Symptomatic and asymptomatic infections of rotavirus, norovirus, and adenovirus among hospitalized children in Xi'an, China

Rotavirus (RV), norovirus (NoV), and adenovirus (AdV) have been reported as the common viral pathogens of acute gastroenteritis in children. To determine the prevalence of RV, NoV, and AdV infections among hospitalized children with and without symptoms of acute gastroenteritis, fecal specimens, and data on clinical symptoms were collected from 201 children with diarrhea and 53 children without diarrhea admitted to the Xi'an Children's Hospital in Xi'an, China between March 2009 and May 2010. RV, NoV, and AdV were identified in 68.7% (138/201), 20.4% (41/201), and 5.0% (10/201), respectively, of children with diarrhea. These three viruses were also detected in 13.2% (7/53), 35.9% (19/53), and 9.4% (6/53), respectively, of children without diarrhea. Diarrheal children infected with RV alone showed the average severity score of 6.5, statistically significant higher than the average score of 5.3 in children with unidentifiable viruses. GII.3 and GII.4 were the only two NoV genotypes identified, and the GII.4 sequences were genetically close to GII.4 2006b cluster. These findings highlight the importance of NoV as a causative agent of pediatric diarrhea after RV based on the clinical and epidemiological characteristics of NoV infection, and particularly convey information of asymptomatic infections of enteric viruses in young children.