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1.
J Med Virol ; 91(3): 378-384, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30231194

RESUMO

Enteric adenovirus (AdV), sapovirus (SaV), and human astrovirus (HAstV) are important pathogens involved in the gastroenteritis etiology. In this study, a total of 219 fecal samples and sera were collected from children hospitalized for acute gastroenteritis (AGE) in two large pediatric hospitals in Belém, from March 2012 to April 2015. The samples were analyzed by polymerase chain reaction (PCR) for AdV and HAstV (astrovirus) detection, and Nested-PCR and qPCR for SaV detection. AdV was detected in 50.2% (110/219) of the cases, with 42.7% (47/110) being sequenced and classified as: species F (63.9% - 30/47), A (4.2% - 2/47), B (6.4% - 3/47), C (17.1% - 8/47), D (4.2% - 2/47), and E (4.2% - 2/47). Of the 110 AdV-positive feces samples, 80 paired sera presented sufficient amounts and were also tested for this virus, of which 51 (63.7%) showed positive results and 26 (70.3%) pairs (feces plus sera) presented concordant results after sequencing being classified as: species F (21/26; 80.8%), A (1/26; 3.8%), B (1/26; 3.8%), and C (3/26; 11.5%). Overall, HAstV rate in the feces samples was 1.8% (4/219), including both HAstV-1a (2/4; 50%) and HAstV-2c (2/4; 50%). SaV was detected in 4.6% (10/219) of the fecal samples, out of which 50% (5/10) of the positive samples were characterized into the genogroups GI.1 (1), GI.2 (2), and GII.4 (2). These findings highlighted the important contributions of AdV, HAstV, and SaV in the enteric virus spectrum in our region and showed the high genetic diversity of AdV. In addition, it demonstrated for the first time in Brazil, the circulation of AdV in the serum of hospitalized children with AGE.


Assuntos
Infecções por Adenoviridae/epidemiologia , Gastroenterite/virologia , Variação Genética , Viremia/epidemiologia , Doença Aguda/epidemiologia , Adenoviridae/genética , Infecções por Adenoviridae/virologia , Infecções por Astroviridae/epidemiologia , Infecções por Astroviridae/virologia , Brasil/epidemiologia , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Criança , Pré-Escolar , Diarreia/epidemiologia , Diarreia/virologia , Feminino , Gastroenterite/epidemiologia , Genótipo , Hospitalização , Humanos , Lactente , Recém-Nascido , Masculino , Mamastrovirus/genética , Filogenia , Sapovirus/genética
2.
Mem Inst Oswaldo Cruz ; 113(11): e170538, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30379197

RESUMO

This study showed that laboratory markers of recent infection by dengue, Zika or chikungunya arboviruses were detected in the biological samples of approximately one-third of patients with encephalitis, myelitis, encephalomyelitis or Guillain-Barré syndrome, in a surveillance programme in Piauí state, Brazil, between 2015-2016. Fever and myalgia had been associated with these cases. Since in non-tropical countries most infections or parainfectious diseases associated with the nervous system are attributed to herpesviruses, enteroviruses, and Campylobacter jejuni, the present findings indicate that in tropical countries, arboviruses may now play a more important role and reinforce the need for their surveillance and systematic investigation in the tropics.


Assuntos
Vírus Chikungunya , Vírus da Dengue , Doenças do Sistema Nervoso/virologia , Zika virus , Doença Aguda , Vírus Chikungunya/genética , Vírus Chikungunya/imunologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Encefalite/diagnóstico , Encefalite/virologia , Encefalomielite Aguda Disseminada/diagnóstico , Encefalomielite Aguda Disseminada/virologia , ELISPOT , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/virologia , Humanos , Mielite Transversa/diagnóstico , Mielite Transversa/virologia , Doenças do Sistema Nervoso/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Zika virus/genética , Zika virus/imunologia
3.
PLoS One ; 13(3): e0194184, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29558516

RESUMO

The Human T-cell Lymphotropic Virus (HTLV-1) is a Deltaretrovírus that was first isolated in the 1970s, and associated with Adult T-cell Leucemia-Lymphoma (ATLL), and subsequently to Tropical Spastic Paraparesis-Myelopathy (TSP/HAM). The genetic diversity of the virus varies among geographic regions, although its mutation rate is very low (approximately 1% per thousand years) in comparison with other viruses. The present study determined the genetic diversity of HTLV-1 in the metropolitan region of Belém, in northern Brazil. Blood samples were obtained from patients at the UFPA Tropical Medicine Nucleus between January 2010 and December 2013. The DNA was extracted and the PX region of the HTLV was amplified using nested PCR. The positive samples were then digested using the Taq1 enzyme for the identification and differentiation of the HTLV-1 and HTLV-2. The 5'LTR region of the positive HTLV-1 samples were amplified by nested PCR, and then sequenced genetically. The phylogenetic analysis of the samples was based on the maximum likelihood method and the evolutionary profile was analyzed by the Bayesian approach. Overall, 78 samples tested positive for HTLV-1, and 44 were analyzed here. The aA (cosmopolitan-transcontinental) subtype was recorded in all the samples. The following evolutionary rates were recorded for the different subtypes-a: 2.10-3, b: 2.69. 10-2, c: 6.23. 10-2, d: 3.08. 10-2, e: 6. 10-2, f: 1.78. 10-3, g: 2.2. 10-2 mutations per site per year. The positive HTLV-1 samples tested in the present study were characterized by their low genetic diversity and high degree of stability.


Assuntos
Variação Genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Leucemia-Linfoma de Células T do Adulto/genética , Sequências Repetidas Terminais , Adulto , Brasil/epidemiologia , Feminino , Humanos , Leucemia-Linfoma de Células T do Adulto/enzimologia , Masculino
4.
Mem. Inst. Oswaldo Cruz ; 113(11): e170538, 2018. tab
Artigo em Inglês | LILACS | ID: biblio-1040584

RESUMO

This study showed that laboratory markers of recent infection by dengue, Zika or chikungunya arboviruses were detected in the biological samples of approximately one-third of patients with encephalitis, myelitis, encephalomyelitis or Guillain-Barré syndrome, in a surveillance programme in Piauí state, Brazil, between 2015-2016. Fever and myalgia had been associated with these cases. Since in non-tropical countries most infections or parainfectious diseases associated with the nervous system are attributed to herpesviruses, enteroviruses, and Campylobacter jejuni, the present findings indicate that in tropical countries, arboviruses may now play a more important role and reinforce the need for their surveillance and systematic investigation in the tropics.


Assuntos
Humanos , Vírus Chikungunya/genética , Vírus Chikungunya/imunologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Zika virus/genética , Zika virus/imunologia , Doença Aguda , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/virologia , Encefalite/diagnóstico , Encefalite/virologia , Encefalomielite Aguda Disseminada/diagnóstico , Encefalomielite Aguda Disseminada/virologia , ELISPOT , Mielite Transversa/diagnóstico , Mielite Transversa/virologia , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/virologia
5.
Rev Soc Bras Med Trop ; 50(5): 621-628, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29160508

RESUMO

INTRODUCTION: Acute gastroenteritis (AGE) is one of the most common causes of morbidity and mortality, especially among children from developing countries. Human adenovirus (HAdV) and sapovirus (SaV) are among the agents that cause AGE. The present study aimed to detect and genotype HAdV and SaV in 172 fecal samples from children with AGE, collected during a surveillance study carried out in a low-income community in Belém, Pará, between 1990 and 1992. METHODS: HAdV was detected by nested PCR, using primers Hex1deg/Hex2deg and NeHex3deg/NeHex4deg. SaV was assayed by reverse transcription PCR (RT-PCR), nested PCR, and quantitative PCR. The nucleotide sequence was determined by direct cycle sequencing. RESULTS: Overall, 43% (74/172) of samples were positive for HAdV, of which 70.3% (52/74) were sequenced and classified as belonging to five different species, mostly A and F. For SaV, positivity was 5.2% (9/172) and genotypes GI.1, GI.7, GII.1, and GV.2 were detected. CONCLUSIONS: The present results reinforce the need for further studies to obtain epidemiological data about the circulation of these viruses in Brazil, especially in the Amazon Region, where data from the early 1990's are scarce. Furthermore, the study describes for the first time the detection of SaV genotypes GI.7 and GV.2 in Brazil, showing that these types circulated in the region more than 25 years ago.


Assuntos
Adenovírus Humanos/isolamento & purificação , Gastroenterite/virologia , Genótipo , Sapovirus/isolamento & purificação , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , Distribuição por Idade , Sequência de Bases , Brasil/epidemiologia , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Pré-Escolar , Feminino , Gastroenterite/enzimologia , Genes Virais , Técnicas de Genotipagem/métodos , Humanos , Lactente , Recém-Nascido , Masculino , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Estudos Prospectivos , Sapovirus/genética , Fatores de Tempo
6.
Rev. Soc. Bras. Med. Trop ; 50(5): 621-628, Sept.-Oct. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-897017

RESUMO

Abstract INTRODUCTION: Acute gastroenteritis (AGE) is one of the most common causes of morbidity and mortality, especially among children from developing countries. Human adenovirus (HAdV) and sapovirus (SaV) are among the agents that cause AGE. The present study aimed to detect and genotype HAdV and SaV in 172 fecal samples from children with AGE, collected during a surveillance study carried out in a low-income community in Belém, Pará, between 1990 and 1992. METHODS: HAdV was detected by nested PCR, using primers Hex1deg/Hex2deg and NeHex3deg/NeHex4deg. SaV was assayed by reverse transcription PCR (RT-PCR), nested PCR, and quantitative PCR. The nucleotide sequence was determined by direct cycle sequencing. RESULTS: Overall, 43% (74/172) of samples were positive for HAdV, of which 70.3% (52/74) were sequenced and classified as belonging to five different species, mostly A and F. For SaV, positivity was 5.2% (9/172) and genotypes GI.1, GI.7, GII.1, and GV.2 were detected. CONCLUSIONS: The present results reinforce the need for further studies to obtain epidemiological data about the circulation of these viruses in Brazil, especially in the Amazon Region, where data from the early 1990's are scarce. Furthermore, the study describes for the first time the detection of SaV genotypes GI.7 and GV.2 in Brazil, showing that these types circulated in the region more than 25 years ago.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Brasil/epidemiologia , Adenovírus Humanos/isolamento & purificação , Infecções por Caliciviridae/virologia , Sapovirus/isolamento & purificação , Gastroenterite/virologia , Genótipo , Filogenia , Fatores de Tempo , Sequência de Bases , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , Reação em Cadeia da Polimerase , Prevalência , Estudos Prospectivos , Distribuição por Idade , Infecções por Caliciviridae/epidemiologia , Sapovirus/genética , Técnicas de Genotipagem/métodos , Gastroenterite/enzimologia , Genes Virais
7.
J Med Virol ; 89(9): 1539-1549, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28370221

RESUMO

Fecal specimens were collected during a longitudinal, community-based study in the city of Belém, North Brazil, that was conducted over 3 years (October 1982 to March 1986), in which 20 children were included from birth to 3 years of age. A total of 229 fecal samples were screened by real time RT-PCR targeting the junction region (ORF 1/2) of the norovirus (NoV) genome. NoV-positive samples were subjected to PCR and sequencing of the viral polymerase (ORF1) and viral protein 1 (VP1) genes (ORF2). The junction region was also sequenced to assess for recombination when ORF1 and ORF2 genotyping results were dissimilar. Samples classified as GII.P4/GII.4 were further characterized by sequencing the P2 subdomain of the viral capsid to determine possible alterations. An overall positivity of 16.1% (37/229) was observed, including GI (16.2%-6/37) and GII (83.8%-31/37) genogroups. Cases of NoV reinfection in at least 2-month intervals were observed, and 12 children developed at least one case of asymptomatic NoV infection. In total, 48.6% (18/37) NoV-positive samples were subjected to nucleotide sequencing analysis targeting the following polymerase genes: GI.P3 (n = 1), GII.Pa (n = 1), GII.Pc (n = 1), GII.P4 (n = 5), GII.P6 (n = 5), GII.P7 (n = 3), GII.P12 (n = 1), and GII.P22 (n = 1). For the VP1 gene, characterization was performed in 14 (77.8%) samples: GI.3 (n = 1), GII.2 (n = 1), GII.4 (n = 4), GII.6 (n = 4), GII.7 (n = 1), GII.12 (n = 1), GII.14 (n = 1), and GII.23 (n = 1). Recombination events were confirmed in three cases (GII.P12/GII.2, GII.P7/GII.14, and GII.Pa/GII.12), and four samples genotyped as GII.P4/GII.4 were analyzed to identify variants. None had contemporary counterparts. Three children developed consecutive NoV infections by different genotypes. The present report documents the importance of NoV as a cause of childhood infection during a longitudinal study conducted more than 30 years ago.


Assuntos
Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Genótipo , Norovirus/classificação , Norovirus/genética , Brasil/epidemiologia , Pré-Escolar , Fezes/virologia , Feminino , Técnicas de Genotipagem , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Epidemiologia Molecular , Norovirus/isolamento & purificação , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Proteínas Virais/genética
8.
J Med Virol ; 89(11): 1894-1903, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28321885

RESUMO

Fecal specimens were collected during a longitudinal, community-based study in the city of Belém, North Brazil, that was conducted over 3 years (October 1982 to March 1986), in which 20 children were included from birth to 3 years of age. A total of 229 fecal samples were screened by real time RT-PCR targeting the junction region (ORF 1/2) of the norovirus (NoV) genome. NoV-positive samples were subjected to PCR and sequencing of the viral polymerase (ORF1) and viral protein 1 (VP1) genes (ORF2). The junction region was also sequenced to assess for recombination when ORF1 and ORF2 genotyping results were dissimilar. Samples classified as GII.P4/GII.4 were further characterized by sequencing the P2 subdomain of the viral capsid to determine possible alterations. An overall positivity of 16.1% (37/229) was observed, including GI (16.2%-6/37) and GII (83.8%-31/37) genogroups. Cases of NoV reinfection in at least 2-month intervals were observed, and 12 children developed at least one case of asymptomatic NoV infection. In total, 48.6% (18/37) NoV-positive samples were subjected to nucleotide sequencing analysis targeting the following polymerase genes: GI.P3 (n = 1), GII.Pa (n = 1), GII.Pc (n = 1), GII.P4 (n = 5), GII.P6 (n = 5), GII.P7 (n = 3), GII.P12 (n = 1), and GII.P22 (n = 1). For the VP1 gene, characterization was performed in 14 (77.8%) samples: GI.3 (n = 1), GII.2 (n = 1), GII.4 (n = 4), GII.6 (n = 4), GII.7 (n = 1), GII.12 (n = 1), GII.14 (n = 1), and GII.23 (n = 1). Recombination events were confirmed in three cases (GII.P12/GII.2, GII.P7/GII.14, and GII.Pa/GII.12), and four samples genotyped as GII.P4/GII.4 were analyzed to identify variants. None had contemporary counterparts. Three children developed consecutive NoV infections by different genotypes. The present report documents the importance of NoV as a cause of childhood infection during a longitudinal study conducted more than 30 years ago.


Assuntos
Infecções por Caliciviridae/virologia , Fezes/virologia , Gastroenterite/virologia , Norovirus/genética , Brasil/epidemiologia , Infecções por Caliciviridae/epidemiologia , Proteínas do Capsídeo/genética , Pré-Escolar , Feminino , Gastroenterite/epidemiologia , Variação Genética , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Norovirus/classificação , Norovirus/isolamento & purificação , Fases de Leitura Aberta , Filogenia , Saúde Pública , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Recombinação Genética
9.
Braz. j. microbiol ; 47(3): 724-730, July-Sept. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-788955

RESUMO

ABSTRACT Gastroenteritis is one of the most common diseases during childhood, with norovirus (NoV) and sapovirus (SaV) being two of its main causes. This study reports for the first time the incidence of these viruses in hospitalized children with and without gastroenteritis in São Luís, Maranhão. A total of 136 fecal samples were tested by enzyme immunoassays (EIA) for the detection of NoV and by reverse transcription-polymerase chain reaction (RT-PCR) for detection of both NoV and SaV. Positive samples for both agents were subjected to sequencing. The overall frequency of NoV as detected by EIA and RT-PCR was 17.6% (24/136) and 32.6% (15/46), respectively in diarrheic patients and 10.0% (9/90) in non-diarrheic patients (p < 0.01). Of the diarrheic patients, 17% had fever, vomiting and anorexia, and 13% developed fever, vomiting and abdominal pain. Of the 24 NoV-positive samples, 50% (12/24) were sequenced and classified as genotypes GII.3 (n = 1), GII.4 (6), GII.5 (1), GII.7 (2), GII.12 (1) and GII.16 (1). SaV frequency was 9.8% (11/112), with 22.6% (7/31) in diarrheic patients and 4.9% (4/81) in nondiarrheic (p = 0.04) ones. In diarrheic cases, 27.3% had fever, vomiting and anorexia, whereas 18.2% had fever, anorexia and abdominal pain. One SaV-positive sample was sequenced and classified as GII.1. These results show a high genetic diversity of NoV and higher prevalence of NoV compared to SaV. Our data highlight the importance of NoV and SaV as enteropathogens in São Luís, Maranhão.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , História do Século XX , Adulto Jovem , Caliciviridae/classificação , Infecção Hospitalar , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Filogenia , Brasil , Caliciviridae/genética , Incidência , Infecções por Caliciviridae/diagnóstico , Infecções por Caliciviridae/história , Evolução Molecular , Norovirus/classificação , Norovirus/genética , Sapovirus/classificação , Sapovirus/genética , Gastroenterite/história , Gastroenterite/epidemiologia , Gastroenterite/virologia , Genótipo
10.
Infect Genet Evol ; 44: 361-366, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27476607

RESUMO

Recently, there has been an increase in the number of children hospitalized due to norovirus infection in Brazil. This is due both to the occurrence of more severe norovirus-related gastroenteritis cases after the introduction of the rotavirus vaccine and an increase in the tools for the detection of the disease. This pathogen is transmitted by the fecal-oral route, and the illness is characterized by diarrhea, vomiting, nausea and abdominal cramps. The genome of the virus is organized into three open reading frames showing strong mutation rates. Additionally, homologous recombination events, which can increase the virulence of the virus and lead to genotyping mistakes in molecular epidemiological studies, frequently occur. The purpose of this study was to describe two recombination events among different GII.4 variants that infected children who were hospitalized for severe acute gastroenteritis during distinct periods of time in Belém, Brazil. The recombination among the variants US95_96/Kaiso_2003 and Den Haag_2006b/Yerseke_2006a were observed in May 2003 and February 2009, respectively. In both cases, the association between the dominant variant at that point in time and another that was circulating at a low frequency in the population of Belém was demonstrated. Interestingly, the position of the breakpoint of the recombination event in the genome was the polymerase gene and was located at the nucleotide positions 4.834 and 5.002, which is an unusual location for the occurrence of recombination as other studies have previously reported the junction region as a breakpoint. In this study, both recombinant variant strains were related to severe cases of diarrhea that lead to hospitalization, demonstrating the viral evolution of GII.4 in response to selective pressures, which ultimately lead to the emergence of novel viral types in the pediatric population. The cases discussed here reinforce the need for continuous norovirus surveillance. To our knowledge, these two GII.4 variant recombinations have not yet been previously described.


Assuntos
Infecções por Caliciviridae/virologia , Gastroenterite/virologia , Variação Genética , Genótipo , Norovirus/genética , Recombinação Genética , Brasil/epidemiologia , Infecções por Caliciviridae/epidemiologia , Pré-Escolar , Fezes/virologia , Gastroenterite/epidemiologia , Humanos , Lactente , Fases de Leitura Aberta , Filogenia , RNA Viral/genética
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