Genetic characterization of rotavirus in children in South Korea from 2007 to 2009.

Rotavirus is the most important etiological agent in children with acute gastroenteritis (AGE). The recent implementation of a rotavirus vaccine in Korea requires the monitoring of prevailing rotavirus strains in order to control the infection. One hundred thirty-nine rotavirus strains were detected in children hospitalized with AGE in Seoul, Korea from 2007 to 2009. The most frequent combination of genotypes was G9P[8] (32.1%), followed by G1P[8] (20.7%) and G3P[8] (11.7%). Mixed G-types were detected in 14 samples (10.0%), and mixed P-types were found in six samples (4.3%). G9 genotypes were predominant from 2007 to 2008, whereas G1 and G3 genotypes were predominant from 2008 to 2009. G1 strains clustered mostly in the Id lineage, and some clustered in the Ic, IId, and Ia lineages. G2 strains clustered in the IV and V lineages. G3 and G9 strains clustered in the IIId and Id lineages, respectively. This study shows a rapid change of the prevalent genotype from G9 to G1 and G3 genotypes, suggesting that continuous surveillance of rotavirus strains is important for rotavirus vaccination.