title: Prevalence and genetic diversity of astroviruses in children with and without diarrhea in São Luís, Maranhão, Brazil.
abstract: Human astroviruses (HAstV) have been increasingly identified as important etiological agents of acute gastroenteritis in children up to five years old. The aim of this study was to determine the prevalence and genotype diversity of HAstV in children with symptomatic and asymptomatic infections in São Luís, Maranhão, Brazil. From June 1997 to July 1999 a total of 183 fecal samples 84 from symptomatic and 99 from asymptomatic children were tested by enzyme immunoassay for HAstV. Prevalence rates were found to be 11 and 3% for symptomatic and asymptomatic children, respectively. Reverse transcription-polymerase chain reaction (RT-PCR) was carried out in 46 specimens (26 symptomatic and 20 asymptomatic) including the 12 samples that were positive by enzyme immunoassay (EIA). The overall positivity yielded by both methods was 8% (15/184); of these, 11% (9/84) for symptomatic and 5% (5/99) for those without symptoms or signs. Sequence analysis of amplicons revealed that HAstV-1 genotype was the most prevalent, accounting for 60% of isolates. Genotypes 2, 3, 4, and 5 were also detected, as one single isolate (10%) for each type. Variations in the sequences were observed when Brazilian isolates were compared to prototype strains identified in the United Kingdom. No seasonal pattern of occurrence was observed during these two years of study, and peak detection rate was observed in children aged between 3 and 6 months in the symptomatic group, and between 18 and 24 months in the controls.
authors.affiliation: Seção de Virologia, Instituto Evandro Chagas, Secretaria de Vigilância em Saúde, Ministério da Saúde, 67030-000 Ananindeua, PA, Brazil. yvonegabbay@iec.pa.gov.br
authors.forename: Yvone B
authors.initials: YB
authors.lastname: Gabbay
authors.forename: Cláudia Regina N E da
authors.initials: CR
authors.lastname: Luz
authors.forename: Ivete V
authors.initials: IV
authors.lastname: Costa
authors.forename: Elielma L
authors.initials: EL
authors.lastname: Cavalcante-Pepino
authors.forename: Maisa S
authors.initials: MS
authors.lastname: Sousa
authors.forename: Krynssya K
authors.initials: KK
authors.lastname: Oliveira
authors.forename: Ana Lucia Monteiro
authors.initials: AL
authors.lastname: Wanzeller
authors.forename: Joana D'Arc P
authors.initials: JD
authors.lastname: Mascarenhas
authors.forename: José Paulo G
authors.initials: JP
authors.lastname: Leite
authors.forename: Alexandre C
authors.initials: AC
authors.lastname: Linhares
mesh_terms: D000208:Acute Disease; D019350:Astroviridae Infections / Q000453:epidemiology*; D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D002675:Child, Preschool; D003968:Diarrhea, Infantile / Q000453:epidemiology / Q000821:virology*; D005243:Feces / Q000821:virology; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology / Q000821:virology*; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D001257:Mamastrovirus / Q000235:genetics / Q000302:isolation & purification; D010802:Phylogeny; D015995:Prevalence; D012367:RNA, Viral / Q000235:genetics
chemical_list: D012367:RNA, Viral