I have litigated Listeria cases stemming from outbreaks traced to a variety of foods, such as cantaloupe, cheese, celery and milk. I am presently representing 44 victims and their families in the 2011 Jensen Farms Listeria cantaloupe outbreak. I have spent a lot of time with Listeria experts.  This is yet another part in our series where we have been updating our “About-Bug” sites.  Here it is on Listeria.

Listeria (pronounced liss-STEER-ē-uh) is a gram-positive rod-shaped bacterium that can grow under either anaerobic (without oxygen) or aerobic (with oxygen) conditions.  Of the six species of Listeria, only L. monocytogenes (pronounced maw-NO-site-aw-JUH-neez) causes disease in humans.  These bacteria multiply best at 86-98.6 degrees F (30-37 degrees C), but also multiply better than all other bacteria at refrigerator temperatures, something that allows temperature to be used as a means of differentiating Listeria from other contaminating bacteria.

Called an “opportunistic pathogen,” Listeria is noted to cause an estimated 2,600 cases per year of severe invasive illness.  Perhaps not surprisingly then, “foodborne illness caused by Listeria monocytogenes has raised significant public health concern in the United States, Europe, and other areas of the world.”  As one noted expert observed, summarizing the history of these bacteria and their significance for public health:

Although L. monocytogenes was recognized as an animal pathogen over 80 years ago, the first outbreak confirming an indirect transmission from animals to humans was reported only in 1983, in Canada’s Maritime provinces. In that outbreak, cabbages, stored in the cold over the winter, were contaminated with Listeria through exposure to infected sheep manure. A subsequent outbreak in California in 1985 confirmed the role of food in disseminating listeriosis. Since then Listeria has been implicated in many outbreaks of food-borne illness, most commonly from exposure to contaminated dairy products and prepared meat products, including turkey and deli meats, pâté, hot dogs and seafood and fish.

All About Listeria

An Introduction to Listeria Bacteria
The Incidence of Listeria Infections
The Prevalence of Listeria in Food and Elsewhere
Transmission of and Infection with Listeria
Risk Factors for Listeria Infection
Symptoms of Listeria Infection
Complications of Listeria Infection
Diagnosis of Listeria Infection
Treatment for Listeria Infection
Antimicrobial Resistance in Listeria Bacteria
The Economic Impact of Listeria Infections
Real Life Impacts of Listeria Infection
Preventing Listeria Infection
Outbreaks of Listeria Infection
Recalls for Listeria Contamination
Consumer Resources for Listeria

Again, as always, if you have any comments, please pass them along.