Prevalence and genetic diversity of astroviruses in children with and without diarrhea in São Luís, Maranhão, Brazil.

Autor: Gabbay YB; Seção de Virologia, Instituto Evandro Chagas, Secretaria de Vigilância em Saúde, Ministério da Saúde, 67030-000 Ananindeua, PA, Brazil. yvonegabbay@iec.pa.gov.br, Luz CR, Costa IV, Cavalcante-Pepino EL, Sousa MS, Oliveira KK, Wanzeller AL, Mascarenhas JD, Leite JP, Linhares AC
Jazyk: angličtina
Zdroj: Memorias do Instituto Oswaldo Cruz [Mem Inst Oswaldo Cruz] 2005 Nov; Vol. 100 (7), pp. 709-14. Date of Electronic Publication: 2006 Jan 09.
DOI: 10.1590/s0074-02762005000700004
Abstrakt: 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.
Databáze: MEDLINE