RESUMO
Since the first evidence of human parvovirus B19 (B19V) infection in late 80s, several studies have been conducted to clarify the spectrum of clinical diseases in Brazil. B19V infection is prevalent in the general population and has exhibited a cyclical pattern of occurrence every 4-5 years, with the predominance of genotype 1 over 3b. During epidemic periods the wide range of clinical conditions, such as ertythema infectiosum, arthropathy, transient aplastic crisis, nonimmune hydrops fetalis and B19V-hepatitis were diagnosed. However, many infections are likely asymptomatic or have a self-limiting clinical course and are not readly diagnosed. Besides, the similarity of the symptoms of ertythema infectiosum to other rash diseases and the broadly circulation of arboviruses makes differential diagnosis more difficult. In this article, we provide a historical comprehensive overview of the research on parvovirus B19 conducted in Brazil, with a focus on the clinical and epidemiological aspects of the infection.
Assuntos
Infecções por Parvoviridae/virologia , Parvovirus B19 Humano/fisiologia , Brasil/epidemiologia , Doenças Hematológicas/diagnóstico , Doenças Hematológicas/epidemiologia , Doenças Hematológicas/virologia , Humanos , Artropatias/diagnóstico , Artropatias/epidemiologia , Artropatias/virologia , Infecções por Parvoviridae/diagnóstico , Infecções por Parvoviridae/epidemiologia , Parvovirus B19 Humano/classificação , Parvovirus B19 Humano/genética , Parvovirus B19 Humano/isolamento & purificaçãoRESUMO
Aim: In this study, we investigated the presence of B19V in liver tissues from patients with acute liver failure (ALF) and evaluated the viral activity in infected liver. Methods: Serum and liver samples from 30 patients who underwent liver transplantation for ALF were investigated for B19V infection by real-time PCR, serological tests and examination of B19V mRNA (transcript) expression in the liver. Results: The serum and liver samples from seven patients were B19V DNA positive (103-105 copies/ml). Most of them presented detectable anti-B19V IgG, indicating persistent infection. B19V mRNA was detected in all patients, demonstrating intra-hepatic replication. Conclusion: B19V infection of the liver during the course of non-A-E ALF suggested a role of B19V, which produced the worst outcome in co-infected patients and in patients with cryptogenic ALF, in liver damage.
Assuntos
Falência Hepática Aguda/virologia , Parvovirus B19 Humano/genética , Adolescente , Adulto , Anticorpos Antivirais/sangue , Criança , DNA Viral/genética , Feminino , Humanos , Fígado/patologia , Fígado/cirurgia , Fígado/virologia , Falência Hepática Aguda/sangue , Falência Hepática Aguda/patologia , Falência Hepática Aguda/terapia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Parvovirus B19 Humano/classificação , Parvovirus B19 Humano/isolamento & purificação , Filogenia , Adulto JovemRESUMO
Parvovirus B19 (B19V) infects individuals worldwide and is associated with an ample range of pathologies and clinical manifestations. B19V is classified into three distinct genotypes, all identified in Brazil. Here, we report a complete sequence of a B19V genotype 1A that was obtained by high-throughput metagenomic sequencing. This genome provides information that will contribute to the studies on B19V epidemiology and evolution.
Assuntos
Genoma Viral/genética , Parvovirus B19 Humano/genética , Brasil , Criança , Evolução Fatal , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Parvovirus B19 Humano/classificação , Análise de Sequência de DNARESUMO
Human Parvovirus B19 (B19V) is a recognized cause of life-threatening conditions among patients with hemoglobinopathies. This study investigates B19V infection in patients with sickle cell disease and ß-thalassemia using different experimental approaches. A total of 183 individuals (144 with sickle cell disease and 39 with ß-thalassemia major) and 100 healthy blood donors were examined for B19V using anti-B19V IgG enzyme immunoassay, quantitative PCR, DNA sequencing, and phylogenetic analysis. Viremia was documented in 18.6% of patients and 1% of donors, and was generally characterized by low viral load (VL); however, acute infections were also observed. Anti-B19V IgG was detected in 65.9% of patients with sickle cell disease and in 60% of donors, whereas the patients with thalassemia exhibited relatively low seroreactivity. The seroprevalence varied among the different age groups. In patients, it progressively increased with age, whereas in donors it reached a plateau. Based on partial NS1 fragments, all isolates detected were classified as subgenotype 1A with a tendency to elicit genetically complex infections. Interestingly, quasispecies occurred in the plasma of not only patients but also donors with even higher heterogeneity. The partial NS1 sequence examined did not exhibit positive selection. Quantitation of B19V with a conservative probe is a technically and practically useful approach. The extensive spread of B19V subgenotype 1A in patients and donors and its recent introduction into the countryside of the São Paulo State, Brazil were demonstrated; however, it is difficult to establish a relationship between viral sequences and the clinical outcomes of the infection.
Assuntos
Anemia Falciforme/complicações , Doadores de Sangue , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Parvovirus B19 Humano/classificação , Parvovirus B19 Humano/genética , Talassemia beta/complicações , Adolescente , Adulto , Fatores Etários , Idoso , Anticorpos Antivirais/sangue , Brasil/epidemiologia , Criança , Pré-Escolar , Análise por Conglomerados , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Humanos , Imunoglobulina G/sangue , Lactente , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Parvovirus B19 Humano/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Estudos Soroepidemiológicos , Proteínas não Estruturais Virais/genética , Adulto JovemRESUMO
Human parvovirus B19 (B19V) infection can be a life-threatening condition among patients with hereditary (chronic) hemolytic anemias. Our objective was to characterize the infection molecularly among patients with sickle cell disease and thalassemia. Forty-seven patients (37 with sickle cell disease, and 10 with ß-thalassemia major) as well as 47 healthy blood donors were examined for B19V infection by anti-B19V IgG enzyme immunoassay, quantitative PCR, which detects all B19V genotypes, and DNA sequencing. B19V viremia was documented in nine patients (19.1%) as two displayed acute infection and the rest had a low titre viremia (mean 3.4 × 10(4) copies/mL). All donors were negative for B19V DNA. Anti-B19V IgG was detected in 55.3% of the patients and 57.4% among the donors. Based on partial NS1 fragments, all patient isolates were classified as genotype 1 and subgenotype 1A. The evolutionary events of the examined partial NS1 gene sequence were associated with a lack of positive selection. The quantification of all B19V genotypes by a single hydrolytic probe is a technically useful method, but it is difficult to establish relationships between B19V sequence characteristics and infection outcome.
Assuntos
Anemia Falciforme/virologia , Parvovirus B19 Humano/genética , Talassemia beta/virologia , Adolescente , Adulto , Idoso , Anemia Falciforme/epidemiologia , Anemia Falciforme/genética , Doadores de Sangue , Brasil , Criança , Pré-Escolar , DNA/genética , DNA Viral/sangue , DNA Viral/genética , Genótipo , Humanos , Pessoa de Meia-Idade , Infecções por Parvoviridae/diagnóstico , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/genética , Infecções por Parvoviridae/virologia , Parvovirus B19 Humano/classificação , Parvovirus B19 Humano/isolamento & purificação , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Talassemia/genética , Viremia/diagnóstico , Viremia/genética , Adulto Jovem , Talassemia beta/epidemiologia , Talassemia beta/genéticaRESUMO
To understand the evolutionary dynamics of human parvovirus B19, we analyzed VP1 and VP2 gene sequences of B19 sampled from Belém (Amazon), the city of São Paulo, Brazil and globally. Our analysis revealed a strikingly different pattern of evolutionary change for those viral lineages introduced into Belém, which exhibited a higher rate of nonsynonymous substitutions compared to those viruses sampled from other locations. We propose that difference this is due to the high prevalence of B19 in Belém (up to 85%) compared to other locations (prevalences of approximately 50%), which imposes a more intense selection pressure. Hence, those B19 lineages introduced into Belém experienced an elevated rate of amino acid change, driven by positive selection, in order to generate serial re-infections in a small web of transmission, which can be thought of as an evolutionary "pressure pan".
Assuntos
Evolução Molecular , Parvovirus B19 Humano/genética , Teorema de Bayes , Brasil , Proteínas do Capsídeo/genética , DNA Viral/genética , Eritema Infeccioso/virologia , Genes Virais , Humanos , Modelos Genéticos , Dados de Sequência Molecular , Infecções por Parvoviridae/virologia , Parvovirus B19 Humano/classificação , Parvovirus B19 Humano/isolamento & purificação , Filogenia , Seleção GenéticaRESUMO
Three genotypes (1-3) of human parvovirus B19 have been identified. Analysis of 13 nearly full-length genotype 3 sequences from Ghana, Europe and Brazil identified two genetically distinct clusters. The classification of genotype 3 strains into two subtypes (B19/3a and B19/3b) is proposed. The rate of evolutionary change of B19 genotype 3 strains (2 x 10(-4) nucleotide substitutions per site per year) was similar to those of B19 genotype 1 and carnivore parvoviruses, supporting the hypothesis that high mutation rates are characteristic of members of the family Parvoviridae. The estimated divergence time between B19/3a and B19/3b is 525 years. In Ghana, subtype B19/3a is predominant.