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1.
PLoS One ; 15(3): e0227962, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32155152

RESUMO

OBJECTIVE: Since the 2009 influenza pandemic, Latin American (LA) countries have strengthened their influenza surveillance systems. We analyzed influenza genetic sequence data from the 2017 through 2018 Southern Hemisphere (SH) influenza season from selected LA countries, to map the availability of influenza genetic sequence data from, and to describe, the 2017 through 2018 SH influenza seasons in LA. METHODS: We analyzed influenza A/H1pdm09, A/H3, B/Victoria and B/Yamagata hemagglutinin sequences from clinical samples from 12 National Influenza Centers (NICs) in ten countries (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Mexico, Paraguay, Peru and Uruguay) with a collection date from epidemiologic week (EW) 18, 2017 through EW 43, 2018. These sequences were generated by the NIC or the WHO Collaborating Center (CC) at the U.S Centers for Disease Control and Prevention, uploaded to the Global Initiative on Sharing All Influenza Data (GISAID) platform, and used for phylogenetic reconstruction. FINDINGS: Influenza hemagglutinin sequences from the participating countries (A/H1pdm09 n = 326, A/H3 n = 636, B n = 433) were highly concordant with the genetic groups of the influenza vaccine-recommended viruses for influenza A/H1pdm09 and influenza B. For influenza A/H3, the concordance was variable. CONCLUSIONS: Considering the constant evolution of influenza viruses, high-quality surveillance data-specifically genetic sequence data, are important to allow public health decision makers to make informed decisions about prevention and control strategies, such as influenza vaccine composition. Countries that conduct influenza genetic sequencing for surveillance in LA should continue to work with the WHO CCs to produce high-quality genetic sequence data and upload those sequences to open-access databases.


Assuntos
Evolução Molecular , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Orthomyxoviridae/genética , Pandemias/prevenção & controle , Conjuntos de Dados como Assunto , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Vacinas contra Influenza/imunologia , Influenza Humana/epidemiologia , Influenza Humana/microbiologia , América Latina/epidemiologia , Orthomyxoviridae/imunologia , Orthomyxoviridae/isolamento & purificação , Filogenia
3.
BMC Res Notes ; 9: 296, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27267995

RESUMO

BACKGROUND: The virulence and pathogenicity of different influenza strains are responsible for a more or less severe disease. Recent studies have attempted to understand how host genetic factors may influence the clinical presentation of the disease. In the present study, the His131Arg (rs1801274) polymorphism was investigated in individuals from a Brazilian admixed population with a diagnosis of influenza A(H1N1)pdm09 infection. METHODS: In the present study, the influence of the His131Arg (rs1801274) polymorphism, a variant of the FCGR2A gene, was investigated in 436 patients with a diagnosis of influenza A(H1N1)pdm09, evaluated at health services in the northern and northeastern regions of Brazil between June 2009 and August 2010. Patients were divided into a group of non-hospitalized patients (n = 192) and a group of hospitalized patients (n = 244; 100 of them died). RESULTS: No significant difference in the allele or genotype frequencies of the rs1801274 polymorphism was observed between groups (p = 0.952 and p = 0.388). Multinomial logistic regression showed no effect of the rs1801274 polymorphism on severity or death of patients from the Brazilian admixed population (p = 0.368 and p = 0.469). CONCLUSIONS: The rs1801274 polymorphism is not associated with severe disease in patients infected with influenza A(H1N1)pdm09.


Assuntos
Substituição de Aminoácidos , Predisposição Genética para Doença/genética , Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento , Influenza Humana/genética , Polimorfismo de Nucleotídeo Único , Receptores de IgG/genética , Adolescente , Adulto , Alelos , Arginina/genética , Criança , Feminino , Frequência do Gene , Genótipo , Histidina/genética , Interações Hospedeiro-Patógeno , Humanos , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/patologia , Influenza Humana/virologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Adulto Jovem
4.
BMC Res Notes ; 8: 326, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26223981

RESUMO

BACKGROUND: Recent studies have tried to identify host genetic variants that could explain severe cases and deaths in infection with Influenza A(H1N1)pdm09, especially among children and young adults. CCR5 is a chemokine receptor expressed on T cells, macrophages and dendritic cells, which is an important mediator of leukocyte chemotaxis during the immune response. A deletion mutation (Δ32) in this gene interferes with the response of immune cells, impairing viral clearance. We evaluated the CCR5Δ32 polymorphism (rs333) in individuals of the Brazilian admixed population with a diagnosis of Influenza A(H1N1)pdm09 infection. METHODS: A total of 330 subjects with a diagnosis of Influenza A(H1N1)pdm09, evaluated at health services in the northern and northeastern regions of Brazil between June 2009 and August 2010, were genotyped for the Δ32 deletion (rs333). The cases were classified according to the progression of infection into a group of hospitalized patients (n = 156) and a group of non-hospitalized patients (n = 174). RESULTS: No significant differences in the allele or genotype frequencies of the CCR5Δ32 polymorphism were observed between non-hospitalized and hospitalized patients (p = 0.289 and p = 0.431, respectively). CONCLUSION: The Δ32 deletion in the CCR5 gene is not associated with an unfavorable outcome in patients infected with Influenza A(H1N1)pdm09 in the Brazilian admixed population.


Assuntos
Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/genética , Leucócitos Mononucleares/metabolismo , Receptores CCR5/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Brasil , Criança , Pré-Escolar , Feminino , Expressão Gênica , Hospitalização , Humanos , Lactente , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/patologia , Influenza Humana/virologia , Leucócitos Mononucleares/virologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Polimorfismo Genético , Cultura Primária de Células , Deleção de Sequência , Índice de Gravidade de Doença
5.
Infect Agent Cancer ; 9: 25, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25143783

RESUMO

BACKGROUND: The main cause of cervical cancer in the world is high risks human papillomavirus infection (mainly represented by HPV-16 and HPV-18), that are associated to the development of malign transformation of the epithelium. HPV prevalence exhibits a wide geographical variability and HPV-16 variants have been related to an increased risk of developing cervical intraepithelial lesion. The aim of this study was to describe DNA-HPV prevalence and HPV-16 variants among a women population from Northern Brazil. METHODS: One hundred and forty three women, during routine cervical cancer screening, at Juruti Project, fulfilled an epidemiological inquiry and were screened through a molecular HPV test. HPV-16 variants were determined by sequencing the HPV-16 E6 open reading frame. RESULTS: Forty two samples were considered HPV positive (29.4%). None of those had abnormal cytology results. HPV prevalence varied between different age groups (Z(U) = 14.62; p = <0.0001) and high-risk HPVs were more frequent among younger ages. The most prevalent type was HPV-16 (14%) and it variants were classified, predominantly, as European (87.5%). CONCLUSIONS: HPV prevalence in our population was higher than described by others and the most prevalent HPV types were high-risk HPVs. The European HPV-16 variant was the most prevalent among HPV-16 positive samples. Our study reinforces the fact that women with normal cytology and a positive molecular test for high-risk HPVs should be submitted to continuous follow up, in order to verify persistence of infection, promoting an early diagnosis of cervical cancer and/or its precursors.

6.
PLoS One ; 4(4): e5095, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19352506

RESUMO

Since 1999 the World Health Organization issues annually an additional influenza vaccine composition recommendation. This initiative aimed to extend to the Southern Hemisphere (SH) the benefits-previously enjoyed only by the Northern Hemisphere (NH)--of a vaccine recommendation issued as close as possible to the moment just before the onset of the influenza epidemic season. A short time between the issue of the recommendation and vaccine delivery is needed to maximize the chances of correct matching between putative circulating strains and one of the three strains present in the vaccine composition. Here we compare the effectiveness of the SH influenza vaccination adopted in Brazil with hypothetical alternative scenarios defined by different timings of vaccine delivery and/or composition. Scores were based on the temporal overlap between vaccine-induced protection and circulating strains. Viral data were obtained between 1999 and 2007 from constant surveillance and strain characterization in two Brazilian cities: Belém, located at the Equatorial region, and São Paulo, at the limit between the tropical and subtropical regions. Our results show that, among currently feasible options, the best strategy for Brazil would be to adopt the NH composition and timing, as in such case protection would increase from 30% to 65% (p<.01) if past data can be used as a prediction of the future. The influenza season starts in Brazil (and in the equator virtually ends) well before the SH winter, making the current delivery of the SH vaccination in April too late to be effective. Since Brazil encompasses a large area of the Southern Hemisphere, our results point to the possibility of these conclusions being similarly valid for other tropical regions.


Assuntos
Vacinas contra Influenza/administração & dosagem , Medicina Tropical , Brasil , Humanos , Guias de Prática Clínica como Assunto , Estações do Ano
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