Prevalence and Clinical Characteristics of Norovirus Gastroenteritis Among Hospitalized Children in Spain

Background: The importance of norovirus as a cause of gastroenteritis outbreaks is well documented, but the role of norovirus in sporadic acute severe gastroenteritis is not so well established. The aim of this study was to determine the prevalence and clinical characteristics of norovirus gastroenteritis among hospitalized children. Methods: A prospective study was conducted in children less than 5 years old, admitted with acute gastroenteritis between January 2005 and January 2008 to the Pediatrics Department of the Universitary Hospital, Albacete, Spain. Demographic and clinical data were collected. A stool sample from each child was screened for enteropathogenic bacteria and tested by reverse transcription polymerase chain reaction for rotavirus, astrovirus, norovirus, and sapovirus and by immunochromatographic method for enteric adeno-viruses. Results: Norovirus was the second most frequent pathogen after rotavirus, being detected in 61 (17.3%) of the 352 children enrolled, in 29 of them (8.2%) as single agent. Mixed infections involving other viruses or bacteria were present in 52.4% of norovirus positive samples, a nosocomial source of infection was demonstrated in 17.2%. Norovirus infection was more prevalent in winter and affected mainly children less than 2 years of age. Vomiting was present in 68% and fever in 48.3% of cases, 3 children had nonfebrile seizures. Compared with rotavirus enteritis, norovirus infection was slightly less severe (in terms of severity score and need of intravenous rehydration) and fever was less frequent. Conclusions: Norovirus was a frequent cause of acute severe sporadic gastroenteritis in children representing the second etiologic agent after rotavirus.