Next article cryoem structure of chikungunya virus in complex with. Chikungunya virus infection is a rapidonset, febrile disease with intense asthenia, arthralgia, myalgia, headache, and rash. Chikungunya virus capsid protein contains nuclear import and. Two changes to the structure of e1 makes the virus more likely to enter mosquito cells and replicate after the insect has fed on the blood of an infected person. Biology and pathogenesis of chikungunya virus nature. The pathogenesis of chikungunya infection in humans is still poorly understood, despite recent outbreaks. The final complex structure was determined to a resolution of 3. Chikungunya virus infectivity, rna replication and nonstructural polyprotein processing depend on the nsp2 proteases active site cysteine residue. Other symptoms may include headache, muscle pain, joint swelling, and a rash. Two changes to the structure of e1 makes the virus more likely to enter mosquito cells and.
Global risk outbreaks have occurred in parts of africa, europe. Chikungunya virus is passed to humans when a bite from an infected mosquito breaks the skin and introduces the virus into the body. Chikungunya virus infection in indonesia bmc infectious diseases. The structure of this ternary complex revealed the molecular basis for. It is maintained in nature through both urban and sylvatic cycles, involving mosquito vectors and human or vertebrate animal hosts. In recent decades it has expanded to several areas previously known to be aedesfree. Rarely, it can spread from mother to newborn around the time of birth. Crystal structure of chikungunya virus nsp2 cysteine protease reveals a putative flexible loop blocking its active site. Chikungunya virus an overview sciencedirect topics. Epidemics since 2005 have spread from africa and asia, and through europe, and an ongoing epidemic has caused nearly two million cases in the americas. Chikungunya virus is known to be the cause of chikungunya disease. Chikungunya virus baylor college of medicine houston, texas. A free powerpoint ppt presentation displayed as a flash slide show on id. Alphavirus including 29 viruses within the genus comprising three groups.
There are 29 different types of alphaviruses that cause diseases in humans and other. One specific emerging arbovirus that will be discussed in this paper is called the chikungunya virus. Chikungunya virus consists of a single stranded positive sense rna. Structure and function of alphavirus proteases pdf free. Molecular basis of arthritogenic alphavirus receptor mxra8. Chikungunya is a virus passed to humans by the bite of infected mosquitoes. Chikungunya virus chikv is an alphavirus that is primarily transmitted by aedes species mosquitoes. Ppt chikungunya an update powerpoint presentation free to. Zika virus structure revealed national institutes of. You are using a web browser that we do not support.
Pdf 3d structure development of chikungunya virus and. Chikungunya virus chikv is an rna alphavirus belonging to the togaviridae family, first identified in tanzania in 1952. Advances in biology pathogenesis and treatment content this book describes the molecular biology, pathogenesis, epidemiology, and potential strategies for control of chikungunya virus chikv infection. Pdf crystal structure of chikungunya virus nsp2 cysteine. It may also possibly spread through infected blood. Pdf chikungunya virus chikv is a reemerging, pathogenic alphavirus. After autoproteolytic cleavage, the chikv capsid protein cp is involved in rna binding and assembly of the viral particle. Chikungunya is an arthropodborne virus transmitted by aedes mosquito bites. This book describes the molecular biology, pathogenesis, epidemiology, and potential strategies for control of chikungunya virus chikv infection. Chikungunya is spread by mosquitoes and is characterised by severe joint pains with fever. At the time, little was known about the biology and pathogenesis of this virus. During december 2016may 2017, an outbreak of chikungunya virus infection occurred across pakistan. Chikungunya virus chikv is a mosquitotransmitted alphavirus that causes explosive epidemics of a severe febrile illness characterized by debilitating polyarthralgia, polyarthritis, tenosynovitis, myalgia, headache, and rash weaver and lecuit, 2015. Some alphaviruses are found to harbor nuclear localization signals.
Diagnostic tests include virus isolation from serum, rtpcr, igmspecific antibody by eia or hi, detection of neutralizing antibody by hemagglutination inhibition assay hi, and demonstration of a rise in serum igg antibody titer between acute infection and convalescence. Chikungunya is an infection caused by the chikungunya virus chikv. A person with no recent history of travel to an area with the virus who gets bitten by a mosquito infected with chikungunya virus where they live, work or play. Chikungunya, the clinical illness caused by chikv, is characterized by a rapid onset of high fever and. Aug 01, 2019 chikungunya fever is a selfremitting febrile viral illness that has been associated with frequent outbreaks in tropical countries of africa and southeast asia. Four nonstructural proteins and five structural proteins are the elementary units of chikungunya virus that carry out replication. Chikungunya virus chikv belongs to the alphavirus family, the members of which have enveloped icosahedral capsids.
Outbreaks have occurred in countries in africa, asia, europe, and the indian and pacific oceans. Advances in the biology imaging and therapies for glioblastoma pdf influenza pathogenesis and control volume i emerging and evolving topics in multiple sclerosis pathogenesis and treatments chikungunya virus download ebook chronic hepatitis c virus. Symptoms are fever, joint and muscle pain, headache, nausea, fatigue and rash. This study provides baseline data on the virus strain and emphasizes the need for active surveillance and implementation of preventive interventions to contain future outbreaks. There have also been cases in madagascar, mayotte and the seychelles. There have been outbreaks of chikungunya virus in africa, asia, europe, the indian and pacific oceans, the caribbean, and central and south america. The nonstructural proteins nsp1, nsp2, nsp3 and nsp4 are encoded by orf1 at 5.
Pdf function of chikungunya virus structural proteins. The symptoms are very similar to dengue, which is seen in the same areas as where chikungunya virus is present and also which is why chikungunya virus is often misdiagnosed as dengue. Some alphaviruses are found to harbor nuclear localization signals nls and. Rossmanna,1 adepartment of biological sciences, purdue university, west lafayette, in 47907. The monomeric cp is approximately 30 kda in size and is small enough for passive transport through nuclear pores. Viruses free fulltext tropism of the chikungunya virus. This mosquitoborne alphavirus has spread throughout the caribbean and. Chikungunya is a virus that spread by the same kinds of mosquitoes that spread dengue and zika virus. Chikungunya virus chikv is a reemerging mosquitotransmitted alphavirus. Chikungunya virus chikv, a reemerging arbovirus, causes a crippling musculoskeletal inflammatory disease in humans characterized by fever, polyarthralgia, myalgia, rash, and headache. These typically occur two to twelve days after exposure.
Phylogenetic analysis has revealed 3 distinct groups based on partial sequences of ns4 and e1 genes. The photo on the right is the structure of a togaviridae family virus and represents the photo of a chikungunya virus. Chikungunya virus pdf this publication describes the molecular biology, pathogenesis, epidemiology, and potential strategies for management of chikungunya virus chikv disease. Chikungunya virus iris paho home pan american health. Although chikv was first isolated in 1953, its pathogenesis was only more extensively studied. Using as examples zika, chikungunya and dengue, we summarise current knowledge on characteristics of the viruses and their transmission, clinical features, laboratory.
There are several vaccine candidates in preclinical and clinical development for the chikungunya virus. A virus spread through aedes species mosquito bites. The multifunctional helicaseprotease protein nsp2 of chikungunya virus chikv plays vital roles in viral rna replication and virus host interactions. Dec 26, 2017 chikungunya virus chikv belongs to the alphavirus family, the members of which have enveloped icosahedral capsids. Unlike semliki forest virus and sindbis virus, subgenomic rna of chikungunya virus does not have a stable stemloop structure, the socalled capsid enhancer, at its 5. During epidemics and endemic circulation, chikv is transmitted by aedes aegypti and, to a lesser extent, by a. Polyacrylamide gel analysis of the structural proteins of african and asian strains of chikungunya virus, an alphavirus, showed that both strains contain three structural proteins. It offers insight into the structure and functions of chikv proteins as they relate to host response, interaction with the arthropod vector, and. Here we report the complete genome sequence of a chikungunya virus strain, gd052010, isolated in 2010 from a patient with chikungunya fever in guangdong, china. Using as examples zika, chikungunya and dengue, we summarise current knowledge on characteristics of the viruses and their transmission, clinical features, laboratory diagnosis, burden.
Develop planning and decisionmaking structures for responding to a po. Following inoculation into the skin, chikv replicates locally and ultimately produces a high titer viremia that facilitates a humanmosquitohuman transmission cycle. Local transmission means that mosquitoes in the area have been infected with the virus and are spreading it to people. The virus, like others, does not have a welldefined cure. Complete genome sequence of a chikungunya virus isolated. A detailed account of the epidemiological prognosis and the clinical syndrome of chikv disease is supplied. A risk to anyone traveling to a region of the world where chikungunya virus is found. Chikungunya is a member of the alphavirus genus in the family togaviridae. Infection with chikv typically causes a selflimiting febrile illness, chikungunya fever chikf, characterized by chronic, severe joint pain. The sequence information is important for surveillance of this emerging arboviral infection in china. A detailed account of both the epidemiological outlook and the clinical syndrome of chikv. The structure has a diameter of about 50nm to 70nm.
A viral mutation has allowed aedes albopictus to become the preferred vector extending the geographic spread of the. Symptoms and signs of chikv infection include high fever, severe joint pain, muscle pain, and rash. Other symptoms may include headache, muscle pain, joint swelling, or rash. Chikungunya virus is a reemerging alphavirus that recently caused an epidemic in countries of the indian ocean. Chikungunya virus chikv is an emerging mosquitoborne alphavirus that has caused widespread outbreaks of debilitating human disease in the past five years. The eastcentralsouth african genotype was predominant. Chikungunya virus chikv is an alphavirus of the togaviridae family. Aedes mosquitoes also spread dengue and zika viruses. Chikungunya virus baylor college of medicine houston. Chikungunya virus and the global spread of a mosquito. Chikungunya virus is an alpha virus that belongs to the togaviridae family. The name chikungunya pronounced chikengunye is an african word meaning bent over in pain.
Chikungunya as a paradigm for emerging viral diseases. Chikungunya virus chikv disease agent characteristics. Chikungunya virus chikv is a reemerging mosquitoborne virus that displays a large cell and organ tropism, and causes a broad range of clinical symptoms in humans. This insectborne virus, abbreviated as chikv, is native to africa and asia pardigon, 2009. It is a singlestranded rna virus and is approximately 11. Chikungunya is caused by the chikungunya virus chikv, an arthropodborne virus arbovirus. Following diagram shows the classification of chikungunya virus.
It offers insight into the structure and functions of chikv proteins as they relate to host response, interaction with the arthropod vector, and vaccination. Chikungunya virus capsid protein contains nuclear import. Human to human transmission is currently not proven to be possible. The structure provides clues to understanding how zika virus enters human cells and suggests ways to design drugs or vaccines to combat the virus. During the years of 2005 and 2006, the chikungunya virus has affected over a million people in the indian ocean islands including india pardigon 2009. It is transmitted by the virus carrying mosquito known as aedes cdc. Mxra8 is a receptor for multiple arthritogenic alphaviruses that cause debilitating acute and chronic musculoskeletal disease in humans. Chikungunya nowcast for the americas chikungunya virus cdc. Cryoem structure of chikungunya virus in complex with the.
This is a pdf file of an unedited manuscript that has been accepted for. Furthermore, domains b on the e2 glycoproteins have less free. There are 29 different types of alphaviruses that cause diseases in humans and other mammals. Thus, how active translation of chikungunya virus rna is maintained remains unclear. We determined the crystal structure of the helicase part of the chikv nsp2 nsp2h bound to the conserved 3. Chikungunya virus belongs to the genus alphavirus in the family togaviridae. Chikungunya virus, infectious agent of the genus alphavirus in the family togaviridae. Chikungunya fever is contracted via a humanmosquitohuman pathway where the mosquito obtains the virus from biting an infected human and transmits the virus by biting a noninfected human. The structure was determined by molecular replacement mr, using the abovedescribed mmxra8 structure and the previously reported chikv e structure voss et al. Download chikungunya virus pdf free download and read. Though reports of an illness consistent with chikungunya date back over 200 years, chikv only gained worldwide attention during a massive pandemic that began in east africa in 2004.
The only way to differentiate the difference between dengue and chikungunya virus is by performing a blood test elisa, which can be time consuming. The virus was initially isolated from a tanzanian patient in 1953. Jan 30, 2019 chikungunya is a virus that spread by the same kinds of mosquitoes that spread dengue and zika virus. We mutated the proteolytic cleavage site on e2 envelope protein, which is necessary in initiating the maturation process.
Chikungunya an update a free powerpoint ppt presentation displayed as a flash slide show on id. Chikungunya virus chikv, a mosquitotransmitted alphavirus. Chikungunya is a relatively rare form of viral fever debilitating nonfatal viral illness. Ppt chikungunya an update powerpoint presentation free. Pdf structural and phenotypic analysis of chikungunya virus rna.
Thus, insights into the structural properties of the dengue virion may be transferable to medically relevant alphaviruses e. Sep 17, 2019 in late 20, the first local transmission of chikungunya virus in the americas was identified in caribbean countries and territories. It offers insight into the structure and functions of chikv proteins as they relate to host. Know more about the symptoms and treatment of chikungunya in this presentation ppt. A nat screening test was implemented on reunion island. The maturation process of alphaviruses involves proteolysis of some of the structural proteins before assembling with nucleocapsids to produce mature virions. Its name is derived from a word in the makonde language that means contorted or bent, and it refers to the stooped appearance of its victims who suffer from severe joint pain. The illness has only recently become a concern in western countries and temperate zones around the world. Crystal structure of chikungunya virus nsp2 cysteine protease reveals a putative flexible loop blocking its active site article pdf available in international journal of biological. The most common symptoms of infection are fever and joint pain. Structural studies of chikungunya virus maturation pnas. The recent emergence and reemergence of viral infections transmitted by vectorszika, chikungunya, dengue, japanese encephalitis, west nile, yellow fever and othersis a cause for international concern. The mosquitotransmitted chikungunya virus chikv is associated with increased. Chikungunya virus chikv is an alpha virus and female mosquitoes of aedes species are blamable for the virus transmission, particularly by aedes aegyptius and aedes albopictus.
Global emerging health threats is the goto resource for both historical and current information on this important virus that is rapidly increasing its global range. Chikungunya virus advances in biology, pathogenesis, and. Structural studies of chikungunya virus maturation moh lan yapa,b, thomas klosea, akane urakamic, s. Particularly, the condition is transmitted in humans through the a aegypti and a albopictus which are the extrinsic hosts of the chikungunya virus. The role of the membrane in the structure and biophysical.
A crippling mosquitoborne virus with a tonguetwisting name chikungunya has spread to the caribbean, and u. Chikv is transmitted by aedes species of mosquitoes and is capable of an epidemic, urban transmission cycle with high rates of infection. Chikungunya is a disease that is caused by the chikungunya virus which is transmitted to humans by infected mosquitoes. Replication at other tissues leads to the viremic phase of the disease, which. Pdf chikungunya is a reemerging arthropodborne viral disease caused by. Chikungunya virus is spread to people by the bite of an infected mosquito. In recent decades the aedes mosquitoes carrying chikungunya have spread to the european region. The zika virus surface is similar to that of dengue and related viruses at the nearatomic level, researchers found, but with a notable difference. Chikungunya virus chikv is a mosquitoborne virus responsi.
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