Astrovirus detection in sporadic cases of diarrhea among hospitalized and non-hospitalized children in Rio De Janeiro, Brazil, from 1998 to 2004

We analyzed 379 stool samples collected from January 1998 through December 2004, from hospitalized and non-hospitalized children with diarrhea in Rio de Janeiro, Brazil. These samples had prior negative results for other enteric viruses and bacterial pathogens. The specimens were analyzed for HAstV detection by RT-PCR. HAstV genotypes were determined by sequence analysis of the RT-PCR products. Twenty (5.3%) out of 379 samples were positive for astro-virus. Astrovirus was equally common among inpatients and outpatients and among different age groups. Of 20 HAstV-infected children, 13 (65%) were either hospitalized or received medical care in the emergence department, which suggests that they had a more severe illness. Only 7 (35%) of the 20 HAstV-infected children attended walk-in clinics, which suggests that they had mild disease. Other then diarrhea, fever was the most common symptom among the HAstV-positive patients, followed by vomit and bloody diarrhea. HAstV-1 was the predominant strain although genotypes 2 and 4 were also found. There was no obvious difference among HAstV strains detected from inpatients or outpatients or among different age groups. The study documented that astrovirus is an agent of acute diarrhea in children who are inpatients or outpatients in Rio de Janeiro, Brazil although it seems to be less common as a single cause of childhood diarrhea then rotavirus..