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Updated: Jul 7, 2026
15:16
Detection and Genogrouping of Noroviruses from Children's Stools By Taqman One-step RT-PCR
Published on: July 22, 2012
Multiple recombinant noroviruses in Japan.
Tung Gia Phan1, Shuichi Nishimura, Kumiko Sugita
1Department of Developmental Medical Sciences, Institute of International Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Clinical Laboratory
|February 9, 2008
Summary
Norovirus infections affected 10.1% of Japanese children with acute gastroenteritis. Genotype GII/3 was most common, with new recombinant strains emerging as leading causes.
Area of Science:
- Virology
- Public Health
- Pediatrics
Background:
- Acute gastroenteritis is a significant health concern in pediatric populations worldwide.
- Noroviruses are a leading cause of viral gastroenteritis outbreaks.
- Understanding norovirus epidemiology, including prevalent genotypes and emergence of new strains, is crucial for public health interventions.
Purpose of the Study:
- To investigate the prevalence and genetic diversity of noroviruses in sporadic pediatric acute gastroenteritis cases in Japan.
- To identify the predominant norovirus genotypes and analyze the origins and emergence of recombinant strains.
Main Methods:
- Collection of 417 fecal specimens from pediatric acute gastroenteritis cases in Japan (2005-2006).
- Detection of noroviruses using reverse transcription-polymerase chain reaction (RT-PCR).
- Genotyping and phylogenetic analysis of detected norovirus strains.
Main Results:
- Noroviruses were detected in 10.1% (44/417) of the tested fecal specimens.
- Genotype GII/3 was the most predominant (56.8%), followed by GII/4 (34%).
- Phylogenetic analysis revealed the emergence of multiple recombinant noroviruses, introduced from four continents, with "new variant" strains becoming the leading cause for the first time in Japan.
Conclusions:
- Noroviruses are a significant cause of acute gastroenteritis in Japanese children.
- The study highlights the emergence and co-circulation of multiple recombinant norovirus strains in Japan, indicating global introductions.
- Continuous molecular surveillance is essential to track the evolution and spread of norovirus variants.
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