Gastroenteritis Outbreaks Associated with the Emergence of the New GII.4 Sydney Norovirus Variant during the Epidemic of 2012/13 in Shenzhen City, China

PLoS One. 2016 Nov 9;11(11):e0165880. doi: 10.1371/journal.pone.0165880. eCollection 2016.

Abstract

Noroviruses (NoVs) are the leading cause of gastroenteritis outbreaks in humans worldwide. Since late 2012, a new GII.4 variant Sydney 2012 has caused a significant increase in NoV epidemics in several countries. From November of 2012 to January of 2013, three gastroenteritis outbreaks occurred in two social welfare homes (Outbreaks A and B) and a factory (Outbreak C) in Shenzhen city of China. Feces and swabs were collected for laboratory tests for causative agents. While no bacterial pathogen was identified, all three outbreaks were caused by NoVs with detection rates of 26.2% (16/61) at Outbreak A, 35.2% (38/108) at Outbreak B), and 59.3% (16/27) at Outbreaks C. For Outbreak B, 25 of the 29 symptomatic individuals (86.2%) and 13 of the 79 asymptomatic individuals (16.5%) were found NoV-positive. For Outbreak C, an asymptomatic food handler was NoV-positive. All thirteen NoV sequences from the three outbreaks were classified into genogroup II and genotype 4 (GII.4), which we identified to be the GII.4 Sydney 2012 variant. The genome of two isolates from Outbreaks A and B were recombinant with the opening reading frame (ORF) 1 of GII.4 Osaka 2007 and ORF2 and 3 of the GII.4 New Orleans. Our study indicated that the GII.4 Sydney 2012 variant emerged and caused the outbreaks in China.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Caliciviridae Infections / epidemiology
  • Caliciviridae Infections / virology*
  • Capsid Proteins / genetics
  • China / epidemiology
  • Disease Outbreaks
  • Epidemics
  • Feces / virology
  • Female
  • Gastroenteritis / virology*
  • Genetic Variation*
  • Genome, Viral / genetics
  • Genotype
  • Host-Pathogen Interactions
  • Humans
  • Male
  • Middle Aged
  • Norovirus / classification
  • Norovirus / genetics*
  • Norovirus / physiology*
  • Open Reading Frames / genetics
  • Phylogeny
  • Prevalence
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Analysis, DNA

Substances

  • Capsid Proteins

Grants and funding

The research was supported by The Key Project of Science and Technology (Grant No. 2012ZX10004215) funded by the Ministry of Science and Technology of China and the Health Industry Research (Grant No. 201302004) funded by National Health and Family Planning Commission of China to Miao Jin. The study was also supported by the National Natural Science foundation of China (Grant No. 81470856) to Yuanping Zhou. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.