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1.
Cad Saude Publica ; 40(3): e00076723, 2024.
Artigo em Português | MEDLINE | ID: mdl-38536977

RESUMO

Air temperature is a climatic factor that affects the incidence of dengue, with effects varying according to time and space. We investigated the relationship between minimum air temperature and dengue incidence in Minas Gerais, Brazil, and evaluated the influence of socioeconomic and geographic variables on this relationship. This is a time series study with analysis conducted in three distinct stages: modeling using a distributed lag non-linear model, meta-analysis of models obtained, and meta-regression with geographic and socioeconomic data. Minimum temperature was a protective factor at extreme cold temperatures (RR = 0.65; 95%CI: 0.56-0.76) and moderate cold temperatures (RR = 0.71; 95%CI: 0.64-0.79), and a risk factor at moderate hot temperatures (RR = 1.15; 95%CI: 1.07-1.24), but not at extreme hot temperatures (RR = 1.1; 95%CI: 0.99-1.22). Heterogeneity of the models was high (I2 = 60%), which was also observed in meta-regression. Moderate and extreme cold temperatures have a protective effect, while moderate hot temperatures increase the risk. However, minimum air temperature does not explain the variability in the region, not even with the other variables in meta-regression.


A temperatura do ar é um fator climático que afeta a incidência da dengue, com efeitos variando conforme o tempo e o espaço. Investigamos a relação entre a temperatura mínima do ar e a incidência da doença em Minas Gerais, Brasil, e avaliamos a influência de variáveis socioeconômicas e geográficas nessa relação, calculando-se o risco relativo (RR). Este é um estudo de série temporal com análise conduzida em três etapas distintas: modelagem por uso de distributed lag non-linear model (modelos não-lineares distributivos com defasagem), metanálise dos modelos obtidos e metarregressão com dados geográficos e socioeconômicos. A temperatura mínima foi um fator de proteção quando em temperaturas frias extremas (RR = 0,65; IC95%: 0,56-0,76) e moderadas (RR = 0,71; IC95%: 0,64-0,79) e fator de risco em temperaturas de calor moderado (RR = 1,15; IC95%: 1,07-1,24), mas não em extremo (RR = 1,1; IC95%: 0,99-1,22). A heterogeneidade dos modelos foi elevada (I2 = 60%) e essa medida não foi alterada em metarregressão. Temperaturas frias moderadas e extremas causam efeito protetivo, enquanto moderadas quentes aumentam o risco. No entanto, a temperatura mínima do ar não explica nem a variabilidade da região, nem mesmo com as outras variáveis em metarregressão.


La temperatura del aire es un factor climático que afecta la incidencia del dengue, con efectos que varían según el tiempo y el territorio. Investigamos la relación entre la temperatura mínima del aire y la incidencia de la enfermedad en Minas Gerais, Brasil, y evaluamos la influencia de variables socioeconómicas y geográficas en esta relación. Se trata de un estudio de serie temporal cuyo análisis se realiza en tres etapas distintas: modelación mediante el uso de distributed lag non-linear model (modelos distributivos no lineales con retraso), metaanálisis de los modelos obtenidos y metarregresión con datos geográficos y socioeconómicos. La temperatura mínima fue un factor de protección ante temperaturas extremadamente frías (RR = 0,65; IC95%: 0,56-0,76) y moderadas (RR = 0,71; IC95%: 0,64-0,79) y factor de riesgo en temperaturas de calor moderado (RR = 1,15; IC95%: 1,07-1,24), pero no en extremo (RR = 1,1; IC95%: 0,99-1,22). La heterogeneidad de los modelos fue alta (I2 = 60%), y esta medida no se modificó en la metarregresión. Las temperaturas frías moderadas y extremas tienen un efecto protector, mientras que las temperaturas moderadamente altas aumentan el riesgo. Sin embargo, la temperatura mínima del aire no explica la variabilidad de la región, ni siquiera con las demás variables en metarregresión.


Assuntos
Temperatura Baixa , Dengue , Humanos , Temperatura , Brasil/epidemiologia , Fatores de Tempo , Temperatura Alta , Dengue/epidemiologia
2.
PLoS Negl Trop Dis ; 18(3): e0012013, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38484018

RESUMO

BACKGROUND: Chikungunya virus (CHIKV) has spread across Brazil with varying incidence rates depending on the affected areas. Due to cocirculation of arboviruses and overlapping disease symptoms, CHIKV infection may be underdiagnosed. To understand the lack of CHIKV epidemics in São José do Rio Preto (SJdRP), São Paulo (SP), Brazil, we evaluated viral circulation by investigating anti-CHIKV IgG seroconversion in a prospective study of asymptomatic individuals and detecting anti-CHIKV IgM in individuals suspected of dengue infection, as well as CHIKV presence in Aedes mosquitoes. The opportunity to assess two different groups (symptomatic and asymptomatic) exposed at the same geographic region aimed to broaden the possibility of identifying the viral circulation, which had been previously considered absent. METHODOLOGY/PRINCIPAL FINDINGS: Based on a prospective population study model and demographic characteristics (sex and age), we analyzed the anti-CHIKV IgG seroconversion rate in 341 subjects by ELISA over four years. The seroprevalence increased from 0.35% in the first year to 2.3% after 3 years of follow-up. Additionally, we investigated 497 samples from a blood panel collected from dengue-suspected individuals during the 2019 dengue outbreak in SJdRP. In total, 4.4% were positive for anti-CHIKV IgM, and 8.6% were positive for IgG. To exclude alphavirus cross-reactivity, we evaluated the presence of anti-Mayaro virus (MAYV) IgG by ELISA, and the positivity rate was 0.3% in the population study and 0.8% in the blood panel samples. In CHIKV and MAYV plaque reduction neutralization tests (PRNTs), the positivity rate for CHIKV-neutralizing antibodies in these ELISA-positive samples was 46.7%, while no MAYV-neutralizing antibodies were detected. Genomic sequencing and phylogenetic analysis revealed CHIKV genotype ECSA in São José do Rio Preto, SP. Finally, mosquitoes collected to complement human surveillance revealed CHIKV positivity of 2.76% of A. aegypti and 9.09% of A. albopictus (although it was far less abundant than A. aegypti) by RT-qPCR. CONCLUSIONS/SIGNIFICANCE: Our data suggest cryptic CHIKV circulation in SJdRP detected by continual active surveillance. These low levels, but increasing, of viral circulation highlight the possibility of CHIKV outbreaks, as there is a large naïve population. Improved knowledge of the epidemiological situation might aid in outbreaks prevention.


Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Dengue , Animais , Humanos , Vírus Chikungunya/genética , Estudos Prospectivos , Brasil/epidemiologia , Filogenia , Estudos Soroepidemiológicos , Febre de Chikungunya/epidemiologia , Anticorpos Antivirais , Dengue/diagnóstico , Dengue/epidemiologia , Anticorpos Neutralizantes/genética , Imunoglobulina G , Imunoglobulina M
3.
Mem Inst Oswaldo Cruz ; 108(1): 119-22, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23440127

RESUMO

Human respiratory syncytial virus (HRSV) causes severe infections among children and immunocompromised patients. We compared HRSV infections among Haematopoietic Stem Cell Transplant program (HSCT) patients and children using direct immunofluorescence (DFA), point-of-care RSV Bio Easy® and a polymerase chain reaction (PCR) assay. Overall, 102 samples from HSCT patients and 128 from children obtained positivity rate of 18.6% and 14.1% respectively. PCR sensitivity was highest mainly on samples collected after five days of symptoms onset. A combination of both DFA and reverse transcriptase-PCR methods for HSCT high-risk patients is the best diagnostic flow for HRSV diagnosis among these patients.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Infecções por Vírus Respiratório Sincicial/diagnóstico , Vírus Sincicial Respiratório Humano/genética , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Criança , Pré-Escolar , Técnica Direta de Fluorescência para Anticorpo , Neoplasias Hematológicas/cirurgia , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Nasofaringe/virologia , RNA Viral/análise , Infecções por Vírus Respiratório Sincicial/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
4.
Int Immunopharmacol ; 106: 108573, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35183035

RESUMO

Human respiratory syncytial virus (hRSV) is an infectious agent in infants and young children which there are no vaccines or drugs for treatment. Neutrophils are recruited for airway, where they are stimulated by hRSV to release large amounts of neutrophil extracellular traps (NETs). NETs are compound by DNA and proteins, including microbicidal enzymes. They constitute a large part of the mucus accumulated in the lung of patients, compromising their breathing capacity. In contrast, NETs can capture/inactivate hRSV, but the molecules responsible for this effect are unknown. OBJECTIVES: We selected microbicidal NET enzymes (elastase, myeloperoxidase, cathepsin-G, and proteinase-3) to assess their anti-hRSV role. METHODS AND RESULTS: Through in vitro assays using HEp-2 cells, we observed that elastase, proteinase-3, and cathepsin-G, but not myeloperoxidase, showed virucidal effects even at non-cytotoxic concentrations. Elastase and proteinase-3, but not cathepsin-G, cleaved viral F-protein, which is responsible for viral adhesion and fusion with the target cells. Molecular docking analysis indicated the interaction of these macromolecules in the antigenic regions of F-protein through the active regions of the enzymes. CONCLUSIONS: Serine proteases from NETs interact and inactive hRSV. These results contribute to the understanding the role of NETs in hRSV infection and to designing treatment strategies for the inflammatory process during respiratory infections.


Assuntos
Armadilhas Extracelulares , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Serina Proteases , Armadilhas Extracelulares/enzimologia , Humanos , Simulação de Acoplamento Molecular , Infecções por Vírus Respiratório Sincicial/metabolismo , Serina Proteases/metabolismo
5.
Int J Infect Dis ; 102: 437-439, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33130201

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in December 2019 and quickly spread around the world, forcing global health authorities to develop protocols for its diagnosis. Here we report dimer formation in the N2 primers-probe set (CDC 2019-nCoV Real-Time RT-PCR) used in the diagnostic routine, and propose alternatives to reduce dimerization events. Late unspecific amplifications were visualized in 56.4% of negative samples and 57.1% of no-template control, but not in positive samples or positive control. In silico analysis and gel electrophoresis confirmed the dimer formation. The RT-qPCR parameters were optimized and the late unspecific amplifications decreased to 11.5% in negative samples and no-template control. The adjustment of PCR parameters was essential to reduce the risk of false-positives results and to avoid inclusive results requiring repeat testing, which increases the costs and generates delays in results or even unnecessary requests for new samples.


Assuntos
COVID-19/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , SARS-CoV-2 , Teste para COVID-19 , Primers do DNA , Humanos , RNA Viral/análise , Estudos Retrospectivos
6.
Viruses ; 12(5)2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32375411

RESUMO

Human Adenovirus species C (HAdV-C) is the most common etiologic agent of respiratory disease. In the present study, we characterized the nearly full-length genome of one potential new HAdV-C recombinant strain constituted by Penton and Fiber proteins belonging to type 89 and a chimeric Hexon protein of types 1 and 89. By using viral metagenomics techniques, we screened out, in the states of Tocantins and Pará, Northern and North regions of Brazil, from 2010 to 2016, 251 fecal samples of children between 0.5 to 2.5 years old. These children were presenting acute diarrhea not associated with common pathogens (i.e., rotavirus, norovirus). We identified two HAdV-C strains in two distinct patients. Phylogenetic analysis performed using all complete genomes available at GenBank database indicated that one strain (HAdV-C BR-245) belonged to type 1. The phylogenetic analysis also indicated that the second strain (HAdV-C BR-211) was located at the base of the clade formed by the newly HAdV-C strains type 89. Recombination analysis revealed that strain HAdV-C BR-211 is a chimera in which the variable regions of Hexon gene combined HAdV-C1 and HAdV-C89 sequences. Therefore, HAdV-C BR-211 strain possesses a genomic backbone of type HAdV-C89 and a unique insertion of HAdV-C1 in the Hexon sequence. Recombination may play an important driving force in HAdV-C diversity and evolution. Studies employing complete genomic sequencing on circulating HAdV-C strains in Brazil are needed to understand the clinical significance of the presented data.


Assuntos
Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , Genoma Viral , Adenovírus Humanos/classificação , Adenovírus Humanos/isolamento & purificação , Sequência de Aminoácidos , Brasil , Proteínas do Capsídeo/genética , Evolução Molecular , Genômica , Filogenia , Recombinação Genética
7.
Cad. Saúde Pública (Online) ; 40(3): e00076723, 2024. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1550195

RESUMO

Resumo A temperatura do ar é um fator climático que afeta a incidência da dengue, com efeitos variando conforme o tempo e o espaço. Investigamos a relação entre a temperatura mínima do ar e a incidência da doença em Minas Gerais, Brasil, e avaliamos a influência de variáveis socioeconômicas e geográficas nessa relação, calculando-se o risco relativo (RR). Este é um estudo de série temporal com análise conduzida em três etapas distintas: modelagem por uso de distributed lag non-linear model (modelos não-lineares distributivos com defasagem), metanálise dos modelos obtidos e metarregressão com dados geográficos e socioeconômicos. A temperatura mínima foi um fator de proteção quando em temperaturas frias extremas (RR = 0,65; IC95%: 0,56-0,76) e moderadas (RR = 0,71; IC95%: 0,64-0,79) e fator de risco em temperaturas de calor moderado (RR = 1,15; IC95%: 1,07-1,24), mas não em extremo (RR = 1,1; IC95%: 0,99-1,22). A heterogeneidade dos modelos foi elevada (I2 = 60%) e essa medida não foi alterada em metarregressão. Temperaturas frias moderadas e extremas causam efeito protetivo, enquanto moderadas quentes aumentam o risco. No entanto, a temperatura mínima do ar não explica nem a variabilidade da região, nem mesmo com as outras variáveis em metarregressão.


Abstract Air temperature is a climatic factor that affects the incidence of dengue, with effects varying according to time and space. We investigated the relationship between minimum air temperature and dengue incidence in Minas Gerais, Brazil, and evaluated the influence of socioeconomic and geographic variables on this relationship. This is a time series study with analysis conducted in three distinct stages: modeling using a distributed lag non-linear model, meta-analysis of models obtained, and meta-regression with geographic and socioeconomic data. Minimum temperature was a protective factor at extreme cold temperatures (RR = 0.65; 95%CI: 0.56-0.76) and moderate cold temperatures (RR = 0.71; 95%CI: 0.64-0.79), and a risk factor at moderate hot temperatures (RR = 1.15; 95%CI: 1.07-1.24), but not at extreme hot temperatures (RR = 1.1; 95%CI: 0.99-1.22). Heterogeneity of the models was high (I2 = 60%), which was also observed in meta-regression. Moderate and extreme cold temperatures have a protective effect, while moderate hot temperatures increase the risk. However, minimum air temperature does not explain the variability in the region, not even with the other variables in meta-regression.


Resumen La temperatura del aire es un factor climático que afecta la incidencia del dengue, con efectos que varían según el tiempo y el territorio. Investigamos la relación entre la temperatura mínima del aire y la incidencia de la enfermedad en Minas Gerais, Brasil, y evaluamos la influencia de variables socioeconómicas y geográficas en esta relación. Se trata de un estudio de serie temporal cuyo análisis se realiza en tres etapas distintas: modelación mediante el uso de distributed lag non-linear model (modelos distributivos no lineales con retraso), metaanálisis de los modelos obtenidos y metarregresión con datos geográficos y socioeconómicos. La temperatura mínima fue un factor de protección ante temperaturas extremadamente frías (RR = 0,65; IC95%: 0,56-0,76) y moderadas (RR = 0,71; IC95%: 0,64-0,79) y factor de riesgo en temperaturas de calor moderado (RR = 1,15; IC95%: 1,07-1,24), pero no en extremo (RR = 1,1; IC95%: 0,99-1,22). La heterogeneidad de los modelos fue alta (I2 = 60%), y esta medida no se modificó en la metarregresión. Las temperaturas frías moderadas y extremas tienen un efecto protector, mientras que las temperaturas moderadamente altas aumentan el riesgo. Sin embargo, la temperatura mínima del aire no explica la variabilidad de la región, ni siquiera con las demás variables en metarregresión.

8.
J Clin Virol ; 116: 62-68, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31103803

RESUMO

BACKGROUND: Acute respiratory infections caused by viruses are among the leading causes of morbidity and mortality. The inflammatory response that follows viral infection is important for the control of virus proliferation. However, if overwhelming, may be associated with complicated outcomes. OBJECTIVES: We assessed the clinical characteristics of patients with severe acute respiratory illness (SARI) evolving to acute respiratory distress syndrome (ARDS) and the factors related to death. STUDY DESIGN: Prospective study in 273 adult patients with SARI performed in a university-affiliated 800-bed hospital serving an area of epidemiologic vigilance of 102 municipalities and more than 2 million inhabitants. Influenza A (H1N1) 2009 (A/H1N1), influenza A H3N2, and influenza B were tested in all patients by RT-PCR. RESULTS: The overall hospital mortality rate was 17.6%. A total of 30.4% of patients tested positive for influenza A/H1N1. Patients with SARI that evolved to ARDS took significantly longer to take the first dose of oseltamivir (6.0 vs 1.0 days, p=0.002). Patients with H1N1 positive tests had almost 3 times higher probability of death, despite having significantly less comorbidities (p=0.027). The influenza A/H1N1 pdm09 vaccine reduced the odds of death by 78%. Nonsurvivors had a more intense inflammatory response than did survivors at 48 h (C-reactive protein: 31.0 ± 17.5 vs. 14.6 ± 8.9 mg/dl, p=0.001) as well as a more positive fluid balance. CONCLUSIONS: Hospital mortality associated with influenza H1N1-associated SARI and ARDS continued to be high years after the 2009 pandemic in a population with low vaccine coverage. Antiviral treatment started more than two days after onset of symptoms was more frequently associated with ARDS and death and, having had vaccine against influenza A (H1N1) was a factor independently related to survival.


Assuntos
Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/mortalidade , Influenza Humana/virologia , Infecções Respiratórias/mortalidade , Infecções Respiratórias/virologia , Adulto , Idoso , Antivirais/uso terapêutico , Feminino , Mortalidade Hospitalar , Humanos , Inflamação/mortalidade , Inflamação/virologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vacinas contra Influenza/administração & dosagem , Influenza Humana/tratamento farmacológico , Influenza Humana/patologia , Masculino , Pessoa de Meia-Idade , Oseltamivir/uso terapêutico , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/mortalidade , Síndrome do Desconforto Respiratório/prevenção & controle , Síndrome do Desconforto Respiratório/virologia , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/patologia , Fatores de Risco , Tempo para o Tratamento
9.
Diagn Microbiol Infect Dis ; 60(4): 445-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18234464

RESUMO

A duplex reverse transcriptase polymerase chain reaction-restriction fragment length polymorphism for influenza virus subtyping was applied to 412 patient samples. The assay was able to discriminate all 47 influenza A H1N1 and H3N2 viruses. This rapid technique assessed if positive samples were current circulating strains or an emergent one and could be used as the 1st test in prepandemic stages.


Assuntos
Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/virologia , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Brasil , Humanos
10.
Influenza Other Respir Viruses ; 12(3): 326-330, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29078028

RESUMO

BACKGROUND: The respiratory syncytial virus (RSV) is recognized as an important cause of respiratory tract infections. Immunocompromised patients, healthcare workers (HCWs) and children contacts are at increased risk of acquiring the infection. However, the impact of asymptomatic infection in transmission has not been well studied. OBJECTIVES: this study evaluated the frequency and viral load (VL) of RSV in nasal swab samples of individuals with different risk factors for acquiring infection in a university hospital in Sao Paulo, Brazil. METHODS: We included 196 symptomatic children and their 192 asymptomatic caregivers, 70 symptomatic and 95 asymptomatic HCWs, 43 samples from symptomatic HIV-positive outpatients, and 100 samples of asymptomatic HIV patients in the period of 2009-2013. RESULTS: RSV infection was detected in 10.1% (70/696) of samples, 4.4% (17/387) of asymptomatic patients, and 17.1% (53/309) from symptomatic patients. (P < .0001). The VL of symptomatic patients (4.7 log copies/mL) was significantly higher compared to asymptomatic patients (2.3 log copies/mL). RSV detection among asymptomatic caregivers (6.8%; 13/192) was significantly higher compared to other asymptomatic adults, HIV and HCWs (2.0%; 4/195; P = .0252). A close contact with an infected child at home was an important risk to RSV acquisition [OR 22.6 (95% CI 4.8-106.7)]. Children who possibly transmitted the virus to their asymptomatic contacts had significantly higher viral load than children who probably did not transmit (P < .0001). CONCLUSIONS: According to our results, it is important to know if people circulating inside the hospital have close contact with acute respiratory infected children.


Assuntos
Infecções Assintomáticas/epidemiologia , Hospitais Universitários , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/transmissão , Carga Viral , Adulto , Brasil/epidemiologia , Cuidadores/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Pessoal de Saúde/estatística & dados numéricos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Nariz/virologia , Reação em Cadeia da Polimerase em Tempo Real , Vírus Sinciciais Respiratórios/genética , Fatores de Risco
11.
Genome Announc ; 6(17)2018 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-29700140

RESUMO

Human bocavirus (HBoV) is commonly associated with acute respiratory tract illness and gastroenteritis. We report six complete genomic sequences of HBoV strains from patients with gastroenteritis in Belém do Pará and Tocantins in the North Region of Brazil. Phylogenetic analysis indicated that the six HBoV strains belong to genotypes 1, 2, and 3.

12.
PLoS Negl Trop Dis ; 12(5): e0006525, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29813061

RESUMO

The dynamics of dengue virus (DENV) circulation depends on serotype, genotype and lineage replacement and turnover. In São José do Rio Preto, Brazil, we observed that the L6 lineage of DENV-1 (genotype V) remained the dominant circulating lineage even after the introduction of the L1 lineage. We investigated viral fitness and immunogenicity of the L1 and L6 lineages and which factors interfered with the dynamics of DENV epidemics. The results showed a more efficient replicative fitness of L1 over L6 in mosquitoes and in human and non-human primate cell lines. Infections by the L6 lineage were associated with reduced antigenicity, weak B and T cell stimulation and weak host immune system interactions, which were associated with higher viremia. Our data, therefore, demonstrate that reduced viral immunogenicity and consequent greater viremia determined the increased epidemiological fitness of DENV-1 L6 lineage in São José do Rio Preto.


Assuntos
Vírus da Dengue/imunologia , Dengue/imunologia , Aedes/fisiologia , Aedes/virologia , Animais , Linfócitos B/imunologia , Brasil , Estudos de Coortes , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/classificação , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Genótipo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Filogenia , Linfócitos T/imunologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-28793016

RESUMO

Rotavirus is the main global cause of severe childhood diarrhoea among children. In 2006, Rotarix® (G1P[8]) was introduced into Brazil's National Immunization Program. The vaccine coverage rate was 84.4% in 2009. Evidences of increasing G2P[4] after 2006 opened up the discussion about the vaccine effectiveness to non-G1 strains. The aim of this study was to identify the circulating rotavirus genotypes in two Brazilian regions during 2009. A total of 223 positive samples by immunochromatography and latex agglutination assay from the Northeast (Bahia/Pernambuco States) and Southeast (São Paulo/Rio de Janeiro States) regions were included in the study. The samples were submitted to genotyping by nested-PCR according to VP7(G) and VP4(P) and 175 samples (78.5%) were able to be characterized. Considering the characterization of VP7, the G-types detected were G1, G2, and G4 in the Northeast, and G2, G3, G5, and G9 in the Southeast. Considering the characterization of VP4, the P-types detected were P[4], P[8], and P[6]/P[9] in the Northeast and the Southeast. The most frequent mixed types found were G2P[4]/G2P[NT](81.4%), G2P[6](5.2%), G1P[6](5.2%) in the Northeast, and G2P[4]/G2P[NT](78.8%), G2P[6](8.2%), G9P[8](4.7%) in the Southeast. Among immunized individuals whose age ranged from 0-4 years, the G2P[4]/G2P[NT] genotype was identified in 91,0% of cases, and among non-immunized individuals of the same age, the G2P[4]/G2P[NT] genotype was identified in 85.7% of the cases. In accordance with the high level of vaccine coverage, the data suggest that the circulation of G2P[4] in these regions had a considerable increase after the introduction of Rotarix®.


Assuntos
Diarreia/virologia , Infecções por Rotavirus/virologia , Rotavirus/genética , Adolescente , Adulto , Brasil , Criança , Pré-Escolar , Cromatografia de Afinidade , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Filogenia , RNA Viral/genética , Rotavirus/isolamento & purificação , Estações do Ano , Adulto Jovem
15.
Rev Paul Pediatr ; 33(2): 136-41, 2015.
Artigo em Português | MEDLINE | ID: mdl-25890444

RESUMO

OBJECTIVE: Adenoviruses play an important role in the etiology of severe acute lower respiratory infection, especially in young children. The aim of the present study was to evaluate the Human Adenovirus (HAdV) detection by different methods (Direct Fluorescence Assay - DFA and Nested Polymerase Chain Reaction - nested PCR), among samples collected from different groups of pediatric patients. METHODS: Collection of samples was made in children with congenital heart disease (CHD - 123 nasal aspirates collected in the years of 2005, 2007 and 2008) and in community children (CC - 165 nasal aspirates collected in 2008). Children were eligible if they presented acute respiratory infection (ARI) of probable viral etiology, within up to 7 days of symptoms' onset. All studied samples were evaluated by DFA and nested PCR assay. RESULTS: Of the 290 samples included during the study period, 43 (14.8%) were positive on at least one test: 17/165 (10.3%) of the CC and 26/125 (20.8%) of the CHD children. The nested PCR detection rates in the community children were 15/165 (9.1%), and for children with CHD, 24/125 (19.2%). Molecular method showed higher detection rates when compared to the DFA test (p<0.001). Univariate analysis showed that children with congenital heart disease presented a significantly higher chance for acquiring the HAdV (Odds Ratio 2.3; 95% CI: 1.18-4.43). CONCLUSIONS: Based on data obtained in the present evaluation, we suggest that a routine surveillance should be performed in high risk patients by molecular methods, thus improving diagnostic flow and efficiency.


Assuntos
Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/isolamento & purificação , Infecções Respiratórias/virologia , Criança , Estudos Transversais , Feminino , Técnica Direta de Fluorescência para Anticorpo , Humanos , Lactente , Recém-Nascido , Masculino , Técnicas de Diagnóstico Molecular , Reação em Cadeia da Polimerase
16.
Rev Inst Med Trop Sao Paulo ; 54(6): 307-10, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23152312

RESUMO

BACKGROUND AND OBJECTIVES: Human Bocavirus (HBoV) has been described since 2005 as an etiological agent of respiratory virus infections. From 2001 to 2008 we investigated the etiology of HBoV among adults and children in different groups at risk of presenting complications arising from acute respiratory infection, the investigation was carried out in a tertiary hospital health care system in Brazil. METHODS: HBoV DNA was assayed in 598 respiratory samples from community and hospitalized patients by PCR. RESULTS: Of the 598 tested samples, 2.44% (8/328) of children, including five children with heart disease, and 0.4% (1/270) of adult bone-marrow-transplant were HBoV positive. CONCLUSIONS: These data suggested lower HBoV frequency among different at-risk patients and highlights the need to better understand the real role of HBoV among acute respiratory symptomatic patients.


Assuntos
DNA Viral/análise , Bocavirus Humano/genética , Infecções por Parvoviridae/epidemiologia , Infecções Respiratórias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Criança , Pré-Escolar , DNA Viral/genética , Bocavirus Humano/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Infecções por Parvoviridae/diagnóstico , Reação em Cadeia da Polimerase , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/virologia , Fatores de Risco , Estações do Ano , Adulto Jovem
17.
Rev Soc Bras Med Trop ; 45(5): 563-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23152337

RESUMO

INTRODUCTION: Influenza A H1N1 2009 is associated with a high morbidity rate among children around the world, including Brazil. This survey was conducted on samples of symptomatic children (< 12 years) to investigate the influenza virus as the etiological agent of respiratory infections in a day care school in a health facility during the first and second pandemic wave of H1N1 (2009-2010) in São Paulo, Brazil. METHODS: Influenza infections were determined by real-time PCR in 34% (47/137) of children with a median age of 5 years (8 months - 12 years), from June to October 2009 and in 16% (14/85) of those with median age of 6 years (1-12 years), from March to November 2010. RESULTS: In general, most positive cases (64%) occurred in children aged 5-12 years, this age group was significantly the most affected (39.8%, p = 0.001, OR = 8.3, CI 95% 1.9-36.9). Wheezing was reported by 31% (19/61) and dyspnea by 23% (14/61) of the studied patients. An outbreak of influenza H1N1 with an attack rate of 35.7% among children (median age 6 years) was documented in April 2010, before the vaccination campaign against the pandemic virus was extended for children up to 5 years in Brazil. CONCLUSIONS: Therefore, the study reinforces the recommendation to immunize school children to reduce the incidence of the disease.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana/epidemiologia , Pandemias , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Modelos Logísticos , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/etiologia , Instituições Acadêmicas , Vigilância de Evento Sentinela
18.
Braz J Infect Dis ; 15(3): 220-4, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21670921

RESUMO

INTRODUCTION: During the first pandemic wave of the influenza A H1N1 2009 virus, morbidity was particularly high in Brazil. Hospitalizations resulting from severe respiratory disease due to suspected influenza-like illness created an opportunity to identify other respiratory viruses causing lower respiratory infections. OBJECTIVE: The purpose of this study was to assess viral etiologies among samples collected during the first pandemic wave of H1N1 2009 from hospitalized patients with suspected cases in a Brazilian Sentinel Hospital. PATIENTS AND METHODS: Viral etiologies were investigated in samples from 98 children and 61 adults with fever, cough and dyspnea who were admitted to São Paulo Sentinel Hospital with suspected H1N1 infection. RESULTS: From August to November 2009, in 19.5% (31/159) of the samples 2009 H1N1 virus was detected with 23% (14/61) in adults (median age 25 years, range: 14-55 years) and 18.4% (17/92) in children (median age 5 years, range: 4 months - 11 years). Among the negative samples, a wide range of causative etiologic agents was identified. Human rhinovirus was the most frequent virus (23.91%) in children and human metapneumovirus (11.48%) was the second most frequent in adults, following 2009 H1N1 virus (22.95%). CONCLUSION: These data highlight the need to diagnose other viral infections that can co-circulate with influenza and may have been neglected by physicians as causes of severe respiratory diseases.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/virologia , Pandemias/estatística & dados numéricos , Infecções Respiratórias/virologia , Vigilância de Evento Sentinela , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Criança , Pré-Escolar , Hospitalização , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/epidemiologia , Pessoa de Meia-Idade , Infecções Respiratórias/epidemiologia , Adulto Jovem
19.
Rev Soc Bras Med Trop ; 44(1): 18-21, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21340401

RESUMO

INTRODUCTION: Acute respiratory tract infections are the most common illness in all individuals. Rhinoviruses have been reported as the etiology of more than 50% of respiratory tract infections worldwide. The study prospectively evaluated 47 elderly individuals from a group of 384 randomly assigned for acute respiratory viral infections (cold or flu) and assessed the occurrence of human rhinovirus (HRV), influenza A and B, respiratory syncytial virus and metapneumovirus (hMPV) in Botucatu, State of São Paulo, Brazil. METHODS: Forty-nine nasal swabs collected from 47 elderly individuals following inclusion visits from 2002 to 2003 were tested by GenScan RT-PCR. HRV-positive samples were sequenced for phylogenetic analysis. RESULTS: No sample was positive for influenza A/B or RSV. HRV was detected in 28.6% (14/47) and hMPV in 2% (1/47). Of 14 positive samples, 9 isolates were successfully sequenced, showing the follow group distribution: 6 group A, 1 group B and 2 group C HRVs. CONCLUSIONS: The high incidence of HRV during the months of the influenza season requires further study regarding HRV infection impact on respiratory complications among this population. Infection caused by HRV is very frequent and may contribute to increasing the already high demand for healthcare during the influenza season.


Assuntos
Metapneumovirus/genética , Orthomyxoviridae/genética , Vírus Sinciciais Respiratórios/genética , Infecções Respiratórias/virologia , Rhinovirus/genética , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Filogenia , Estudos Prospectivos , Infecções Respiratórias/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano
20.
J Bras Pneumol ; 37(5): 655-8, 2011.
Artigo em Inglês, Português | MEDLINE | ID: mdl-22042398

RESUMO

In 2010, 96 patients suspected of being infected with the influenza A (H1N1) virus were hospitalized at the Hospital São Paulo, located in the city of São Paulo, Brazil. Of those 96 patients, 4 (4.2%) were found to be infected with influenza A virus-3 with influenza A (H1N1) and 1 with seasonal influenza A-and 2 patients (2.1%) were found to be infected with influenza B virus. Most (63.5%) of the suspected cases occurred in children, as did half of the positive cases. The second wave of influenza A (H1N1) infection was weaker in São Paulo. The decrease in the number of hospitalizations for H1N1 infection in 2010 might be attributable to vaccination.


Assuntos
Hospitalização/estatística & dados numéricos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Influenza Humana/classificação , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade , Vigilância de Evento Sentinela , Fatores de Tempo , Vacinação/normas , Adulto Jovem
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