Published Date: 2012-01-17 13:56:54
Subject: PRO/AH/EDR> E. coli EHEC, 2010 - USA: (MN) non-O157, venison kabob
Archive Number: 20120117.1013136
E. COLI EHEC, 2010 - USA: (MINNESOTA) NON-O157, VENISON KABOB
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
Date: Wed 18 Jan 2012
Source: MSNBC [edited]
A Minnesota high school science project that involved hunting and butchering deer, including a road-kill capture, and turning the meat into venison kabobs backfired when 29 students were sickened with a kind of _Escherichia coli_ food poisoning, investigators say.
The 2010 incident just now reported in the journal Emerging Infectious Diseases highlights the risks of _E. coli_ contamination, not just from factory-processed meat, but also from small, local providers [http://wwwnc.cdc.gov/eid/article/18/2/11-0855_article.htm].
Doctors first knew they had a problem in December 2010 when 2 kids from the same high school turned up at a Minnesota hospital with abdominal pain and bloody diarrhea. Fearing they had a food poisoning outbreak on their hands, they quickly called in the state's top-notch public health officials.
Both teens had taken part in a school environmental science and outdoor recreation class that involving hunting, shooting, and butchering 6 white-tailed deer, explained Joshua Rounds, the study's lead author and an epidemiologist with the Minnesota Department of Public Health. A 7th deer was harvested after being hit by a car, the report says. The deer were processed on school grounds and then grilled and eaten in class a few weeks before the students got sick.
Epidemiologists interviewed 117 kids in 5 class periods and found that 29 definitely had become ill, but not with _E. coli_ O157:H7, the strain commonly associated with foodborne illness from ground beef. Samples from the students and the deer meat turned up _E. coli_ O103:H2, which is part of a larger category of non-O157 Shiga toxin-producing _E. coli_ bugs, known as STECs.
People don't usually get sick from eating hunks or steaks of muscle meat, Rounds said. In this case, however, the meat had been skewered and cooked only to medium rare. The skewers had dragged contaminants from the meat's surface down to the center of the kabobs, which hadn't been cooked to a high enough temperature to kill the bacteria. Unless the entire hunk of meat is cooked to 165 deg F [74 deg C], there is a risk of food poisoning, Rounds said.
Another factor was hand washing when handling meat, or the lack of it, Rounds said. Not everyone in the class was as fastidious about cleaning their hands as they could have been. "If you think about high school males, they're probably not the best when it comes to food safety practices," he said. "So you can have cross-contamination." The case is a reminder, Rounds said, that all meat, no matter where it comes from, should be treated with careful precautions.
[byline: Linda Carroll]
[A HealthMap/ProMED-mail interactive map of Minnesota can be seen at http://healthmap.org/r/1Cfy.
The Emerging Infectious Diseases formal report on the interesting outbreak of EHEC O103 can be found at http://wwwnc.cdc.gov/eid/article/18/2/11-0855_article.htm.
The outbreak is interesting because of the vehicle (assuming that the transmission did not occur at the time of butchering, since in the case-control study, consuming undercooked or pink venison was the activity associated with illness). Most meat-associated outbreaks of EHEC occur from ground beef, which facilitates external contamination of the meat to be spread throughout the ground beef. However, mechanical blade tenderization (1) as well as injection of tenderizer into the meat (2) via a needle and skewering the meat as here can do likewise. Adequately cooking of the meat and good kitchen hygiene will prevent such outbreaks.
The school-based activity is reminiscent to me of a previous posting on ProMED-mail of a cluster of salmonellosis among students following dissection of owl pellets in the school cafeteria. FYI, the following is useful knowledge regarding what an owl pellet is:
Like all birds, owls have no teeth to chew their food. Their food is usually swallowed whole, or in large chunks. After an owl swallows a mouse, strong acids in the owl's stomach begin to digest the mouse's muscle and other soft parts. The owl can't digest the bones and fur that come along with the meal, so the owl's stomach forms these indigestible materials into tight packages called pellets. Several hours after a meal, an owl will regurgitate one of these pellets. The pellets, along with feathers and other remains, can be found under owl roosts.
1. Luchansky JB, Phebus RK, Thippareddi H, Call JE. Translocation of surface-inoculated _Escherichia coli_ O157:H7 into beef subprimals following blade tenderization. J Food Prot. 2008; 71(11): 2190-7; abstract available at http://www.ncbi.nlm.nih.gov/pubmed/19044260.
2. Graumann GH, Holley RA. Survival of _Escherichia coli_ O157:H7 in needle-tenderized dry cured Westphalian ham. Int J Food Microbiol. 2007; 118(2): 173-9; abstract available at http://www.ncbi.nlm.nih.gov/pubmed/17706824. - Mod.LL]