Monday, August 1, 2016
America's Center - St. Louis
Salina Parveen, University of Maryland Eastern Shore, Princess Anne, MD
Joan Meredith, University of Maryland Eastern Shore, Princess Anne, MD
Joy Mudoh, University of Maryland Eastern Shore, Princess Anne, MD
Breann Hrechka, University of Maryland Eastern Shore, Princess Anne, MD
Sylvia Ossai, University of Maryland Eastern Shore, Princess Anne, MD
Jurgen Schwarz, University of Maryland Eastern Shore, Princess Anne, MD
Ar'Quette Grant, University of Maryland Eastern Shore, Princess Anne, MD
Anna C. S Porto-Fett, U.S. Department of Agriculture-ARS-ERRC, Wyndmoor, PA
Mykeshia McNorton, U.S. Department of Agriculture-ARS-ERRC, Wyndmoor, PA
Laura Stahler, U.S. Department of Agriculture-ARS-ERRC, Wyndmoor, PA
Bradley A. Shoyer, U.S. Department of Agriculture-ARS-ERRC, Wyndmoor, PA
T G Nagaraja, Kansas State University, Manhattan, KS
Pragathi Shridhar, Kansas State University, Manhattan, KS
David Renter, Kansas State University, Manhattan, KS
Rodney Moxley, University of Nebraska-Lincoln, Lincoln, NE
John Luchansky, U.S. Department of Agriculture-ARS-ERRC, Wyndmoor, PA
Introduction: Escherichia coli O157:H7 (ECOH) is a significant public health concern in many countries and associated with a broad spectrum of infections which range from mild diarrhea to hemorrhagic colitis and hemolytic uremic syndrome. Recently, recalls of several thousand pounds of ECOH
contaminated retail veal from across the U.S. have increased interest in the prevalence and pathogenic potential of this pathogen.
Purpose: Investigate the prevalence and pathogenic potential of ECOH isolated from retail veal in four states in the Mid-Atlantic region of the U.S.
Methods: Ground veal (n=372) and veal cutlets (n=250) were purchased at retail stores in Delaware (n=144), Maryland (n=155), Virginia (n=142) and Pennsylvania (n=181) over a 12-month period spanning 2014 and 2015. All samples were enriched and then screened for the presence of ECOH using the BAX System Real-Time PCR. The BAX-positive cultures were further analyzed by a culture-based protocol involving immuno-magnetic separation (IMS) and plating on Rainbow Agar (RA). Isolates were analyzed by PCR for the presence of stx1, stx2, intimin (eae), EHEC-hemolysin (ehx), O157 (rfbE), and H7 (fliC) genes. Subtypes of stx1 and stx2were identified by nucleotide sequencing.
Results: Three of 622 samples (0.2%) tested positive for ECOH by BAX: one each from MD (ground veal), DE (ground veal), and PA (veal cutlets). However, only the sample from DE tested positive by both BAX and IMS. Isolates (n=10) recovered from the DE sample tested positive by BAX for all 6 genes screened, whereas MD isolates (n=10) were positive for only the O157 gene. Isolates (n=10) from PA were negative for all genes. All O157 isolates were positive for either stx1a or stx2a.
Significance: These results suggest the prevalence of ECOH in retail veal is quite low and shed insight on the pathogenic potential of ECOH recovered from veal at retail establishments.
