Severity of acute gastroenteritis in infants infected by G1 or G9 rotaviruses

Background: Group A rotaviruses are the main viral causative agent of acute diarrhea, and cause considerable morbidity in children. G9 rotaviruses have recently emerged all over the world and are thought to give more severe symptoms because of a lack of previous exposure and the absence of maternal antibodies in patients. Objectives: To determine the clinical severity of G9 infections compared to G1 infections in hospitalized children. Study design: The prospective study was conducted from 2004 to 2007 in French children under 5 years old hospitalized for acute gastroenteritis. The rotaviruses were detected in stools by ELISA tests and genotyped by RT-PCR on the basis of their outer capsid proteins. The duration of hospitalization, the Vesikari clinical score, and the requirement for intravenous rehydration were compared. Results: The stools from 370 children were analyzed and 162 stools infected by G1 (n = 76) or G9 (n = 86) rotaviruses were analyzed. Age and gender distribution were similar in the two groups as was the mean duration of hospitalization (2.7 days). The Vesikari scores were 12.96 and 12.83 in G1P[8] and G9P[8] groups (p = 0.417), respectively, in which 55.3 and 53.5% of the children, respectively, were rehydrated with an intravenous line. Conclusions: No difference in severity was found between G1 and G9 rotavirus infections. Rigorous surveillance to monitor changes in the ecology of rotavirus infections is necessary, as emerging strains are more