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1.
Viruses ; 14(2)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35215895

RESUMO

The emergence of new SARS-CoV-2 variants represents a constant threat to world public health. The SARS-CoV-2 Delta variant was identified in late 2020 in India; since then, it has spread to many other countries, replacing other predominant lineages and raising concerns about vaccination efficiency. We evaluated the sensitivity of the Delta variant to antibodies elicited by COVID-19 vaccinated (CoronaVac and ChAdOx1) and convalescent individuals previously infected by earlier lineages and by the Gamma variant. No reduction in the neutralizing efficacy of the Delta variant was observed when compared to B lineage and a reduced neutralization was observed for the Gamma variant. Our results indicate that neutralization of the Delta variant is not compromised in individuals vaccinated by CoronaVac or ChAdOx1; however, a reduction in neutralization efficacy is expected for individuals infected by the Gamma variant, highlighting the importance of continuous vaccination even for previously infected individuals.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , ChAdOx1 nCoV-19/imunologia , SARS-CoV-2/imunologia , Adulto , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/classificação , ChAdOx1 nCoV-19/administração & dosagem , Convalescença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , SARS-CoV-2/genética , Vacinação
2.
Arch Virol ; 167(1): 183-187, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34727217

RESUMO

Viral stability under stress conditions may directly affect viral dissemination, seasonality, and pathogenesis. We exposed airborne viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), mumps virus, coxsackievirus B5, human rhinovirus A16, and respiratory syncytial virus, to different temperatures, UV light exposure time, pH values, and osmotic pressures and measured the remaining viral infectivity. Reduced thermal stability was observed for coxsackievirus B5 at 45 °C, while SARS-CoV-2 demonstrated residual infectivity at 55 °C. UV light exposure was an efficient means of viral inactivation but was less efficient for non-enveloped viruses. Rhinovirus A16 and respiratory syncytial virus demonstrated extreme sensitivity to acid conditions, while SARS-CoV-2, rhinovirus A16, and respiratory syncytial virus were unstable in an alkaline environment. The information obtained in this study will be useful for the development of viral inactivation methods and may be correlated with epidemiological and seasonal viral characteristics.


Assuntos
COVID-19 , Viroses , Vírus , Humanos , SARS-CoV-2 , Inativação de Vírus
3.
J Virol ; 95(23): e0112221, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34549980

RESUMO

Chikungunya virus (CHIKV) and Mayaro virus (MAYV) are closely related members of the Semliki Forest virus antigenic complex classified as belonging to the genus Alphavirus of the family Togaviridae. These viruses cause human disease, with sudden fever and joint inflammation that can persist for long periods. CHIKV is the causative agent of large outbreaks worldwide, and MAYV infection represents a growing public health concern in Latin America, causing sporadic cases and geographically limited outbreaks. Considering the relationship between CHIKV and MAYV, the present study aimed to evaluate if preexisting CHIKV immunity protects against MAYV infection. Immunocompetent C57BL/6 mice were intraperitoneally infected with CHIKV and, 4 weeks later, they were infected with MAYV in their hind paw. We observed that the preexistence of CHIKV immunity conferred partial cross-protection against secondary MAYV infection, reducing disease severity, tissue viral load, and histopathological scores. Interestingly, CHIKV antibodies from humans and mice showed low cross-neutralization to MAYV, but neutralizing activity significantly increased after secondary infection. Furthermore, depletion of adaptive immune cells (CD4+ T, CD8+ T, and CD19+ B cells) did not alter the cross-protection phenotype, suggesting that distinct cell subsets or a combination of adaptive immune cells stimulated by CHIKV are responsible for the partial cross-protection against MAYV. The reduction of proinflammatory cytokines, such as interferon gamma (IFN-γ), in animals secondarily infected by MAYV, suggests a role for innate immunity in cross-protection. Our findings shed light on how preexisting immunity to arthritogenic alphaviruses may affect secondary infection, which may further develop relevant influence in disease outcome and viral transmission. IMPORTANCE Mosquito-borne viruses have a worldwide impact, especially in tropical climates. Chikungunya virus has been present mostly in developing countries, causing millions of infections, while Mayaro virus, a close relative, has been limited to the Caribbean and tropical regions of Latin America. The potential emergence and spread of Mayaro virus to other high-risk areas have increased the scientific community's attention to an imminent worldwide epidemic. Here, we designed an experimental protocol of chikungunya and Mayaro virus mouse infection, which develops a measurable and quantifiable disease that allows us to make inferences about potential immunological effects during secondary virus infection. Our results demonstrate that previous chikungunya virus infection is able to reduce the severity of clinical outcomes during secondary Mayaro infection. We provide scientific understanding of immunological features during secondary infection with the closely related virus, thus assisting in better comprehending viral transmission and the pathological outcome of these diseases.


Assuntos
Infecções por Alphavirus/imunologia , Infecções por Alphavirus/prevenção & controle , Vírus Chikungunya/imunologia , Proteção Cruzada/imunologia , Alphavirus/imunologia , Infecções por Alphavirus/patologia , Animais , Anticorpos Antivirais/imunologia , Febre de Chikungunya/virologia , Modelos Animais de Doenças , Epidemias , Feminino , Inflamação , Camundongos , Camundongos Endogâmicos C57BL , Carga Viral
4.
Infect Genet Evol ; 95: 105041, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34411742

RESUMO

Paramyxoviruses have a broad host range and geographic distribution, including human pathogens transmitted by bats, such as Nipah and Hendra viruses. In this study, we combined high-throughput sequencing and molecular approaches to investigate the presence of paramyxoviruses in neotropical bats (Microchiroptera suborder) in Brazil. We discovered and characterized three novel paramyxoviruses in the kidney tissues of apparently healthy common vampire bats (D. rotundus) and Seba's short-tailed bats (C. perspicillata), which we tentatively named Kanhgág virus (KANV), Boe virus (BOEV), and Guató virus (GUATV). In this study, we classified these viruses as putative species into the Macrojêvirus genus, a newly proposed genus of the Orthoparamyxovirinae subfamily. Using RT-PCR, we detected these viruses in 20.9% (9 out of 43) of bats tested, and viral RNA was detected exclusively in kidney tissues. Attempts to isolate infectious virus were successful for KANV and GUATV. Our results expand the viral diversity, host range, and geographical distribution of the paramyxoviruses.


Assuntos
Quirópteros , Infecções por Paramyxoviridae/veterinária , Paramyxoviridae/classificação , Animais , Brasil/epidemiologia , Especificidade de Hospedeiro , Paramyxoviridae/fisiologia , Filogenia , Prevalência , RNA Viral/análise
5.
Sci Data ; 8(1): 73, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33664243

RESUMO

Brazil has one of the fastest-growing COVID-19 epidemics worldwide. Non-pharmaceutical interventions (NPIs) have been adopted at the municipal level with asynchronous actions taken across 5,568 municipalities and the Federal District. This paper systematises the fragmented information on NPIs reporting on a novel dataset with survey responses from 4,027 mayors, covering 72.3% of all municipalities in the country. This dataset responds to the urgency to track and share findings on fragmented policies during the COVID-19 pandemic. Quantifying NPIs can help to assess the role of interventions in reducing transmission. We offer spatial and temporal details for a range of measures aimed at implementing social distancing and the dates when these measures were relaxed by local governments.


Assuntos
COVID-19/prevenção & controle , Controle de Doenças Transmissíveis/métodos , Brasil , COVID-19/transmissão , Cidades , Humanos , Pandemias
6.
Clin Infect Dis ; 73(7): e2436-e2443, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32766829

RESUMO

BACKGROUND: Chikungunya virus (CHIKV) emerged in the Americas in 2013 and has caused approximately 2.1 million cases and >600 deaths. A retrospective investigation was undertaken to describe clinical, epidemiological, and viral genomic features associated with deaths caused by CHIKV in Ceará state, northeast Brazil. METHODS: Sera, cerebrospinal fluid (CSF), and tissue samples from 100 fatal cases with suspected arbovirus infection were tested for CHIKV, dengue virus (DENV), and Zika virus (ZIKV). Clinical, epidemiological, and death reports were obtained for patients with confirmed CHIKV infection. Logistic regression analysis was undertaken to identify independent factors associated with risk of death during CHIKV infection. Phylogenetic analysis was conducted using whole genomes from a subset of cases. RESULTS: Sixty-eight fatal cases had CHIKV infection confirmed by reverse-transcription quantitative polymerase chain reaction (52.9%), viral antigen (41.1%), and/or specific immunoglobulin M (63.2%). Co-detection of CHIKV with DENV was found in 22% of fatal cases, ZIKV in 2.9%, and DENV and ZIKV in 1.5%. A total of 39 CHIKV deaths presented with neurological signs and symptoms, and CHIKV-RNA was found in the CSF of 92.3% of these patients. Fatal outcomes were associated with irreversible multiple organ dysfunction syndrome. Patients with diabetes appear to die at a higher frequency during the subacute phase. Genetic analysis showed circulation of 2 CHIKV East-Central-South African (ECSA) lineages in Ceará and revealed no unique virus genomic mutation associated with fatal outcome. CONCLUSIONS: The investigation of the largest cross-sectional cohort of CHIKV deaths to date reveals that CHIKV-ECSA strains can cause death in individuals from both risk and nonrisk groups, including young adults.


Assuntos
Febre de Chikungunya , Vírus da Dengue , Dengue , Infecção por Zika virus , Zika virus , Brasil/epidemiologia , Febre de Chikungunya/epidemiologia , Estudos Transversais , Humanos , Filogenia , Estudos Retrospectivos , Adulto Jovem , Zika virus/genética , Infecção por Zika virus/epidemiologia
7.
Nat Hum Behav ; 4(8): 856-865, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32737472

RESUMO

The first case of COVID-19 was detected in Brazil on 25 February 2020. We report and contextualize epidemiological, demographic and clinical findings for COVID-19 cases during the first 3 months of the epidemic. By 31 May 2020, 514,200 COVID-19 cases, including 29,314 deaths, had been reported in 75.3% (4,196 of 5,570) of municipalities across all five administrative regions of Brazil. The R0 value for Brazil was estimated at 3.1 (95% Bayesian credible interval = 2.4-5.5), with a higher median but overlapping credible intervals compared with some other seriously affected countries. A positive association between higher per-capita income and COVID-19 diagnosis was identified. Furthermore, the severe acute respiratory infection cases with unknown aetiology were associated with lower per-capita income. Co-circulation of six respiratory viruses was detected but at very low levels. These findings provide a comprehensive description of the ongoing COVID-19 epidemic in Brazil and may help to guide subsequent measures to control virus transmission.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus , Transmissão de Doença Infecciosa , Influenza Humana , Pandemias , Pneumonia Viral , Adulto , Idoso , Brasil/epidemiologia , COVID-19 , Teste para COVID-19 , Criança , Técnicas de Laboratório Clínico/métodos , Técnicas de Laboratório Clínico/estatística & dados numéricos , Coinfecção/epidemiologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/terapia , Infecções por Coronavirus/transmissão , Transmissão de Doença Infecciosa/prevenção & controle , Transmissão de Doença Infecciosa/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Influenza Humana/virologia , Masculino , Mortalidade , Pneumonia Viral/diagnóstico , Pneumonia Viral/mortalidade , Pneumonia Viral/terapia , Pneumonia Viral/transmissão , SARS-CoV-2 , Fatores Socioeconômicos , Tratamento Farmacológico da COVID-19
8.
Infect Genet Evol ; 75: 104036, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31499226

RESUMO

The Dicistroviridae family comprises positive single-stranded RNA viruses that are classified into Picornavirales order. These viruses are identified in arthropod hosts, including some having devastating economic consequences. Here, we described and characterized a novel nearly complete dicistrovirus genome identified in liver samples of velvety free-tailed bats (Molossus molossus) collected in June 2010 in Araçatuba city, São Paulo State, Brazil. This novel virus presents a genome of 9262 nucleotides in length and a typical dicistrovirus genome organization. Based on our phylogenetic analysis and ICTV criteria, we propose this virus as a novel species into the Triatovirus genus. Attempts of viral propagation in Vero E6 and C6/36 cell lines were unsuccessful. The novel dicistrovirus was detected only in one out of nine liver bat samples, representing for the first time an internal organ detection from a representative of this virus family.


Assuntos
Quirópteros/virologia , Dicistroviridae/classificação , Dicistroviridae/genética , Animais , Brasil , Biologia Computacional/métodos , Genoma Viral , Filogenia , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
9.
Sci Rep ; 9(1): 5556, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30944402

RESUMO

Birds are the natural reservoir of viruses with zoonotic potential, as well as contributing to the evolution, emergence, and dissemination of novel viruses. In this study, we applied a high-throughput screening approach to identify the diversity of viruses in 118 samples of birds captured between October 2006 to October 2010 in the North and Northeast regions of Brazil. We found nearly complete genomes of novel species of astrovirus and calicivirus in cloacal swabs of ruddy turnstones (Arenaria interpres) collected in Coroa do Avião islet, Pernambuco State. These viruses are positive-sense single-stranded RNA with a genome of ~7 to 8 kb, and were designated as Ruddy turnstone astrovirus (RtAstV) and Ruddy turnstone calicivirus (RTCV), respectively. Phylogenetic analysis showed that RtAstV and RTCV grouped in a monophyletic clade with viruses identified from poultry samples (i.e., chicken, goose, and turkey), including viruses associated with acute nephritis in chickens. Attempts of viral propagation in monkey and chicken cell lines for both viruses were unsuccessful. Also, we found genomes related with viral families that infect invertebrates and plants, suggesting that they might be ingested in the birds' diet. In sum, these findings shed new light on the diversity of viruses in migratory birds with the notable characterization of a novel astrovirus and calicivirus.


Assuntos
Astroviridae/genética , Doenças das Aves/virologia , Caliciviridae/genética , Charadriiformes/virologia , Migração Animal , Animais , Astroviridae/isolamento & purificação , Infecções por Astroviridae/veterinária , Brasil , Caliciviridae/isolamento & purificação , Infecções por Caliciviridae/veterinária , Galinhas/virologia , Chlorocebus aethiops , Cloaca/virologia , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Metagenoma , Filogenia , Células Vero
10.
J Med Virol ; 91(7): 1250-1262, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30815882

RESUMO

The role of human adenovirus (HAdV) infection in different acute diseases, such as febrile exudative tonsillitis, conjunctivitis, and pharyngoconjunctival fever is well established. However, the relationships, if any, of HAdV persistence and reactivation in the development of the chronic adenotonsillar disease is not fully understood. The present paper reports a 3-year cross-sectional hospital-based study aimed at detecting and quantifying HAdV DNA and mRNA of the HAdV hexon gene in adenoid and palatine tonsil tissues and nasopharyngeal secretions (NPS) from patients with adenotonsillar hypertrophy or recurrent adenotonsillitis. HAdV C, B, and E were detectable in nearly 50% of the patients, with no association with the severity of airway obstruction, nor with the presence of recurrent tonsillitis, sleep apnea or otitis media with effusion (OME). Despite the higher rates of respiratory viral coinfections in patients with HAdV, the presence of other viruses, including DNA and RNA viruses, had no association with HAdV replication or shedding in secretions. Higher HAdV loads in adenoids showed a significant positive correlation with the presence of sleep apnea and the absence of OME. Although this study indicates that a significant proportion (~85%) of individuals with chronic adenotonsillar diseases have persistent nonproductive HAdV infection, including those by HAdV C, B, and E, epithelial and subepithelial cells in tonsils seem to be critical for HAdV C production and shedding in NPS in some patients, since viral antigen was detected in these regions by immunohistochemistry in four patients, all of which were also positive for HAdV mRNA detection.


Assuntos
Tonsila Faríngea/virologia , Infecções por Adenovirus Humanos/virologia , Tonsila Palatina/virologia , Replicação Viral , Tonsila Faríngea/patologia , Infecções por Adenovirus Humanos/diagnóstico , Adenovírus Humanos/classificação , Adenovírus Humanos/isolamento & purificação , Adenovírus Humanos/fisiologia , Adolescente , Criança , Pré-Escolar , Estudos Transversais , DNA Viral/isolamento & purificação , Feminino , Humanos , Hipertrofia , Lactente , Masculino , Tonsila Palatina/patologia , Tonsilite/virologia
11.
Viruses ; 11(3)2019 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-30909631

RESUMO

The Hepacivirus genus comprises single-stranded positive-sense RNA viruses within the family Flaviviridae. Several hepaciviruses have been identified in different mammals, including multiple rodent species in Africa, Asia, Europe, and North America. To date, no rodent hepacivirus has been identified in the South American continent. Here, we describe an unknown hepacivirus discovered during a metagenomic screen in Akodon montensis, Calomys tener, Oligoryzomys nigripes, Necromys lasiurus, and Mus musculus from São Paulo State, Brazil. Molecular detection of this novel hepacivirus by RT-PCR showed a frequency of 11.11% (2/18) in Oligoryzomys nigripes. This is the first identification of hepavivirus in sigmondonine rodents and in rodents from South America. In sum, our results expand the host range, viral diversity, and geographical distribution of the Hepacivirus genus.


Assuntos
Reservatórios de Doenças/virologia , Genoma Viral , Hepacivirus/classificação , Hepacivirus/isolamento & purificação , Sigmodontinae/virologia , Animais , Especificidade de Hospedeiro , Filogenia , RNA Viral/genética , América do Sul
12.
J Clin Microbiol ; 57(5)2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30787146

RESUMO

Mayaro virus (MAYV) is a neglected arthropod-borne virus (arbovirus) antigenically clustered into the Semliki Forest complex group of Alphavirus genus (Togaviridae family), maintained in an unclear zoonotic cycle involving mosquitoes from Haemagogus genus as the main vector. The genome is composed of a positive single-stranded RNA of 11.5 kb in length, which contains two genes that encode four nonstructural (nsP1 to nsP4) and five structural (C, E3, E2, 6K, and E1) proteins. In the present study, we have developed an enzyme-linked immunosorbent assay (ELISA) using as antigen the recombinant envelope protein 2 of MAYV produced in an Escherichia coli system (rE2-MAYV ELISAs). A panel of 68 human serum samples from suspected arboviral cases was analyzed and titrated for anti-MAYV IgM and IgG antibody detection. The rE2-MAYV ELISA detected 33.8% (23/68) IgG-positive samples, demonstrating 100% sensitivity and 78.95% specificity compared to the MAYV-specific 50% plaque reduction neutralization assay. In addition, the positive MAYV-neutralizing samples showed high titers of detection by rE2-MAYV ELISA, suggesting a highly sensitive test. The rE2-MAYV ELISA also detected 42.5% (29/68) IgM-positive samples, of which 13.8% (4/29) presented high-avidity interactions with rE2-MAYV. Cross-reactivity was observed with Chikungunya virus (CHIKV)-specific murine antibody sample but not with CHIKV-specific human and other Alphavirus murine antibodies. In short, we have developed a rapid, simple, specific, and sensitive MAYV rE2-ELISA, and our preliminary results show its potential applicability to diagnosis of MAYV infections.


Assuntos
Infecções por Alphavirus/imunologia , Alphavirus/imunologia , Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Proteínas do Envelope Viral/imunologia , Animais , Afinidade de Anticorpos , Vírus Chikungunya/imunologia , Reações Cruzadas , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Testes Sorológicos , Proteínas do Envelope Viral/genética
13.
Infect Genet Evol ; 68: 16-22, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30504003

RESUMO

Oropouche orthobunyavirus (OROV) has significant impact in public health in Amazon region. This arbovirus is one of the most common causes of febrile illness in Brazil, and is responsible for several epidemics since 1960's. In this study, we sequenced and characterized the complete coding sequences (S-, M- and L-RNA) of 35 OROV isolates from Brazil. Here, we classified 20 strains in genotype I from Pará and Maranhão states, nine as genotype II from Pará and Rondônia states confirmed, four classified into genotype III from Acre, Maranhão, Minas Gerais and Rondônia states and two genotype IV from Amazonas State. Also, we did not observe reassortment events involving the OROV isolates. In addition, we developed novel RT-PCR tools to identify reassortment events among OROV strains. These data will be useful to better understand the molecular epidemiology and diagnostic of OROV infections.


Assuntos
Infecções por Bunyaviridae/virologia , Genoma Viral , Genômica , Orthobunyavirus/genética , Vírus Reordenados/genética , Animais , Brasil/epidemiologia , Chlorocebus aethiops , Biologia Computacional/métodos , Genômica/métodos , Genótipo , Geografia Médica , Humanos , Epidemiologia Molecular , Anotação de Sequência Molecular , Tipagem Molecular , Orthobunyavirus/classificação , Filogenia , Células Vero
14.
Ecohealth ; 15(3): 577-589, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30105563

RESUMO

New World orthohantaviruses are emerging RNA viruses that cause hantavirus cardiopulmonary syndrome (HCPS). These viruses are a burden to public health around the world with a lethality rate of around 60%. In South America, rodents of Sigmodontinae subfamily are the main reservoirs of orthohantaviruses. We described a serosurvey for orthohantaviruses circulation in an apparently healthy human population and small mammals from rural areas in Central Minas Gerais State, Brazil. A total of 240 individuals and 50 small mammals (26 rodents belonging to 10 different species and 24 marsupials from 4 different species) were sampled during 2012-2013. The seroprevalence rates of IgG/IgM antibodies in humans were 7.1 and 1.6%, respectively. Only one rodent, an Oligoryzomys nigripes captured in peridomestic area, tested positive for IgG antibodies and viral RNA. Our findings suggest a silent circulation of orthohantaviruses in a region of intensive agriculture production. The detection of seropositive humans in an area with a lack of previous HCPS reports highlights potential oligosymptomatic cases and the need for surveillance strategies that could reduce the risk of future outbreaks.


Assuntos
Reservatórios de Doenças/virologia , Infecções por Hantavirus/transmissão , Mamíferos/virologia , Orthohepadnavirus/isolamento & purificação , Roedores/virologia , Animais , Brasil/epidemiologia , Infecções por Hantavirus/epidemiologia , Humanos , Estudos Soroepidemiológicos
15.
Virol J ; 15(1): 112, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-30041676

RESUMO

BACKGROUND: Chikungunya (CHIKV) virus is an important mosquito-borne virus causing outbreaks of acute febrile illness with arthropathy. The detection of specific antibodies against CHIKV is used for diagnosis after the acute viremic phase of the disease. However, a major challenge for serologic diagnosis of CHIKV and other alphaviruses is the cross-reactivity of antibodies to common antigens among these viruses. In the present study, we have developed an enzyme-linked immunosorbend assay using a recombinant envelope protein 2 of CHIKV produced in Escherichia coli system, as a capture antigen. RESULTS: High titers (1600 to 12,800) of anti-CHIKV antibodies were detected in human sera analyzed by the CHIKV assay, suggesting it may detect low levels of the antibodies presence. On the other side, cross-reactivity was not observed in mouse hyperimmune sera to Mayaro virus and other alphaviruses analyzed by the CHIKV immunosorbend assay, suggesting it is a CHIKV-specific test. Fifty-nine human serum samples of CHIKV infection suspected cases were tested for immunoglobulin G (IgG) and M (IgM) antibodies detection using the CHIKV immunosorbend assay. A total of 44% (26/59) of samples were positive for IgG to CHIKV, determining 89.66% sensitivity and 100% specificity when the assay is compared to a CHIKV-specific neutralization assay. In addition, 40.6% (24/59) of samples were positive for IgM, determining 92.48% sensitivity and 79.04% specificity by a Bayesian method in the absence of a gold standard. Moreover, CHIKV immunosorbend assay showed similar sensibilities to a commercial immunochromatography assay (Lumiquick, USA) for CHIKV IgG and IgM detection. CONCLUSION: In short, we have developed a rapid, simple, specific and sensitive CHIKV immunosorbend assay for IgG and IgM detection and our results showed potential applicability on the diagnosis of infections by this virus.


Assuntos
Antígenos Virais/imunologia , Febre de Chikungunya/diagnóstico , Febre de Chikungunya/imunologia , Vírus Chikungunya/imunologia , Ensaio de Imunoadsorção Enzimática , Proteínas do Envelope Viral/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Testes de Neutralização , Proteínas Recombinantes , Sensibilidade e Especificidade
16.
Arch Virol ; 163(10): 2913-2915, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29931397

RESUMO

The nearly complete genome sequence of a novel polyomavirus from blood samples of Akodon montensis and Calomys tener collected in Brazil was determined by high-throughput sequencing. This virus showed a typical polyomaviruses genome organization, and it was classified as a member of the genus Betapolyomavirus. Our results expand the host range and viral diversity of the family Polyomaviridae.


Assuntos
Antígenos Virais de Tumores/genética , Genoma Viral/genética , Polyomaviridae , Sigmodontinae/virologia , Sequência de Aminoácidos/genética , Animais , Brasil , Especificidade de Hospedeiro , Filogenia , Polyomaviridae/classificação , Polyomaviridae/genética , Polyomaviridae/isolamento & purificação
17.
PLoS One ; 13(5): e0197294, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29795585

RESUMO

Group C serogroup includes members of the Orthobunyavirus genus (family Peribunyaviridae) and comprises 15 arboviruses that can be associated with febrile illness in humans. Although previous studies described the genome characterization of Group C orthobunyavirus, there is a gap in genomic information about the other viruses in this group. Therefore, in this study, complete genomes of members of Group C serogroup were sequenced or re-sequenced and used for genetic characterization, as well as to understand their phylogenetic and evolutionary aspects. Thus, our study reported the genomes of three new members in Group C virus (Apeu strain BeAn848, Itaqui strain BeAn12797 and Nepuyo strain BeAn10709), as well as re-sequencing of original strains of five members: Caraparu (strain BeAn3994), Madrid (strain BT4075), Murucutu (strain BeAn974), Oriboca (strain BeAn17), and Marituba (strain BeAn15). These viruses presented a typical genomic organization related to members of the Orthobunyavirus genus. Interestingly, all viruses of this serogroup showed an open reading frame (ORF) that encodes the putative nonstructural NSs protein that precedes the nucleoprotein ORF, an unprecedented fact in Group C virus. Also, we confirmed the presence of natural reassortment events. This study expands the genomic information of Group C viruses, as well as revalidates the genomic organization of viruses that were previously reported.


Assuntos
Orthobunyavirus/genética , Animais , Brasil , Chlorocebus aethiops , Evolução Molecular , Genoma Viral , Humanos , Orthobunyavirus/isolamento & purificação , Filogenia , Células Vero
18.
Virology ; 519: 12-16, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29627586

RESUMO

The Hepeviridae comprise single-stranded positive-sense RNA viruses classified into two genera, Orthohepevirus and Piscihepevirus. Orthohepeviruses have a wide host range that includes rodents, but previous studies had been restricted to rodents of the Muridae family. In this study, we applied a high-throughput sequencing approach to examine the presence of orthohepeviruses in rodents from São Paulo State, Brazil. We also used RT-PCR to determine the frequency of orthohepeviruses in our sampled population. We identified novel orthohepeviruses in blood samples derived from Necromys lasiurus (1.19%) and Calomys tener (3.66%). Therefore, our results expand the host range and viral diversity of the Hepeviridae family.


Assuntos
Animais Selvagens/virologia , Infecções por Vírus de RNA/veterinária , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , Doenças dos Roedores/epidemiologia , Roedores/virologia , Animais , Brasil/epidemiologia , Quirópteros/virologia , Reservatórios de Doenças , Sequenciamento de Nucleotídeos em Larga Escala , Especificidade de Hospedeiro , Filogenia , Infecções por Vírus de RNA/epidemiologia , Infecções por Vírus de RNA/virologia , Vírus de RNA/classificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sorogrupo
19.
Viruses ; 10(4)2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29565808

RESUMO

Parvoviruses (family Parvoviridae) are small, single-stranded DNA viruses. Many parvoviral pathogens of medical, veterinary and ecological importance have been identified. In this study, we used high-throughput sequencing (HTS) to investigate the diversity of parvoviruses infecting wild and domestic animals in Brazil. We identified 21 parvovirus sequences (including twelve nearly complete genomes and nine partial genomes) in samples derived from rodents, bats, opossums, birds and cattle in Pernambuco, São Paulo, Paraná and Rio Grande do Sul states. These sequences were investigated using phylogenetic and distance-based approaches and were thereby classified into eight parvovirus species (six of which have not been described previously), representing six distinct genera in the subfamily Parvovirinae. Our findings extend the known biogeographic range of previously characterized parvovirus species and the known host range of three parvovirus genera (Dependovirus, Aveparvovirus and Tetraparvovirus). Moreover, our investigation provides a window into the ecological dynamics of parvovirus infections in vertebrates, revealing that many parvovirus genera contain well-defined sub-lineages that circulate widely throughout the world within particular taxonomic groups of hosts.


Assuntos
Doenças dos Animais/epidemiologia , Doenças dos Animais/virologia , Animais Domésticos , Animais Selvagens , Infecções por Parvoviridae/veterinária , Parvovirus/classificação , Animais , Biodiversidade , Brasil/epidemiologia , Genoma Viral , Genômica/métodos , Geografia Médica , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Vigilância em Saúde Pública , Zoonoses
20.
Infect Genet Evol ; 60: 71-76, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29476812

RESUMO

Tacaiuma virus (TCMV) is antigenically characterized as a member of the Anopheles A complex in the Orthobunyavirus genus, Peribunyaviridae family (Bunyavirales order). Clinically, the TCMV infection is characterized by acute febrile illness with myalgia and arthralgia lasting three to five days. However, the genomic and evolutionary aspect of this virus has not been elucidated. In this study, we described the complete coding sequences of three segments of two TCMV strains isolated in Brazil and three complete coding sequences of the small segment of three TCMV strains. All the strains sequenced in this study showed the typical genomic organization of orthobunyaviruses that infect vertebrates, except for the absence of the open reading frame that encodes the well-described non-structural small protein. This study presents the genomic and evolutionary characterization of TCMV strains and would be helpful for diagnostic purposes and epidemiology.


Assuntos
Orthobunyavirus/classificação , Orthobunyavirus/genética , Animais , Brasil , Infecções por Bunyaviridae/virologia , Chlorocebus aethiops , Evolução Molecular , Genoma Viral/genética , Humanos , Filogenia , RNA Viral/análise , RNA Viral/genética , Células Vero
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