title: Norovirus diversity in diarrheic children from an African-descendant settlement in Belém, Northern Brazil.
abstract: Norovirus (NoV), sapovirus (SaV) and human astrovirus (HAstV) are viral pathogens that are associated with outbreaks and sporadic cases of gastroenteritis. However, little is known about the occurrence of these pathogens in relatively isolated communities, such as the remnants of African-descendant villages ("Quilombola"). The objective of this study was the frequency determination of these viruses in children under 10 years, with and without gastroenteritis, from a "Quilombola" Community, Northern Brazil. A total of 159 stool samples were obtained from April/2008 to July/2010 and tested by an enzyme immunoassay (EIA) and reverse transcription-polymerase chain reaction (RT-PCR) to detect NoV, SaV and HAstV, and further molecular characterization was performed. These viruses were detected only in the diarrheic group. NoV was the most frequent viral agent detected (19.7%-16/81), followed by SaV (2.5%-2/81) and HAstV (1.2%-1/81). Of the 16 NoV-positive samples, 14 were sequenced with primers targeting the B region of the polymerase (ORF1) and the D region of the capsid (ORF2). The results showed a broad genetic diversity of NoV, with 12 strains being classified as GII-4 (5-41.7%), GII-6 (3-25%), GII-7 (2-16.7%), GII-17 (1-8.3%) and GI-2 (1-8.3%), as based on the polymerase region; 12 samples were classified, based on the capsid region, as GII-4 (6-50%, being 3-2006b variant and 3-2010 variant), GII-6 (3-25%), GII-17 (2-16.7%) and GII-20 (1-8.3%). One NoV-strain showed dual genotype specificity, based on the polymerase and capsid region (GII-7/GII-20). This study provides, for the first time, epidemiological and molecular information on the circulation of NoV, SaV and HAstV in African-descendant communities in Northern Brazil and identifies NoV genotypes that were different from those detected previously in studies conducted in the urban area of Belém. It remains to be determined why a broader NoV diversity was observed in such a semi-isolated community.
authors: Universidade do Estado do Pará, Belém, Pará, Brazil.
authors: Glicélia Cruz
authors: GC
authors: Aragão
authors: Joana D'Arc Pereira
authors: JD
authors: Mascarenhas
authors: Jane Haruko Lima
authors: JH
authors: Kaiano
authors: Maria Silvia Sousa
authors: MS
authors: de Lucena
authors: Jones Anderson Monteiro
authors: JA
authors: Siqueira
authors: Túlio Machado
authors: TM
authors: Fumian
authors: Juliana das Mercês
authors: Jd
authors: Hernandez
authors: Consuelo Silva
authors: CS
authors: de Oliveira
authors: Darleise de Souza
authors: Dde S
authors: Oliveira
authors: Eliete da Cunha
authors: Eda C
authors: Araújo
authors: Luana da Silva
authors: Lda S
authors: Soares
authors: Alexandre Costa
authors: AC
authors: Linhares
authors: Yvone Benchimol
authors: YB
authors: Gabbay
mesh_terms: D000818:Animals; D044383:Black People / Q000706:statistics & numerical data*; D001938:Brazil / Q000208:ethnology; D002648:Child; D003967:Diarrhea / Q000150:complications / Q000208:ethnology* / Q000821:virology*; D004285:Dogs; D005243:Feces / Q000821:virology; D005759:Gastroenteritis / Q000150:complications / Q000208:ethnology / Q000821:virology; D014644:Genetic Variation; D006801:Humans; D001257:Mamastrovirus / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D029322:Norovirus / Q000235:genetics* / Q000302:isolation & purification* / Q000502:physiology; D029341:Sapovirus / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology