1. View Salmonella Outbreak Slideshow Pictures
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3. Food Poisoning Slideshow Pictures

Medical Author:

Steven Doerr, MD

Steven Doerr, MD

Steven Doerr, MD, is a U.S. board-certified Emergency Medicine Physician. Dr. Doerr received his undergraduate degree in Spanish from the University of Colorado at Boulder. He graduated with his Medical Degree from the University Of Colorado Health Sciences Center in Denver, Colorado in 1998 and completed his residency training in Emergency Medicine from Denver Health Medical Center in Denver, Colorado in 2002, where he also served as Chief Resident.

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Medical Editor:

John P. Cunha, DO, FACOEP

John P. Cunha, DO, FACOEP

John P. Cunha, DO, is a U.S. board-certified Emergency Medicine Physician. Dr. Cunha's educational background includes a BS in Biology from Rutgers, the State University of New Jersey, and a DO from the Kansas City University of Medicine and Biosciences in Kansas City, MO. He completed residency training in Emergency Medicine at Newark Beth Israel Medical Center in Newark, New Jersey.

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Listeriosis is a disease caused by infection with a gram-positive, rod-shaped bacterium called Listeria monocytogenes.

• Listeria monocytogenes is ubiquitous, and it is usually found in soil, water, and decaying vegetation. Many farm animals and other domestic and wild animals can harbor the bacterium. Though many of these animals may be asymptomatic carriers of the bacterium, they can serve as a source to contaminate the foods produced from them, such as meat and dairy products. Listeria monocytogenes may also enter food-processing factories and contaminate food contact surfaces and non-food contact surfaces (for example, floors or drains).
• Listeria monocytogenes may contaminate various foods and dairy products, for example, raw vegetables and fruits, uncooked meats, packaged and processed meats (for example, hot dogs or deli meats), smoked seafood, soft cheeses, and unpasteurized milk/dairy products.
• Listeriosis is most often a food-borne illness that is transmitted to humans after they ingest foods or liquids contaminated with Listeria monocytogenes.
• Human-to-human transmission occurs when an infected pregnant mother transmits the infection to her fetus/newborn via the placenta or during delivery.
• In the United States, 2,500 cases of listeriosis are reported annually, with about 500 fatalities reported per year.
• In 2011, contaminated cantaloupes from a Colorado farm caused 146 cases of listeriosis with 32 fatalities, making it the deadliest food-borne illness outbreak in the United States since the early 1900s.