emerging flavivirus that may cause innate microcephaly or neurological disturbances. Yet no antiviral has been approved by FDA against ZIKV infection. It was shown that some unsaturated fatty acids could inactivate enveloped viruses including SARS-CoV-2. However, studies investigating the effect of eicosapentaenoi...

Insect-borne viruses may account for a significant proportion of non-malaria and non-bacterial febrile illnesses in Liberia. Although the presence of many arthropod vectors has been documented, the collective burden of arbovirus infections and baseline pre-existing immunity remains enigmatic. Our goal was to determine the seroprevalence of arboviru...

Introduction The flavivirus infections caused by the Zika virus (ZIKV), Dengue virus (DENV), and West Nile virus (WNV) cause mild to serious pathological conditions, such as fever, joint pain, shock, internal bleeding, organ failure, nausea, breathlessness, brain tissue damage, neurodegenerative diseases, and deaths. As currently no efficient vacci...

Background Dengue fever remains a significant public health challenge in Bangladesh. This study aimed to characterize the clinical and epidemiological profiles of confirmed dengue cases during the 2024 outbreak in Bangladesh. Methods This observational study was conducted from June to September 2024 in four tertiary care hospitals across Banglades...

West Nile virus (WNV) is a mosquito-borne flavivirus mainly circulating in eastern Germany, causing annually reoccurring epizootics in the avifauna as well as sporadic infections in humans and horses. WNV is closely-related to Usutu virus (USUV) and tick-borne encephalitis virus (TBEV) and co-infections thereof are becoming more frequent. To not so...

Background Tick-borne encephalitis virus (TBEV) is expanding its range in Europe, with increasing human cases reported. Since the first detection of TBEV in ticks in the United Kingdom in 2019, one possible, two probable and two confirmed autochthonous cases in humans have been reported. Aim We aimed to understand the environmental and ecological...

West Africa serves as a critical region for the co‐circulation of mosquito‐borne flaviviruses, which often precipitate sporadic outbreaks. This study investigated the seropositivity to dengue virus serotypes 1–4 (DENV‐1–4), Zika virus (ZIKV), yellow fever virus (YFV), and West Nile virus (WNV) in three regions of Senegal: Sindia, Thies, and Kedougo...

Flavivirus infections by Dengue and Zika virus impose a significant healthcare threat worldwide. At present no FDA-approved specific antiviral treatment is available, and the safety of a vaccine against Dengue virus is still under debate. Here, we report the identification of the CADA derivative flavitransin (FT), with potent activity against DENV...

ABSTARCT Objective: The tick-borne encephalitis virus (TBEV), a flavivirus transmitted by Ixodes spp. ticks, can cause a clinical picture characterized by nonspecific symptoms, as well as more specific conditions such as encephalitis and myelitis. Most patients admitted and followed with a preliminary diagnosis of Crimean-Congo hemorrhagic fever (C...

Long-term serologic surveillance of red-legged partridges suggests emergence of Bagaza virus in Portugal in 2021, associated with disease outbreaks in this species. Results also reveal sporadic circulation of Usutu virus and endemic circulation of West Nile virus, highlighting the role of red-legged partridges in the transmission and maintenance cy...

Following the first outbreak of Murray Valley encephalitis in Victoria, Australia, since 1974, a serological survey was conducted in 2023 and 2024 to estimate the seroprevalence of Murray Valley encephalitis virus (MVEV) antibodies among residents in the north of the state. Between October 2023 and April 2024, a total of 507 residents from 11 local...

Understanding flavivirus immunity is critical for the development of pan-flavivirus vaccines. Dendritic cells (DC) coordinate antiviral innate and adaptive immune responses, and they can be targeted by flaviviruses as a mechanism of immune evasion. Using an unbiased genome-wide approach designed to specifically identify flavivirus-modulated pathway...

Wolbachia pipientis is an intracellular endosymbiotic bacterium that blocks the replication of several arboviruses in transinfected Aedes aegypti mosquitoes, yet its antiviral mechanism remains unknown. For the first time, we employed Nanopore direct RNA sequencing technology to investigate the impact of wAlbB strain of Wolbachia on the host’s N⁶-m...

Live and wet markets (LWMs) form an important pillar of food supply in Asian countries, but the close interaction of animals and humans at markets creates an interface for disease transmission. The zoonotic risks associated with LWMs were highlighted after the onset of the COVID-19 pandemic. This study aimed to investigate the risk for mosquito-bor...

Interspecies transmission of viruses poses significant risks to animal and human health. Tembusu virus (TMUV), an emerging flavivirus, is primarily associated with avian diseases. This study reports the first documented natural infection of TMUV in mammals, specifically zoo dolphins in Thailand, offering insights into its evolution, transmission dy...

Dengue virus (DENV) is the causative agent of dengue fever and exerts a substantial healthcare burden worldwide. Like other flaviviruses, DENV must undergo membrane fusion with the host cell in order to initiate infection. This membrane fusion occurs following acidification during endocytosis and is pH dependent. Here, we interrogate whether the me...

West Nile virus (WNV) and Usutu virus (USUV) are closely related mosquito-borne neurotropic flaviviruses that share common transmission cycle and can infect humans. However, while human infections by WNV are widespread, infections by USUV are comparatively less frequent, less severe, and currently limited to Africa and Europe. To identify human hos...

A hallmark of the dengue virus (DENV) infection is the manipulation of host cell membranes, lipid trafficking and lipid droplets (LDs), all cellular functions that depend on the cytoskeleton and the cytoplasmatic streaming system. We previously reported the interaction between DENV NS1 protein and members of the kinesin motor complex in the Aedes a...

Background: Dengue is a viral disease transmitted by mosquitoes that has rapidly spread across various regions, with its global incidence rising significantly in recent decades. Currently, nearly half of the world’s population is at risk. The dengue virus (DENV), mainly transmitted by Aedes mosquitoes, especially Aedes aegypti, can cause symptoms r...

The Exon Junction Complex (EJC) deposited upstream of exon-exon junctions during pre-mRNA splicing in the nucleus remains stably bound to RNA to modulate mRNA fate at multiple post-transcriptional steps until its disassembly during translation. Here, we investigated two EJC disassembly mechanisms in human embryonic kidney 293 (HEK293) cells, one me...

Zika virus is gradually emerging and leading to an alarming concern all over the world in recent times. Zika virus is considered as positive strand single stranded RNA virus belonging to the genus Flavivirus in the Flaviviridae family. The non-segmented virus possesses an icosahedral shape with a virion of size ranging from 40-60nm in diameter wher...

Dengue is a vector-borne viral disease caused by the flavivirus dengue virus (DENV) that continue to circulate worldwide. A positive-stranded enveloped RNA virus (DENV) is principally transmitted by Aedes mosquitoes. It has four antigenically distinct serotypes, DENV-1 to DENV-4. This review highlights pathophysiology and clinical signs of Dengue V...

Dengue fever is a mosquito-borne flavivirus infection, and its clinical presentation varies from febrile illness and hemorrhagic manifestations such as petechiae and mucosal bleeding to life-threatening complications such as dengue shock syndrome. Ocular findings in dengue fever have a wide spectrum of manifestations ranging from mild non-specific...

Statins are among the most frequently prescribed medications. In addition to their well-established effectiveness in lowering total cholesterol, LDL, and triglycerides, statins have been described to have immunomodulatory and anti-inflammatory properties and have been associated with improved endothelial functions. Given the common use of statins,...

Zika virus (ZIKV) is spread by mosquito bites and is unique among known flaviviruses for being able to cause microcephaly. Entry factors for ZIKV are incompletely understood, but phosphatidylserine (PS) receptors, including the TAM (Tyro3, AXL, and Mer) and TIM (T-cell Ig mucin) families, can serve as cofactors for flavivirus entry in a cell type-s...

In the history of yellow fever (YF) outbreaks in Brazil, howler monkeys (Alouatta sp.) and marmosets (Callithrix sp.) have been among the most affected genera, exhibiting significant hepatic injuries similar to those seen in humans. However, limited information exists regarding yellow fever virus (YFV) infection in their central nervous system (CNS...

Background Mosquitoes are efficient vectors of medically significant flaviviruses and serve as hosts for insect-specific flaviviruses (ISFs). Aedes flavivirus (AEFV) is a classical ISF. Given the increasing discovery of ISFs, it is urgent to evaluate the potential risk of ISFs to human health as well as their impact on the transmission of pathogeni...

Mosquito-borne flaviviruses, including dengue (DENV) and Zika (ZIKV) viruses, have caused widespread epidemics in areas with high HIV prevalence, partly due to the expanded geographic range of arthropod vectors. Despite the occurrence of large flavivirus outbreaks in areas with high HIV prevalence, little is known about the effects of flavivirus in...

Birds are natural hosts for numerous zoonotic viral pathogens, including West Nile virus, which is transmitted by mosquitoes. During migration, birds can act as vectors for the geographic spread of viruses. WNV is endemic in Portugal, causing annual outbreaks, particularly in horses. Here, we report the first detection of an avian WNV strain isolat...

Yellow fever (YF) is a viral hemorrhagic disease transmitted primarily by Haemagogus species in sylvatic areas and by Aedes species in urban areas [1]. It is endemic in tropical regions of Africa and South America, including Colombia [2]. It causes asymptomatic infection, fever, jaundice, and even severe organ failure, with a high case fatality rat...

Autochthonous dengue cases have been continuously recorded in Europe in the past two decades. The first autochthonous dengue case in Croatia was reported in 2010 on the Pelješac Peninsula, while imported cases were recorded continuously thereafter. In 2024, dengue re-emerged in Croatia. An epidemiological and entomological study was conducted after...

Zika virus (ZIKV) is a mosquito-borne flavivirus of the family Flaviviridae. The association between ZIKV and microcephaly was first described in Brazil in 2015. The risk of vertical transmission occurs in pregnant women with or without symptoms, and the risk of malformation appears to be worse when infection occurs in the first and second trimeste...

Dengue virus (DENV) is spread through bites from mosquitos of the Aedes genus. DENV activates antibodies against 4 dengue serotypes, which are identified by the plaque reduction neutralization test of 50%, and the dengue antivirals use nonstructural viral antigens to excite T cells. Dengue vaccines include a live attenuated vaccine, inactivated vac...

Introduction and importance Acute flaccid paralysis is a rare neurological complication of Japanese Encephalitis infection, which may involve one or multiple limbs. Symmetric involvement of upper and lower limbs such as in this case is rarely reported. Presentation of case We present a case of a 30-year young male from terai region of Nepal who pr...

Background Flavivirus infections pose a significant global health burden, highlighting the need for safe and effective vaccination strategies. Co-administration of different vaccines, including licensed flavivirus vaccines, is commonly practiced providing protection against multiple pathogens while also saving time and reducing visits to healthcare...

Zika virus (ZIKV) caused unprecedented outbreaks in South America and the Caribbean in 2015–2016, leading primarily to a series of abnormalities in neonates termed congenital Zika syndrome. The threat of ZIKV reemergence has seen the development of multiple ZIKV vaccines that are at the preclinical stage or in early-stage clinical trials. Herein, w...

The complex immune interactions produced by the tetravalent dengue vaccine Dengvaxia have foregrounded the important role of antibody-dependent enhancement (ADE) in dengue infection. Some evidence exists that ADE may extend beyond the four dengue serotypes to Zika, a closely related flavivirus transmitted by the same mosquito species as dengue, and...

ZIKA fever (ZIKAF) is an emerging mosquito-borne flavivirus illness in humans. Regarding the etiological agent, ZIKA virus (ZIKAV), though it is known to be distributed in the tropics, causing sporadic cases, its rapid global expansion with pandemic potential has raised global concern. Due to its abrupt emergence in South American countries, the Ca...

Introduction The Zika virus is an emerging Flavivirus known to cause Zika infection in humans. It is associated with severe health problems such as microcephaly and Guillain-Barré syndrome post the Brazilian epidemic in 2015-16. The spread of the Zika virus to the Asian subcontinent, especially to India is a matter of great concern. Two recent co-c...

Zika virus (ZIKV) is a member of the Flaviviridae family and causes congenital microcephaly and Guillain–Barré syndrome. Currently, there is a lack of approved vaccines or therapies against ZIKV infection. In this study, we profile vRNA‒host protein interactomes at ZIKV stem‒loop B (SLB) and reveal that interleukin enhancer binding factor 3 (ILF3)...

Powassan virus (POWV) is an emergent tick-borne flavivirus that causes lethal encephalitic disease and chronic neurologic deficits in surviving patients. POWV-LI9 is a tick-derived isolate that causes neurovirulent disease and age-dependent lethality in mice. Serial passage of VeroE6 cells infected with LI9 resulted in eight amino acid changes in a...

Background. West Nile virus (WNV) is a zoonotic mosquito-borne Flavivirus, with bird populations reservoirs. Although often asymptomatic, infection in humans can cause febrile symptoms and more rarely, severe neurological symptoms that may lead to death. Mapping WNV bird reservoir is important towards understanding the distribution of WNV cases in...

Omsk hemorrhagic fever virus (OHFV) is a tick-borne flavivirus associated with acute febrile illness and hemorrhagic disease in humans. OHFV was first identified in 1947 and since its identification has largely remained endemic to the Omsk region of the Russian Federation, where it continues to result in illnesses each year. However, the 2 primary...

Flaviviruses are the causative agents of viral hemorrhagic fever (VHF) globally and have demonstrated the capacity to result in fatal outcomes if not managed effectively. Among different types of flaviviruses, dengue (DENV) and Japanese encephalitis (JEV) viruses are the most common in tropical and subtropical countries. While vaccines have been de...

West Nile Virus (VNV) produces encephalitic West Nile Fever (WNF), a zoonotic disease that can affect birds, is a viral disease that can infect horses as well as other mammals, birds and humans as a result of infection by arbovirus-Orthoflavivirus nilense, from family Flaviviridae. Cases of dead affected wild birds during the summer season have bee...

Japanese encephalitis (JE) is a severe disease caused by the Japanese encephalitis virus of the genus Flavivirus and the family Flaviviridae. Mosquitoes of the Culex Vishnu subgroup, particularly Culex tritaeniorhynchus, are the main vectors of JEV. This zoophilic mosquito species is sustained in an enzootic cycle with pigs and wading birds as ampl...

Tick-borne encephalitis virus (TBEV) is an emerging pathogen that initially causes flu-like symptoms and can progress to central nervous system (CNS) infections. Tick-borne encephalitis (TBE) is an endemic disease in southern coastal counties with regular human cases, while the causative agent, TBEV, is prevalent in ticks in most of the coastal reg...

Background. Flaviviruses spread from endemic to non-endemic areas, causing illness in millions of people worldwide. The lack of effective therapies and the rapid expansion of flaviviral infections worldwide emphasize the importance of finding effective antivirals to treat such diseases. Objectives. To find out the potential broad-spectrum flaviviru...

AT-9010 (2'-methyl-2'-fluoro guanosine triphosphate) is a GTP analog whose prodrug, AT-752 is under consideration in human medicine as a potential antiviral drug against certain flaviviruses. It was previously believed to inhibit viral replication by acting primarily as a chain terminator. However, it was discovered recently that it also binds the...

Arboviruses represent a global public health challenge. The lack of diagnostic protocols and the presence of asymptomatic infections complicate confirmatory diagnostics. Alphaviruses, such as the equine encephalitis viruses, can cause severe outbreaks and are usually misdiagnosed as dengue. Thus, evidence for their circulation was assessed here. Pl...

Post-translational modifications (PTMs) serve as critical regulators of protein function across biological systems, including during viral infection. For orthoflaviviruses, including human pathogens like dengue, Zika, and West Nile viruses, PTMs on viral proteins regulate multiple aspects of the viral lifecycle and pathogenesis. Here, we review the...

Introduction The mosquito‐transmitted Usutu virus has spread in the last few years, becoming endemic in several areas of Europe, such as in the southern French region of the Camargue. Our aim was to study the relationships between the presence of the viral agent in Culex mosquitoes and the structure of bird communities in the context of the dilutio...

The growing importance of the Usutu virus (USUV) as an emerging zoonotic viral pathogen motivated Poland to investigate the epidemiological status of USUV infections among native bird species. Consequently, out of the 357 birds tested, 34 avian individuals from different geographical areas of the country were confirmed to be USUV-positive by RT-PCR...

Purpose of Review Japanese encephalitis (JE) is a viral disease transmitted by vectors and is prevalent in parts of Asia and the Pacific. In Nepal, it has been a major public health concern since 1978, especially in the Terai region, a lowland area along the border with India. Recent Findings Several factors contribute to the emergence and re-emer...

Dengue, a vector-borne acute febrile illness caused by members of the Flavivirus genus, has dramatically increased its occurrence worldwide. Neurological complications of dengue range from 2.63 to 40%, and subarachnoid hemorrhage is a rare, but significant manifestation. Hemophagocytic lymphohistiocytosis is a life-threatening hyperinflammatory syn...

El dengue es una enfermedad infecciosa ocasionada por un flavivirus, denominado virus del dengue (DENV), del cual se conocen cuatro serotipos distintos (DENV1, DENV2, DENV3 y DENV4). Esta enfermedad representa una amenaza a la salud pública global y se estima que ocurren 390 millones de infecciones anualmente. En las Américas, el dengue es la arbov...

Omsk hemorrhagic fever virus (OHFV) is the etiological agent of a poorly studied acute viral disease, causing several epidemic waves observed in the western Siberia regions of Omsk, Kurgan, Novosibirsk, and Tyumen. OHFV is a flavivirus and shares structural and morphological features with tick-borne encephalitis (TBE) complex viruses. The disease’s...

Zika, a mosquito-borne flavivirus, has been found in 87 countries and territories. Global outbreaks peaked in 2016. Prenatal infection of Zika virus was found to be associated with microcephaly, arthrogryposis, intracranial calcifications, fetal growth restriction, and fetal demise. The most severely affected children were diagnosed with congenital...

Background/Objective: World Health Organization latest statistics state that 17% of infectious diseases are transmitted by vectors, causing more than 700,000 deaths each year. Particularly, dengue (DENV), Zika (ZIKV) and yellow fever (YFV) viral infections have generated international awareness due to their epidemic proportion and risks of internat...

Background Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is an autoimmune condition that is increasingly being recognized as a complication of central nervous system infections. While association with herpes simplex virus encephalitis is well established, the condition has also been reported to occur following Japanese encephalitis virus i...

Orthoflavivirus, a genus encompassing arthropod-borne, positive-sense, single-stranded RNA viruses in the Flaviviridae family, represents clinically relevant viruses that pose significant threats to human and animal health worldwide. With warming climates and persistent urbanization, arthropod vectors and the viruses they transmit continue to widen...

Biomolecules continually sample alternative conformations. Consequently, even the most energetically favored ground conformational state has a finite lifetime. Here, we show that, in addition to the three-dimensional (3D) structure, the lifetime of a ground conformational state determines its biological activity. Using hydrogen–deuterium exchange n...

Zika virus (ZIKV) is a flavivirus transmitted primarily by the bite of infected Aedes species mosquitoes. Although typically asymptomatic or causing mild symptoms and infrequent neurological disease in older children and adults, infection during pregnancy can result in severe congenital malformations and neurodevelopmental deficits. We conducted a...

The pathogenesis of the central nervous system (CNS) pathology in tick-borne encephalitis (TBE) remains unclear. We attempted to identify mediators of the blood–brain barrier (BBB) disruption in human TBE in paired serum and cerebrospinal fluid (CSF) samples from 100 TBE patients. CSF albumin quotient (Qalb) was calculated as a measure of BBB impai...

A dengue, uma doença febril aguda causada pelo vírus da família Flaviviridae e gênero Flavivirus, transmitida pelo mosquito Aedes aegypti, representa um grave problema de saúde pública, especialmente no Brasil. Este estudo teve como objetivo analisar o perfil epidemiológico dos casos confirmados de dengue em um município do estado do Paraná, abrang...

Arboviruses pose significant public health challenges globally, particularly in Pakistan, where deforestation, climate change, urbanization, inadequate sanitation, and natural disasters have all contributed to the spread of mosquito-borne flavivirus diseases like dengue fever. The lack of a thorough national surveillance system has made it difficul...

Flaviviruses, such as dengue virus (DENV), Zika virus (ZIKV), West Nile virus (WNV), Japanese encephalitis virus (JEV), and yellow fever virus (YFV), constitute a significant public health concern with billions of people at risk of infection. Climate change and the expanding geographical distribution of mosquito vectors transmitting flaviviruses ha...

Dengue Hemorrhage Fever (DHF) atau Demam Berdarah Dengue (DBD) adalah penyakit demam akut yang dapat menyebabkan kematian dan disebabkan oleh empat serotype virus dan genus flavivirus, virus RNA dari keluarga falviviradea. Pada akhir tahun 2022, jumlah kasus dengue di Indonesia mencapai 143.000 kasus, dengan angka kejadian dengue terbanyak berada d...

Usutu virus (USUV) is an arbovirus and has emerged as a potential cause of encephalitis in humans and other vertebrates. The increasing detection of USUV in mosquitoes and birds across Africa and Central Europe, along with the lack of specific treatments or vaccines for many encephalitic orthoflaviviruses, underscores the need for focused research....