Short communicationHigh incidence of group A rotaviruses G4P[6] strains among children in Gyeonggi province of South Korea, from 2009 to 2012

•Globally rare RVA G4P[6] strains were steadily circulating in South Korea.•RVA G4P[6] strains were predominant in South Korea between 2009 and 2012.•Most of the G4P[6] strains were isolated from children < 1 year of age.•Korean RVA strains, sub-lineage Ie(G4) and Ia(P[6]), have been circulating since 2000.•The increase of G4P[6] strains can be a problem for RVA infection in post-vaccine era.

The genotype distribution of group A rotaviruses (RVAs) circulating in Gyeonggi province, South Korea between 2009 and 2012 was investigated. A total of 2619 stool specimens from sporadic acute gastroenteritis cases and 117 acute gastroenteritis outbreaks were analyzed. Among them, RVAs were detected from 263 (10.0%) sporadic cases and 3 (2.6%) outbreaks. The G4P[6] strains predominated (29.7%), followed by G1P[8] (19.4%), G2P[4] (15.6%), G3P[8] (13.3%) and G9P[8] (6.5%) strain. Especially 96.2% of the genotype G4P[6] strains were isolated from children < 1 year of age. Phylogenetic analysis revealed that genotype G4P[6] strains were members of sub-lineage Ie(G4) and Ia(P[6]). Intensified monitoring of RVAs, especially G4P[6] strains among young children, is essential to control RVA infections.