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Chikungunya and Mayaro infective viruses in components of blood.

OBJECTIVE: Evaluate the infectivity of Alphavirus Chikungunya and Mayaro in blood products in plaque forming units (UFP/ml). BACKGROUND: Arboviruses are responsible for sporadic diseases or epidemics which cause serious public health issues. Due to the high number of asymptomatic infections and high viremia, blood donors may pass on these viruses by transfusion. METHODS/MATERIALS: This study used blood bags that would be discarded after evaluation and certification of the absence of infections. The blood products obtained by centrifuging a unit of whole blood were called blood components. Al…

Rediscovering the chikungunya virus.

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 seq…

A Functional Ubiquitin-Proteasome System is Required for Efficient Replication of New World Mayaro and Una Alphaviruses.

Mayaro (MAYV) and Una (UNAV) are emerging arboviruses belonging to the Alphavirus genus of the Togaviridae family. These viruses can produce febrile disease with symptoms such as fever, headache, myalgia, skin rash and incapacitating poly-arthralgia. Serological studies indicate that both viruses are circulating in different countries in Latin America. Viruses need the host cell machinery and resources to replicate effectively. One strategy to find new antivirals consists of identifying key cellular pathways or factors that are essential for virus replication. In this study, we analyzed the ro…

Deciphering the dark proteome of Chikungunya virus.

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus. The outbreak of CHIKV infection has been seen in many tropical and subtropical regions of the biosphere. Current reports evidenced that after outbreaks in 2005-06, the fitness of this virus propagating in Aedes albopictus enhanced due to the epistatic mutational changes in its envelope protein. In our study, we evaluated the prevalence of intrinsically disordered proteins (IDPs) and IDP regions (IDPRs) in CHIKV proteome. IDPs/IDPRs are known as members of a 'Dark Proteome' that defined as a set of polypeptide segments or whole protein w…

Unbiased Strain-Typing of Arbovirus Directly from Mosquitoes Using Nanopore Sequencing: A Field-forward Biosurveillance Protocol.

The future of infectious disease surveillance and outbreak response is trending towards smaller hand-held solutions for point-of-need pathog … scriptome sequencing on the Oxford Nanopore MinION and shown to contain Everglades Virus (EVEV), an alphavirus in the VEEV serocomplex. Our results demonstrate, for the first time, the use of unbiased sequence-based detection and subtyping of a high-consequence biothreat pathogen directly from an environmental sample using field-forward protocols. The develo …

DNA vaccines for fish: Review and perspectives on correlates of protection.

Recently in 2016, the European Medicines Agency (EMA) recommended granting a marketing authorization in the EU for "Clynav," a DNA vaccine against salmon pancreas disease (salmonid alphavirus-3). Generally, DNA vaccines induce both early and late immune responses in fish that may be protective against disease. Several transcriptomic approaches have been performed to map immunome profiles following DNA vaccination, but the precise immune mechanism(s) that is responsible for protection is not known, although reasonable suggestions have been made. The current review includes an overview on main t…

Diagnostic Methods for CHIKV Based on Serological Tools.

This chapter presents the most commonly used serological methods for the diagnosis of Chikungunya virus (CHIKV) infection in humans. CHIKV is a mosquito-borne Alphavirus widely distributed in the tropical and subtropical regions of Africa, Asia, and America. CHIKV infection in human causes acute febrile illness frequently accompanied by severe joint pain. Most of the infected patients may develop chronic arthralgia that may persist for several months or years. Laboratory diagnosis of CHIKV infection is mainly based on molecular and serological tests. The serological tests represent a valuable …

New hosts for the mite Ornithonyssus bursa in Argentina.

The mite Ornithonyssus bursa (Berlese) (Mesostigmata: Macronyssidae) is considered a poultry pest causing important infestations in chickens and it is considered a potential vector of arbovirus. Despite being considered a common parasite in wild birds, there is scarce published information about its potential hosts and effects on them. Here we present new bird hosts for O. bursa, assess the presence of Alphavirus, Flavivirus and Bunyavirus in mites from three host species, and discuss its potential impact on wild bird populations. We found O. bursa infecting five raptor and six passerine wild …

[Cellular laminin-binding protein and Venezuelan equine encephalomyelitis virus replication in Vero, 293 and 9S2 cells].

The level of laminin-binding protein (LBP) expression on cellular membranes was studied in three cell lines including 293 cells transformed … r development of some new generation of antiviral drugs that would be able to inhibit (enhance) the alphavirus replication in human cells.

Combinations of approved oral nucleoside analogues confer potent suppression of alphaviruses in vitro and in vivo.

Alphaviruses, including chikungunya virus (CHIKV), pose a significant global health threat, yet specific antiviral therapies remain unavailable. We evaluated combinations of three oral directly acting antiviral drugs (sofosbuvir (SOF), molnupiravir (MPV), and favipiravir (FAV)), which are approved for other indications, against CHIKV, Semliki Forest virus (SFV), Sindbis virus (SINV), and Venezuelan Equine Encephalitis virus (VEEV) in vitro and in vivo. We assessed antiviral efficacy in human skin fibroblasts and liver cells, as well as in a mouse model of CHIKV-induced arthritis. In human skin…

Epidemiology of Emergent Madariaga Encephalitis in a Region with Endemic Venezuelan Equine Encephalitis: Initial Host Studies and Human Cross-Sectional Study in Darien, Panama.

BACKGROUND: Neurotropic arboviral infections are an important cause of encephalitis. A zoonotic, vector-borne alphavirus, Madariaga virus (MADV; formerly known as South American eastern equine encephalitis virus), caused its first documented human outbreak in 2010 in Darien, Panama, where the genetically similar Venezuelan equine encephalitis virus (VEEV) is endemic. We report the results of a seroprevalence survey of animals and humans, illustrating contrasting features of MADV and VEEV ecology and epidemiology. METHODS: Small mammals were trapped in 42 sites in Darien, Panama, using Sherman…

Neutralizing antibodies against Chikungunya virus and structural elucidation of their mechanism of action.

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes febrile illness and acute or chronic arthritis. Most therapeutics are still in the pre-clinical stage. In this study, we report the isolation of two neutralizing antibodies, C34 and C37, from a convalescent patient and investigate their mechanisms of action. Both C34 and C37 exhibit high neutralizing activities in vitro and demonstrate protective effects against CHIKV in a female mouse model. Our functional and structural studies reveal a mechanism that inhibits multiple stages of the virus infection cycle. Both antibodies bi…

Динамическое регулирование автофагии во время заражения вирусом Семлики в организме клеток нейробластомы.

Автофагия может защитить от инфекции, доставляя вирусы лизосомам для разложения. Вирус Semliki Forest (SFV) — одиночковый вирус, который широко используется в качестве модели для арбовирусной инфекции и нейронного энцефалита. Здесь мы показываем, что автофагию подавляют в ранние часы заражения СФВ нейронами. Мы также показываем, что переход от автоматического подавления к регулированию между ранними и поздними стадиями проходил через модуляцию млекопитающей цели рэпамицин (mTOR) во время инфекции. На более поздних стадиях инфекции автофагосомы солокации с неструктурными белками SFV предлагают

Совпадение в аннотации оригинала
Autophagy can defend against infection by delivering viruses to lysosomes for degradation. Semliki Forest virus (SFV) is a positive-sense, single-stranded RNA virus of the alphavirus genus which has been used extensively as a model for arbovirus infection and neuronal encephalitis. Here, we show that autophagy is suppressed during the early hours of SFV infe…

Eastern Equine Encephalitis Virus: The Importance of Metabolism and Aging.

Eastern equine encephalitis virus (EEEV) is a mosquito-transmitted alphavirus that, among humans, can cause a severe and often fatal illness. The zoonotic EEEV enzootic cycle involves a cycle of transmission between Culiseta melanura and avian hosts, frequently resulting in spillover to dead-end vertebrate hosts such as humans and horses. Interestingly, it has been described that the W132G mutation of the very low-density lipoprotein receptor (VLDLR), the receptor of EEEV, significantly enhanced the VLDLR-mediated cell attachment of EEEV. The patient's metabolism plays a pivotal role in shapin…

Novel Class of Chikungunya Virus Small Molecule Inhibitors That Targets the Viral Capping Machinery.

Despite the worldwide reemergence of the chikungunya virus (CHIKV) and the high morbidity associated with CHIKV infections, there is no appr … on. In enzymatic assays, CHVB inhibited the methyltransferase and guanylyltransferase activities of alphavirus nsP1 proteins. To conclude, we identified a class of CHIKV inhibitors that targets the viral capping machinery. The potent anti-CHIKV activity makes this chemical scaffold a potential candidate for CHIKV drug development.

Chikungunya as a paradigm for emerging viral diseases: Evaluating disease impact and hurdles to vaccine development.

Chikungunya fever (CHIKF) is an emerging infectious disease caused by an alphavirus transmitted by Aedes spp. mosquitoes. Because mosquito control programs are not highly efficient for outbreak containment, vaccines are essential to reduce the burden of disease. Although no licensed vaccine against CHIKF is yet available, many highly promising candidates are undergoing preclinical studies, and a few of them have been tested in human trials of phase 1 or 2. Here, we review recent findings regarding the need for a CHIKF vaccine and provide an update on vaccines nearing or having entered clinical…

Vector Competence and Capacity of Culex erraticus (Diptera: Culicidae) for Eastern Equine Encephalitis Virus in the Southeastern United States.

Field studies of the ecology of eastern equine encephalitis virus (EEEV; family Togaviridae, genus Alphavirus) in the southeastern United States have demonstrated that Culex erraticus (Dyar and Knab) is the most common mosquito at many enzootic sites and is often infected with the virus. However, the competence of Cx. erraticus for EEEV has not been explored in detail. Culex erraticus females were collected from the field and fed upon EEEV-infected chicks. The infected mosquitoes were provided honey for nutrition and to monitor for time to infectiveness. Of the mosquitoes that survived the 14-…

Chikungunya virus: recent advances in epidemiology, host pathogen interaction and vaccine strategies.

The Chikungunya virus is a re-emerging alphavirus that belongs to the family Togaviridae. The symptoms include fever, rashes, nausea and joint pain that may last for months. The laboratory diagnosis of the infection is based on the serologic assays, virus isolation and molecular methods. The pathogenesis of the Chikungunya viral infection is not completely understood. Some of the recent investigations have provided information on replication of the virus in various cells and organs. In addition, some recent reports have indicated that the severity of the disease is correlated with the viral lo…

O'nyong-nyong fever in south-central Uganda, 1996-1997: clinical features and validation of a clinical case definition for surveillance purposes.

O'nyong-nyong (ONN) fever, caused by infection with a mosquito-borne central African alphavirus, is an acute, nonfatal illness characterized by polyarthralgia. During 1996-1997, south-central Uganda experienced the second ONN fever epidemic ever recognized. Among 391 persons interviewed and sampled, 40 cases of confirmed and 21 of presumptive, well-characterized acute, recent, or previous ONN fever were identified through active case-finding efforts or during a household serosurvey and by the application of clinical and laboratory criteria. Among confirmed cases, the knees and ankles were the …