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1.
São Paulo; SES/SP; nov. 2021. 56 p. tab, ilus, graf, mapas.
Non-conventional in Portuguese | LILACS, ColecionaSUS, SES-SP, CONASS, SESSP-CTDPROD, SES-SP, SESSP-ACVSES | ID: biblio-1344584
3.
Article in English | WPRIM | ID: wpr-816639

ABSTRACT

Mayaro virus (MAYV) is a mosquito-transmitted alphavirus that produces an acute, usually non-fatal, febrile illness including Mayaro fever. Like other alphaviruses, the MAYV E1 and E2 envelope glycoproteins are major viral surface antigens that play a key role in host recognition and infection. Here, we report expression and purification methods for recombinant MAYV E1 (rE1) and rE2 using a baculovirus system. Enzyme-linked immunosorbent assays (ELISA) revealed that rE1 and rE2 were antigenic and reacted with human anti-MAYV IgG and IgM. Cross-reactivity was also confirmed with human anti-Chikungunya virus (CHIKV) IgG and IgM. Furthermore, we developed an immunochromatographic strip test (IST) with rE2 to diagnose MAYV infection. Thus, purified rE2 may be valuable tool for rapidly diagnosing MAYV infection.


Subject(s)
Alphavirus , Antigens, Surface , Baculoviridae , Enzyme-Linked Immunosorbent Assay , Fever , Glycoproteins , Humans , Immunoglobulin G , Immunoglobulin M
4.
Rev. Hosp. Clin. Univ. Chile ; 30(2): 109-119, 2019. ilus
Article in Spanish | LILACS | ID: biblio-1052721

ABSTRACT

Chikungunya virus is an alphavirus, member of the Togaviridae family, first discovered in Africa in 1952. Since then it caused sporadic outbreaks in Africa and Asia, but since 2000, outbreaks had been more frequent, being identified in Europe, America and the Caribbean. Chikungunya virus can cause chronic and incapacitating arthralgia, with an important morbidity, being considered as a relevant re-emerging public health problem. This review intends to update our knowledge in epidemiology, transmission, pathogenesis, treatment and vaccination strategies of Chikungunya virus. (AU)


Subject(s)
Humans , Male , Female , Chikungunya virus/pathogenicity , Chikungunya Fever/prevention & control , Alphavirus , Chikungunya Fever/physiopathology , Chikungunya Fever/therapy , Chikungunya Fever/epidemiology
5.
Rev. Soc. Bras. Med. Trop ; 51(5): 584-590, Sept.-Oct. 2018. tab, graf
Article in English | LILACS | ID: biblio-957459

ABSTRACT

Abstract INTRODUCTION: The Mayaro virus (MAYV), which is an arbovirus closely related to the Chikungunya virus, causes a dengue-like acute illness that is endemic to Central and South America. We investigated the anti-MAYV activity of prostaglandin A1 (PGA1), a hormone which exhibits antiviral activity against both ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) viruses. Further, we examined the effects of inducting the stress protein HSP70 following PGA1 treatment. METHODS: Hep-2 cells infected with MAYV were treated with PGA1 (0.1-6μg/ml) 12h before infection and for different periods post-infection. Inhibition of viral replication inhibition was analyzed via viral titer determination, whereas the effect of PGA1 on viral morphogenesis was examined via transmission electron microscopy (TEM). Autoradiography (with 35S methionine labeling) and western blotting were used to assess the effect of PGA1 treatment on viral and cellular protein synthesis, and on HSP70 induction, respectively. RESULTS: PGA1 strongly reduced viral replication in Hep-2 cells, particularly when added during the early stages of viral replication. Although PGA1 treatment inhibited viral replication by 95% at 24 hours post-infection (hpi), viral structural protein synthesis was inhibited only by 15%. TEM analysis suggested that PGA1 inhibited replication before viral morphogenesis. Western blot and densitometry analyses showed that PGA1 treatment increased HSP70 protein levels, although this was not detectable via autoradiography. CONCLUSIONS: PGA1 inhibits MAYV replication in Hep-2 cells at early stages of viral replication, prior to production of viral structural proteins, possibly via HSP70 induction.


Subject(s)
Humans , Animals , Cattle , Prostaglandins A/pharmacology , Virus Replication/drug effects , Alphavirus/drug effects , HSP70 Heat-Shock Proteins/pharmacology , Epithelial Cells/virology , Antiviral Agents/pharmacology , Cell Line , Blotting, Western , Alphavirus/ultrastructure , Microscopy, Electron, Transmission , Electrophoresis, Polyacrylamide Gel , Epithelial Cells/ultrastructure
6.
Braz. j. infect. dis ; 21(5): 540-544, Sept.-Oct. 2017. graf
Article in English | LILACS | ID: biblio-888906

ABSTRACT

Abstract Mayaro virus is an alphavirus from the Togaviridae family and is transmitted mainly by Hemagogus mosquitoes. This virus circulates in high-density tropical forests or rural areas of Central and South America causing a disease characterized by high-grade fever, maculopapular skin rash and marked arthralgia that, in some patients, can persist for long periods after infection and may be misinterpreted as chikungunya. Although only a few outbreaks involving this virus have been reported, in the last years the number of Mayaro virus infections has increased in the central and northern regions of Brazil. In this review, we describe the reported prevalence of this infection over the years and discuss the circumstances that can contribute to the establishment of an urban mayaro virus epidemic in Brazil and the problems encountered with the specific diagnosis, especially the antigenic cross-reactivity of this pathogen with other viruses of the same family.


Subject(s)
Humans , Animals , Alphavirus Infections/epidemiology , Alphavirus/classification , Urban Population , Brazil/epidemiology , Disease Outbreaks , Mosquito Vectors/virology
7.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 15(2): 30-36, ago. 2017. ilus
Article in Spanish | LILACS, BDNPAR | ID: biblio-869122

ABSTRACT

El género Alphavirus está constituido por virus de ARN de los cuales, varias especies son causantes de enfermedades humanas y animales como los virus chikungunya, Mayaro y los virus de encefalitis equinas, por lo que son considerados un problema de salud pública a nivel regional. En Paraguay han sido reportadas infecciones humanas por chikungunya pero son necesarios más estudios para ampliar conocimientos sobre circulación y ecoepidemiología de los alfavirus. La transcripción reversa de ARN seguida de una reacción en cadena de la polimerasa (RT-PCR) anidada es de gran utilidad como herramienta diagnóstica y en la vigilancia epidemiológica. El objetivo de este estudio fue definir las condiciones óptimas de reacción y determinar el límite de detección para una RT-PCR anidada para la detección genérica de alfavirus. El límite de detección obtenido, de 0,47 UFP/mL, indica una alta sensibilidad, pudiéndose aplicar la técnica a muestras humanas y animales de suero, líquido cefalorraquídeo, órganos y a pooles de mosquitos. Este trabajo servirá de base a otros estudios de detección e identificación de especies de alfavirus circulantes en nuestro país, lo que contribuiría a fortalecer su vigilancia y prevención.


The genus Alphavirus consists of RNA viruses of which several species areresponsible for human and animal diseases, such as chikungunya, Mayaro and equineencephalitis viruses, and are therefore considered a regional public health problem. InParaguay, human infections have been reported by chikungunya, but more studies areneeded to increase knowledge on the circulation and ecoepidemiology of alphaviruses.Reverse RNA transcription followed by a nested polymerase chain reaction (RT-PCR) isvery useful as a diagnostic tool and in epidemiological surveillance. The objective ofthis study was to define optimal reaction conditions and to determine the limit ofdetection for a nested RT-PCR for generic alphavirus detection. The detection limitobtained, of 0,47 PFU/mL, indicate high sensitivity, and the possibility of applying thetechnique to human and animals samples of serum, cerebrospinal fluid, organs andmosquito pools. This work will serve as a basis for other studies of detection andidentification of alphavirus species circulating in our country, which would helpstrengthen the surveillance and prevention.


Subject(s)
Humans , Alphavirus , Alphavirus Infections , Reverse Transcriptase Polymerase Chain Reaction , Public Health
8.
Mem. Inst. Oswaldo Cruz ; 112(7): 510-513, July 2017. tab, graf
Article in English | LILACS | ID: biblio-841812

ABSTRACT

ABSTRACT We describe a sensitive method for simultaneous detection of Oropouche and Oropouche-like viruses carrying the Oropouche S segment, as well as the Mayaro virus, using a multiplexed one-step reverse transcription real-time polymerase chain reaction (RT-qPCR). A chimeric plasmid containing both Mayaro and Oropouche targets was designed and evaluated for the in vitro production of transcribed RNA, which could be easily used as a non-infectious external control. To track false-negative results due to PCR inhibition or equipment malfunction, the MS2 bacteriophage was also included in the multiplex assay as an internal positive control. The specificity of the multiplex assay was evaluated by Primer-Blast analysis against the entire GenBank database, and further against a panel of 17 RNA arboviruses. The results indicated an accurate and highly sensitive assay with amplification efficiency greater than 98% for both targets, and a limit of detection between two and 20 copies per reaction. We believe that the assay described here will provide a tool for Mayaro and Oropouche virus detection, especially in areas where differential diagnosis of Dengue, Zika and Chikungunya viruses should be performed.


Subject(s)
Humans , Orthobunyavirus/classification , Orthobunyavirus/genetics , Bunyaviridae Infections/diagnosis , Bunyaviridae Infections/virology , Alphavirus Infections/diagnosis , Alphavirus Infections/virology , Alphavirus/classification , Alphavirus/genetics , Reverse Transcriptase Polymerase Chain Reaction , Multiplex Polymerase Chain Reaction
9.
Article in English | WPRIM | ID: wpr-91209

ABSTRACT

Getah virus (GETV) infection causes sporadic outbreaks of mild febrile illness in horses and reproductive failure in pigs. In this study, we established a reverse transcription polymerase chain reaction (RT-PCR) method to detect GETV from suspected virus-infected samples. The reaction conditions were optimized and validated by using RNA extracted from GETV propagated in cell culture. A GETV-specific GED4 primer set was designed and used to amplify a 177 bp DNA fragment from a highly conserved region of the E1 glycoprotein gene in the GETV genome. RT-PCR performed with this primer set revealed high sensitivity and specificity. In the sensitivity test, the GED4 primer set detected GETV RNA at the level of 10(2.0) TCID₅₀/mL. In the specificity test, the GED4 primer set amplified only a single band of PCR product on the GETV RNA template, without non-specific amplification, and exhibited no cross-reactivity with other viral RNAs. These results suggest that this newly established RT-PCR method is useful for accurate identification of GETV infection in animals.


Subject(s)
Alphavirus , Animals , Cell Culture Techniques , Diagnosis , Disease Outbreaks , DNA , Genome , Glycoproteins , Horses , Livestock , Methods , Polymerase Chain Reaction , Reverse Transcription , RNA , RNA, Viral , Sensitivity and Specificity , Swine
10.
Braz. j. microbiol ; 47(supl.1): 38-50, Oct.-Dec. 2016. graf
Article in English | LILACS | ID: biblio-839330

ABSTRACT

ABSTRACT Arboviruses pose a serious threat to public health worldwide, overloading the healthcare system and causing economic losses. These viruses form a very diverse group, and in Brazil, arboviruses belonging to the families Flaviviridae and Togaviridae are predominant. Unfortunately, the number of arboviruses increases in proportion with factors such as deforestation, poor sanitation, climate changes, and introduction of new viruses like Chikungunya virus and Zika virus. In Brazil, dengue is endemic, along with the presence of other arboviruses. The situation is complicated by the scarcity of diagnostic infrastructure and the absence of approved vaccines for these diseases. Disease control, thus, relies solely on vector control. Therefore, enhanced clinical knowledge and improved general awareness about these arboviruses are indispensable to tackle diagnostic inadequacies.


Subject(s)
Humans , Animals , Virus Diseases/transmission , Virus Diseases/virology , Insect Vectors/virology , Culicidae/virology , Brazil/epidemiology , Virus Diseases/diagnosis , Virus Diseases/epidemiology , Alphavirus Infections/diagnosis , Alphavirus Infections/transmission , Alphavirus Infections/epidemiology , Alphavirus Infections/virology , Alphavirus/classification , Alphavirus/physiology , Dengue/transmission , Dengue/epidemiology , Dengue/virology , Dengue Virus/classification , Dengue Virus/physiology , Zika Virus Infection/diagnosis , Zika Virus Infection/transmission , Zika Virus Infection/epidemiology , Zika Virus Infection/virology
11.
Rev. Soc. Bras. Med. Trop ; 49(5): 648-652, Sept.-Oct. 2016. graf
Article in English | LILACS | ID: lil-798121

ABSTRACT

Abstract Arboviruses impose a serious threat to public health services. We report a case of a patient returning from a work trip to the Amazon basin with myalgia, arthralgia, fever, and headache. During this travel, the patient visited riverside communities. Both dengue and Chikungunya fevers were first suspected, tested for, and excluded. Mayaro fever was then confirmed by reverse transcription polymerase chain reaction followed by next-generation sequencing and phylogenetic reconstruction. The increased awareness of physicians and consequent detection of Mayaro virus in this case was only possible due a previous surveillance program with specific health personnel training about these neglected arboviruses.


Subject(s)
Humans , Male , Adult , HIV Infections , Alphavirus Infections/diagnosis , Alphavirus/genetics , Phylogeny , Alphavirus Infections/virology , Alphavirus/classification , Reverse Transcriptase Polymerase Chain Reaction , Diagnosis, Differential , Chikungunya Fever/diagnosis
12.
Mem. Inst. Oswaldo Cruz ; 111(10): 625-634, Oct. 2016. tab, graf
Article in English | LILACS | ID: lil-796902

ABSTRACT

Arboviruses belonging to the genera Flavivirus and Alphavirus were detected in mosquitoes in a rural area of San Bernardo del Viento (Córdoba, Colombia). A total of 22,180 mosquitoes were collected, sorted into 2,102 pools, and tested by generic/nested reverse transcription-polymerase chain reaction. Venezuelan equine encephalitis virus, dengue virus, West Nile virus, St. Louis encephalitis virus, yellow fever virus, and Culex flavivirus were detected and identified by sequencing. The detection of arboviral pathogens in this zone represents possible circulation and indicates a human health risk, demonstrating the importance of virological surveillance activities.


Subject(s)
Humans , Animals , Female , Alphavirus/genetics , Culicidae/virology , Flavivirus/genetics , Alphavirus/classification , Alphavirus/isolation & purification , Caribbean Region , Colombia , Flavivirus/classification , Phylogeny , Reverse Transcriptase Polymerase Chain Reaction , Rural Population
13.
Mem. Inst. Oswaldo Cruz ; 111(1): 20-29, Jan. 2016. tab, graf
Article in English | LILACS | ID: lil-771080

ABSTRACT

This study aimed to verify the diversity of Culicidae species and their frequency of infection with flaviviruses and alphaviruses in Cuiabá, state of Mato Grosso, Brazil. Mosquitoes were captured with Nasci aspirators and hand net in 200 census tracts, identified alive at species level and pooled in one-20 (11,090 mosquitoes, 14 species). Female pools (n = 610) were subjected to multiplex seminested-reverse transcription-polymerase chain reaction (RT-PCR) for 11 flavivirus and five alphavirus. Positive pools were tested by single RT-PCR followed by nucleotide sequencing, by RT-PCR for E1 gene [Mayaro virus (MAYV)] and by inoculation in Vero cells (MAYV) or C6/36 cells (flaviviruses). One/171 Aedes aegypti was positive for dengue virus (DENV)-1, 12/403 Culex quinquefasciatus, and four/171Ae. aegypti for MAYV, which was isolated from two pools containing two nonengorged females of Ae. aegypti and two ofCx. quinquefasciatus. DENV-4 was detected in 58/171 pools of Ae. aegytpi, 105/403 Cx. quinquefasciatus, two/five Psorophora sp., two/11 Psorophora varipes/Psorophora albigenu, one/one Sabethes chloropterus, two/five Culex bidens/Culex interfor, and one/one Aedes sp. DENV-4 was isolated from two pools containing three and 16 nonengorged Cx. quinquefasciatus females. Phylogenetic analysis revealed MAYV belongs to genotype L, clustering with human samples of the virus previously identified in the city. Cuiabá has biodiversity and ecosystem favourable for vector proliferation, representing a risk for arbovirus outbreaks.


Subject(s)
Animals , Female , Humans , Alphavirus/isolation & purification , Culicidae/virology , Dengue Virus/isolation & purification , Insect Vectors/virology , Alphavirus/genetics , Brazil , Culicidae/classification , Dengue Virus/genetics , Genotype , Insect Vectors/classification , Multiplex Polymerase Chain Reaction , Phylogeny , Reverse Transcriptase Polymerase Chain Reaction , Seasons
14.
Biol. Res ; 49: 1-8, 2016. ilus, graf, tab
Article in English | LILACS | ID: biblio-950865

ABSTRACT

BACKGROUND: New sequencing technologies have opened the way to the discovery and the characterization of pathogenic viruses in clinical samples. However, the use of these new methods can require an amplification of viral RNA prior to the sequencing. Among all the available methods, the procedure based on the use of Phi29 polymerase produces a huge amount of amplified DNA. However, its major disadvantage is to generate a large number of chimeric sequences which can affect the assembly step. The pre-process method proposed in this study strongly limits the negative impact of chimeric reads in order to obtain the full-length of viral genomes. FINDINGS: Three different assembly softwares (ABySS, Ray and SPAdes) were tested for their ability to correctly assemble the full-length of viral genomes. Although in all cases, our pre-processed method improved genome assembly, only its combination with the use of SPAdes allowed us to obtain the full-length of the viral genomes tested in one contig. CONCLUSIONS: The proposed pipeline is able to overcome drawbacks due to the generation of chimeric reads during the amplification of viral RNA which considerably improves the assembling of full-length viral genomes.


Subject(s)
DNA-Directed RNA Polymerases/genetics , RNA, Viral , Genome, Viral , Sequence Analysis, RNA/methods , Virus Assembly , Nucleic Acid Amplification Techniques/methods , Reference Values , Software , Central African Republic , Reproducibility of Results , Alphavirus/genetics , Mengovirus/genetics , Computational Biology , Contig Mapping
15.
Article in English | WPRIM | ID: wpr-153899

ABSTRACT

Getah virus (GETV) is a member of the genus Alphavirus in the family Togaviridae. GETV infection can occur in a wide range of vertebrate species, and the virus has been known for a pathogen of horses and pigs. To rapidly and accurately diagnose GETV infection of a racehorse, an indirect ELISA (I-ELISA) was developed in the present study for detection of antibodies to GETV in serum samples. To evaluate the developed I-ELISA, a total of 240 serum samples from Thoroughbred racehorses raised in Korea were screened in parallel by a serum neutralization (SN) test. The developed I-ELISA exhibited an efficacy comparable to that of the SN test in terms of a high diagnostic sensitivity (86.3%) and specificity (94.5%) at a cut-off absorbance value of 0.25. In addition, our results showed that the developed I-ELISA had a significant correlation with the SN test (r = 0.91; p < 0.05). Taken together, our findings suggest that the I-ELISA developed in this study is a valuable diagnostic tool for the screening of horses suspected to be infected with GETV.


Subject(s)
Alphavirus , Antibodies , Enzyme-Linked Immunosorbent Assay , Horses , Humans , Korea , Mass Screening , Sensitivity and Specificity , Swine , Togaviridae , Vertebrates
16.
Article in English | WPRIM | ID: wpr-8378

ABSTRACT

Various new technologies have been applied for developing vaccines against various animal diseases. Virus-like particle (VLP) vaccine technology was used for manufacturing the porcine circovirus type 2 and RNA particle vaccines based on an alphavirus vector for porcine epidemic diarrhea (PED). Although VLP is classified as a killed-virus vaccine, because its structure is similar to the original virus, it can induce long-term and cell-mediated immunity. The RNA particle vaccine used a Venezuela equine encephalitis (VEE) virus gene as a vector. The VEE virus partial gene can be substituted with the PED virus spike gene. Recombinant vaccines can be produced by substitution of the target gene in the VEE vector. Both of these new vaccine technologies made it possible to control the infectious disease efficiently in a relatively short time.


Subject(s)
Alphavirus , Animal Diseases , Animals , Circovirus , Communicable Diseases , Diarrhea , Encephalitis Virus, Venezuelan Equine , Encephalomyelitis, Equine , Immunity, Cellular , Porcine epidemic diarrhea virus , RNA , Vaccines , Vaccines, Synthetic , Vaccines, Virus-Like Particle , Venezuela
17.
Rev. MVZ Córdoba ; 20(supl.1): 4861-4863, Dec. 2015.
Article in English | LILACS, COLNAL | ID: lil-769244

ABSTRACT

In 1780, Philadelphia suffered an unusual outbreak of hemorrhagic fever, which years later was identified as dengue (1). One hundred years later, in Memphis, 1500 people died from yellow fever, which caused residents to abandoned the city (2). Even though these stories may seem anecdotes, they show how dramatic hemorrhagic arbovirus outbreaks can be. The tropic host arboviruses such as Chikungunya (CHIKV), Dengue, and Zika (ZIKV); but there are others, such as Mayaro, Oropuche, and Bussuquara, among others, which have still not been studied in depth by the public health systems of our countries.


Subject(s)
Alphavirus , Chikungunya virus , Viruses
19.
Article in English | WPRIM | ID: wpr-155577

ABSTRACT

Getah virus (GETV), which is transmitted by mosquitoes, causes lower limb edema and stiffness in horses. In this study, we investigated the sero-surveillance of GETV among Thoroughbred racehorses in Korea during 2013 and 2014. A total of 1,182 equine serum samples collected from Thoroughbred racehorses in four provinces (Gyeongnam, Gyeonggi, Jeonbuk and Jeju provinces) were analyzed using virus neutralization (VN) tests. An antibody titer of > or = 1:2 was considered positive. Overall, the seropositivity rate for GETV was found to be 12.4% (146/1,182) among the racehorses; the annual seropositivity rates were 12.4% and 12.2% in 2013 and 2014, respectively. The seropositivity rates in April and September in 2013 turned out to be 8.6% and 15.2%, respectively. The regional distribution of seropositivity ranged from 5.0% to 22.3% in 2013 and from 0.0% to 15.0% in 2014, respectively. Gyeongnam province had the highest seropositivity rate than other provinces. By analyzing the distribution of VN titers according to horse age, we found that the highest GETV seropositivity rate was in horses over 6 years of age (22.4% and 28.1%, 2013 and 2014, respectively), and that the incidence of GETV was higher in geldings (17.6% and 18.6%, 2013 and 2014, respectively) than in males and females. These results indicate that Thoroughbred horses raised in Korea were bitten by mosquitoes harboring GETV.


Subject(s)
Alphavirus , Culicidae , Edema , Female , Horses , Humans , Incidence , Korea , Lower Extremity , Male
20.
Article in English | WPRIM | ID: wpr-218814

ABSTRACT

Three QIAG93 strains, QIAG9301, QIAG9302 and QIAG9303 that have been identified as Getah virus (GETV) are analyzed in this study. The morphological features of three virus isolates were observed by using electron microscopy, suggesting that the QIAG9301, QIAG9302 and QIAG9303 isolate can be classified as tentative member of Alphavirus species in the Semliki Forest complex. The full length of the structural polyprotein gene of each QIAG93 isolate (QIAG9301, QIAG9302 and QIAG9303) was determined that are identical in size, comprising 3759 nucleotides that encoded 1253 amino acids. The sequence analysis of the structural polyprotein gene, including the C, E3, E1, 6K and E2 domain, showed that each QIAG93 isolate shares >98.9% sequence identity. The phylogenetic analysis and evolutionary distance (ED) estimation based on the structural polyprotein gene sequence showed that the QIAG9301 isolate is closely related to GETV South Korea strain (99.9% sequence identity and ED value 0.001) and Chinese GETV YN0540 strain (99.3% sequence identity ED value 0.007) than other Alphavirus species analyzed in this study. Both QIAG9032 and QIAG9303 isolate exhibited genetically close relationship with Mongolian GETV LEIV17741MPR strain (at least 99.3% sequence identity and mean ED value 0.0065). Therefore, our findings will be valuable for molecular epidemiological analyses of GETV in Korea and contribute to a further study on pathogenicity of three QIAG93 isolates in animals.


Subject(s)
Alphavirus , Amino Acids , Animals , Asians , Humans , Korea , Microscopy, Electron , Molecular Epidemiology , Nucleotides , Sequence Analysis , Trees , Virulence
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