Fecal Shedding of Virus in Relation to the Days of Illness in Infantile Gastroenteritis Due to Calicivirus

Abstract

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.

Human viral gastroenteritis

“…In Madeley and Cosgrove's first report, all but two children were 2 months old or younger. In other reports, patients were 2 to 20 and 1 to 27 months old in orphanage outbreaks (53,54); 1 to 18 months old in a mother-baby psychiatric unit (69); 6 weeks to 13 years, with a peak at 1 to 6 months old in a general hospitalized population (67); and 4 to 6 years old in a school outbreak (248). However, in one outbreak occurring in a residential home for the elderly, 18 affected residents were 77 to 102 years old, and the 32 affected staff members were 16 to 68 years old (70).…”

“…They can cause gastroenteritis in the general pediatric population (67,267,346) as well as outbreaks in institutions including schools (248), orphanages (53,54), a mother-baby psychiatric unit (69), and nosocomially in pediatric wards in hospitals (67,341). Sporadic cases have occurred in the United Kingdom, Norway, Australia, Canada, United States, India, and Bulgaria (68).…”

Comprehensive Review of Human Sapoviruses

“…Subclinical (asymptomatic) sapovirus infection was also detected (4,6,21,134,135,(213)(214)(215)(216). Quantitative PCR analysis revealed that asymptomatic individuals also shed sapovirus in the feces at levels comparable to those shed by individuals with gastroenteritis (182,183).…”

“…1) (1). Sapovirus particles were first detected in human diarrheic stool samples in 1976 in the United Kingdom using electron microscopy (EM) (2), and the virus was soon recognized as a new gastroenteritis pathogen (3)(4)(5)(6)(7)(8)(9)(10)(11). However, the prototype strain of the Sapovirus genus was from another outbreak in Sapporo, Japan, in 1982 (strain Hu/SaV/Sapporo/1982/JPN), because it has been studied extensively for sapovirus virological and genetic characteristics (10,(12)(13)(14).…”

“…Sapovirus shedding in feces may continue after symptoms disappear (1 to 4 weeks after onset of illness) (6,22,174,191). Sapovirus shedding levels in clinical stool specimens range from 1.32 ϫ 10 5 to 1.05 ϫ 10 11 genomic copies/gram of stool (80, 99, 101, 116, 117, 127-130, 174, 178, 181-183).…”