Fecal shedding of virus in relation to the days of illness in infantile gastroenteritis due to calicivirus.

Fecal shedding of virus in relation to the days of illness was studied by electron microscopic examinations of stool specimens collected during two consecutive outbreaks of gastroenteritis associated with calicivirus in an orphanage in the city of Sapporo, Japan. Of 61 stool specimens examined, 29 (48%) were found to contain typical calicivirus particles. Although caliciviruses were found in none of the seven stools obtained by chance before the onset of illness, they were found in 18 (95%) of 19 stool specimens collected within four days after the onset of illness. Seven (50%) of 14 specimens collected during the next five days were virus-positive, and the viruses were rarely detected in the stools collected thereafter. Thus correlation between viral shedding and the days of illness was clearly demonstrated. This finding should provide additional evidence for the etiologic role of calicivirus in acute infantile gastroenteritis.