Prevalence and genetic diversity of astroviruses in children with and without diarrhea in São Luís, Maranhão, Brazil
Mem. Inst. Oswaldo Cruz
; 100(7): 709-714, Nov. 2005. tab, graf
Article
in En
| LILACS
| ID: lil-419692
Responsible library:
BR1.1
RESUMO
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 percent 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 percent (15/184); of these, 11 percent (9/84) for symptomatic and 5 percent (5/99) for those without symptoms or signs. Sequence analysis of amplicons revealed that HAstV-1 genotype was the most prevalent, accounting for 60 percent of isolates. Genotypes 2, 3, 4, and 5 were also detected, as one single isolate (10 percent) 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.
Full text:
1
Collection:
01-internacional
Database:
LILACS
Main subject:
Mamastrovirus
/
Genetic Variation
/
Astroviridae Infections
/
Diarrhea, Infantile
/
Gastroenteritis
Type of study:
Observational_studies
/
Prevalence_studies
/
Risk_factors_studies
Limits:
Child, preschool
/
Female
/
Humans
/
Infant
/
Male
/
Newborn
Country/Region as subject:
America do sul
/
Brasil
Language:
En
Journal:
Mem. Inst. Oswaldo Cruz
Journal subject:
MEDICINA TROPICAL
/
PARASITOLOGIA
Year:
2005
Document type:
Article
Affiliation country:
Brazil
Country of publication:
Brazil