Email updates

Keep up to date with the latest news and content from Virology Journal and BioMed Central.

Open Access Research

Epidemics of enterovirus infection in Chungnam Korea, 2008 and 2009

KyoungAh Baek1, SangGu Yeo2, BaeckHee Lee3, KwiSung Park1, JaeHyoung Song4, JeeSuk Yu5, InSoo Rheem6, JaeKyung Kim6, SeoYeon Hwang27, YoungJin Choi7, DooSung Cheon2* and JoonSoo Park89*

Author Affiliations

1 Department of Microbiology, Chungcheongnam-Do Institute of Health and Environmental Research, Daejeon, Korea

2 Divison of Enteric and Hepatitis viruses, National Institute of Health, Korea Center for Disease Control and Prevention, Seoul, Korea

3 JeongGene Pediatrics, Yeongi, Korea

4 Department of Herbal Resources, Professional Graduate School of Oriental Medicine, Wonkwang University, Iksan, Korea

5 Departments of Pediatrics, College of Medicine, Dankook University, Cheonan, Korea

6 Departments of Laboratory Medicine, College of Medicine, Dankook University, Cheonan, Korea

7 Department of Biology, College of Sciences, Kyunghee University, Seoul, Korea

8 Departments of Laboratory Medicine, College of Medicine, Soonchunhyang University, Cheonan, Korea

9 Departments of Pediatrics, College of Medicine, Soonchunhyang University, Cheonan, Korea

For all author emails, please log on.

Virology Journal 2011, 8:297  doi:10.1186/1743-422X-8-297

Published: 13 June 2011

Abstract

Previously, we explored the epidemic pattern and molecular characterization of enteroviruses isolated in Chungnam, Korea from 2005 to 2006. The present study extended these observations to 2008 and 2009. In this study, enteroviruses showed similar seasonal prevalent pattern from summer to fall and age distribution to previous investigation. The most prevalent month was July: 42.9% in 2008 and 31.9% in 2009. The highest rate of enterovirus-positive samples occurred in children < 1-year-old-age. Enterovirus-positive samples were subjected to sequence determination of the VP1 region, which resolved the isolated enteroviruses into 10 types in 2008 (coxsackievirus A4, A16, B1, B3, echovirus 6, 7, 9, 11, 16, and 30) and 8 types in 2009 (coxsackievirus A2, A4, A5, A16, B1, B5, echovirus 11, and enterovirus 71). The most prevalent enterovirus serotype in 2008 and 2009 was echovirus 30 and coxsackievirus B1, respectively, whereas echovirus 18 and echovirus 5 were the most prevalent types in 2005 and 2006, respectively. Comparison of coxsackievirus B1 and B5 of prevalent enterovirus type in Korea in 2009 with reference strains of each same serotype were conducted to genetic analysis by a phylogenetic tree. The sequences of coxsackievirus B1 strains segregated into four distinct clusters (A, B, C, and D) with some temporal and regional sub-clustering. Most of Korean coxsackievirus B1 strains in 2008 and 2009 were in cluster D, while only "Kor08-CVB1-001CN" was cluster C. The coxsackievirus B5 strains segregated in five distinct genetic groups (clusters A-E) were supported by high bootstrap values. The Korean strains isolated in 2001 belonged to cluster D, whereas Korean strains isolated in 2005 and 2009 belonged to cluster E. Comparison of the VP1 amino acid sequences of the Korean coxsackievirus B5 isolates with reference strains revealed amino acid sequence substitutions at nine amino acid sequences (532, 562, 570, 571, 576-578, 582, 583, and 585).