APHL 2018 Annual Meeting Poster Abstracts
Presenter: Colleen Courtney, PhD, Chief of Molecular Diagnostics,
DC Public Health Laboratory, Washington, DC, Phone:
202.481.3533, Email: [email protected]
Whole Genome Sequence Analysis of Salmonella
Montevideo Isolates from Multiple Outbreaks at
a Restaurant Between 1997 and 2012
J. Wolfe 1 , S. Klish, M. Zahn 1 , J. Sevinsky 3 , L. Fink 3 , M. Cheung 2 , M.
Crumpler 1 ; 1 Orange County Public Health Laboratory, Santa Ana,
CA, 2 Orange County Health Care Agency, Santa Ana, CA, 3 Colorado
Department of Public Health and Environment, Denver, CO
Background: Multiple outbreaks of Salmonella Montevideo
associated with a single restaurant located in Orange County, CA
occurred from 1997 to 2012. A total of 48 cases were identified,
including 30 patrons and 18 staff. Intense environmental
investigation in 2012 identified multiple sites at the facility with S.
Montevideo contamination. Pulsed-field gel electrophoresis (PFGE)
was performed on 30 patient and 10 environmental isolates. Eight
PFGE patterns with less than four band differences between them
were identified.
Results: The phylogenetic tree from lyve-SET hqSNP analysis
identified 4 clades, with none of the isolates differing from any other
by more than by 96 single-nucleotide polymorphisms (SNP). One
clade contained isolates from 2000, the other three clades were
from 2012 isolates. SNP differences between clades ranged from
13 to 68 SNPs.
Conclusions: The three clades from 2012 all contained case,
employee and environmental isolates, demonstrating that the
restaurant contained at least three separate strains. The 2000
clade contained isolates which differed from 2012 isolates by as few
as 13 SNPs, strongly suggesting that these Salmonella strains were
residing in the restaurant and caused outbreaks for over 15 years.
Molecular analysis of the case isolates alone may have suggested
that the 2012 clades were unrelated, but careful epidemiological
investigation clearly tied these clades together through employee
and environmental isolates.
Presenter: Julia Wolfe, MPH, Orange County Public Health
Laboratory, Santa Ana, CA, Phone: 714.834.8277, Email:
[email protected]
An Alternative to Liquid Handling Robots in Next-Generation
Sequencing: Streamlin