1784. Detection of Norovirus GII.4 Sydney 2012 in US Health Care Facilities as Early as April 2012
Session: Poster Abstract Session: Viral Infections; Pathogenesis and Epidemiology
Saturday, October 5, 2013
Room: The Moscone Center: Poster Hall C
Posters
  • Detection of Norovirus GII.4 Sydney 2012 in US Health Care Facilities as Early as April 2012.pdf (535.9 kB)
  • Background: Noroviruses (NoV) from genogroup II, genotype 4 (GII.4) strains have historically caused the majority of NoV outbreaks worldwide and are associated with increased hospitalization and mortality rates relative to other NoV genotypes. The emergence of the NoV GII.4 Sydney 2012 variant strain, first identified in Sydney Australia in March 2012, has now replaced GII.4 New Orleans 2009 as the predominant NoV strain and has been reported to be the cause of increased levels of NoV activity globally.  Genetic variations within newly emergent NoV strains supported the establishment of a regimented NoV surveillance program at our clinical reference laboratory.  Fecal specimens received from healthcare facilities throughout the US that were NoVGII positive with a laboratory-developed NoV real-time RT-PCR assay were further genetically characterized with DNA sequencing of the ORF2 gene. Sequence analysis revealed that our clinical reference laboratory received two specimens from different regions of the US, as early as April 2012 that contained the NoV GII.4 Sydney 2012 strain.

    Methods: Partial ORF2 gene sequence data were generated for 185 fecal specimens collected from 2011-2012 that had previously tested positive for NoVGII with a laboratory-developed NoV real-time RT-PCR assay.  These partial ORF2 sequence data were analyzed using the NoV Genotyping Tool 1.0 (NIPHE, MHW&S, Netherlands), and specimens identified as belonging to the NoV GII.4 Sydney 2012 subcluster were subjected to additional bi-directional sequencing to obtain quality sequence data for at least 85% of the ORF2 gene.  These sequences were then aligned with all available GII.4 sequences from GenBank using Geneious Pro 6.0.3, subjected to NCBI BLAST analysis, and confirmed to be GII.4 Sydney 2012 variants using the NoV Genotyping Tool 1.0.

    Results: Through genetic sequence analysis of the NoV ORF2 gene we were able to confirm that the NoV GII.4 Sydney 2012 strain was detected by our laboratory-developed NoV real-time RT-PCR assay in clinical fecal specimens obtained from US health care facilities as early as April 2012.

    Conclusion: To our knowledge, this appears to be the earliest identification of the NoV GII.4 Sydney 2012 strain circulating in the US.

    James Grantham, BS1, Subina Mehta, MS2, Ingrid Caton, MS1, Steve Kleiboeker, PhD1, Michelle Altrich, PhD1 and Jeff Hester, PhD1, (1)Viracor-IBT Laboratories, Lee's Summit, MO, (2)University of Kansas Medical Center, Kansas City, KS

    Disclosures:

    J. Grantham, Viracor-IBT Laboratories: Employee, Salary

    S. Mehta, Viracor-IBT Laboratories: Employee, Salary

    I. Caton, Viracor-IBT Laboratories: Employee, Salary

    S. Kleiboeker, Viracor-IBT Laboratories: Employee, Salary

    M. Altrich, Viracor-IBT Laboratories: Employee, Salary

    J. Hester, Viracor-IBT Laboratories: Employee, Salary

    Findings in the abstracts are embargoed until 12:01 a.m. PST, Oct. 2nd with the exception of research findings presented at the IDWeek press conferences.