Gastroenteritis Outbreaks Caused by a DS-1–like G1P Rotavirus Strain, Japan, 2012–2013 - Volume 20, Number 6—June 2014 - Emerging Infectious Disease journal - CDC
Volume 20, Number 6—June 2014
Gastroenteritis Outbreaks Caused by a DS-1–like G1P Rotavirus Strain, Japan, 2012–2013
Author affiliations: Osaka City Institute of Public Health and Environmental Sciences, Osaka, Japan
It is estimated that rotavirus A (RVA), the leading cause of severe gastroenteritis in children worldwide, causes >500,000 deaths among children each year, primarily in developing countries (1). Genes of viral protein (VP) 7 and VP4 form the basis of a dual classification system that defines the RVA G- and P-types, respectively. Five G-types (G1–4 and G9) and 3 P-types (P, P, and P) represent most of the G-P–combined RVA strains (2). RVAs are classified on the basis of a system that assigns a specific type to each of the 11 RNA gene segments, according to established nucleotide percentage cutoff values (3).
Two well-known RVA prototype strains are Wa (G1-P-I1-R1-C1-M1-A1-N1-T1-E1-H1) and DS-1 (G2-P-I2-R2-C2-M2-A2-N2-T2-E2-H2). RVAs G1P, G3P, G4P, and G9P are pure Wa genogroup members because they have a Wa-like constellation (Gx-P[x]-I1-R1-C1-M1-A1-N1-T1-E1-H1) composed of genotype 1 genes; G2P is a pure DS-1 genogroup member because it has a DS-1–like constellation (Gx-P[x]-I2-R2-C2-M2-A2-N2-T2-E2-H2) composed of genotype 2 genes (4). The segmented nature of RVA genomes enables them to undergo gene reassortment during co-infection in 1 cell, leading to the emergence of progeny viruses containing mixed segments from >2 different parental strains. However, some human RVA G/P-types have a purely Wa-like or a DS-1–like genome constellation. Mixed viruses are rarely detected and have a low prevalence, even if they emerge; thus, it is believed that mixed viruses may be less fit than parental strains and unable to compete with them (5).
We identified and characterized a prevalent genotype G1P RVA with genotype 2 genes. The RVA was detected during rotavirus gastroenteritis outbreaks in Japan.
Dr Yamamoto is a research scientist at Osaka City Institute of Public Health and Environmental Sciences. His research interests include the molecular biology and molecular epidemiology of gastroenteritis viruses.
We thank Niichiro Abe, Kaoru Goto, and Atsushi Hase for supporting our work. We are also grateful to Peter Gee for proofreading and commenting on the manuscript.
- Figure. Maximum-likelihood phylograms of the viral protein (VP) 7 (877 bp) (A), VP4 (656 bp) (B), and VP6 (1,132 bp) (C) regions of rotavirus A strains detected during outbreaks in Osaka...
- Table 1. Description of RVA–associated outbreaks in Osaka City, Japan, during 2009–2013
- Table 2. Nucleotide sequence identity of various RVA strains to RVA DS-1–like G1P strain HC12016, which was detected during an outbreak in Osaka City, Japan, 2012
Suggested citation for this article: Yamamoto SP, Kaida A, Kubo H, Iritani N. Gastroenteritis outbreaks caused by a DS-1–like G1P rotavirus strain, Japan, 2012–2013. Emerg Infect Dis. 2014 June [date cited]. http://dx.doi.org/10.3201/eid2006.131326