This illustration depicts a three-dimensional (3D) computer-generated image of a grouping of Listeria monocytogenes bacteria. The artistic recreation was based upon scanning electron microscopic (SEM) imagery.
What is listeria? (2015)
01:20 - Source: CNN

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CNN  — 

Here’s a look at listeriosis, a serious infection generally caused by eating food contaminated with the bacterium Listeria monocytogenes.

2001 - Listeriosis (infection with L. monocytogenes) is added to the Centers for Disease Control and Prevention’s (CDC) list of nationally notifiable diseases.

General Information

According to the CDC, 928 cases of listeriosis were reported in the United States in 2019.

Typically, Listeriosis affects older adults, pregnant women, infants and adults with compromised immune systems.

Pregnant women are approximately 10 times more likely to get listeriosis. Pregnant Hispanic women are 24 times more likely to get listeriosis than other people.

Listeria is named after Dr. Joseph Lister, an English surgeon who introduced sterilization into surgery. The mouthwash Listerine is also named after Dr. Lister.

Symptoms and Treatment

Symptoms include fever and muscle aches, and sometimes diarrhea or other gastrointestinal problems. Other symptoms are headache, confusion and convulsions.

Almost everyone diagnosed with listeriosis has an infection that has spread beyond the gastrointestinal tract.

Infections during pregnancy can lead to miscarriage, stillbirth, premature delivery or infection of the newborn.

Listeriosis can be treated with antibiotics.


General recommendations:
Thoroughly cook meat.
Clean raw fruits and vegetables thoroughly before eating.
Keep uncooked meats and poultry separate from vegetables and from cooked foods.
Do not drink unpasteurized milk or eat foods that contain unpasteurized milk.
Wash hands, utensils and countertops after handling uncooked foods.

Recommendations for persons at high risk:
Do not eat hot dogs, cold cuts, other deli meats, or fermented or dry sausages unless they are cooked properly.
Do not eat refrigerated meat spreads and pâtés.
Do not eat soft cheese unless it is labeled as made with pasteurized milk.
Do not eat refrigerated smoked seafood, unless it is in a cooked dish or it is canned.

Timeline of selected US cases

Turkey Deli Meat - 2002
Multistate outbreak of L. monocytogenes associated with turkey deli meat.

September 18, 2002 - The CDC announces that it is investigating an outbreak of listeriosis infections.

October 12, 2002 - Pilgrim’s Pride Foods, in Franconia, Pennsylvania, recalls 27.4 million pounds of fresh and frozen ready-to-eat turkey and chicken products produced since May 1, 2002. In total, 54 illnesses, eight deaths, and three fetal deaths are reported in nine states.

Cantaloupe - 2011
Multistate outbreak of listeria associated with cantaloupes.
All the tainted cantaloupes were grown at Jensen Farms in Granada, Colorado. They were shipped to 17 states. Cases of listeriosis were reported in Alabama, Arkansas, California, Colorado, Illinois, Indiana, Kansas, Maryland, Missouri, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, Texas, Virginia, West Virginia, Wisconsin and Wyoming. Health officials call it the deadliest food outbreak in the United States in nearly 100 years, and the third-deadliest outbreak in US history.

September 12, 2011 - The outbreak is announced by the CDC.

September 14, 2011 - The US Food and Drug Administration issues a press release to announce that Jensen Farms has issued a voluntary recall of its Rocky Ford-brand cantaloupes after being linked to a multistate outbreak of listeriosis. In total, 147 illnesses and 33 deaths are reported in 28 states.

September 26, 2013 - Eric and Ryan Jensen, brothers who own Jensen Farms, are taken into custody and charged with introducing tainted cantaloupe into interstate commerce.

October 22, 2013 -The Jensen brothers plead guilty to misdemeanor charges.

January 28, 2014 - They are sentenced to five years’ probation, including six months in home detention, for their role in the 2011 listeriosis outbreak.

Ricotta Cheese - 2012
September 10, 2012 - Multistate outbreak of listeriosis associated with Frescolina Marte Brand Ricotta Salata Cheese. Forever Cheese, Inc., initiates a voluntary recall of Frescolina Marte Brand Ricotta Salata Cheese with a single lot number. Four days later, Forever Cheese, Inc., expands the recall and removes all cheese related to the Italian exporter from the market.

In total, 22 illnesses and four deaths are reported in 13 states and the District of Columbia from the outbreak.

Caramel Apples - 2014
December 19, 2014 - The CDC announces it is investigating an outbreak of listeriosis linked to caramel apples.

January 6, 2015 - Bidart Bros. voluntarily recalls Granny Smith and Gala apples due to Listeria monocytogenes contamination at their apple-packing facility.

In total, 35 cases are reported in 12 states, with seven deaths.

Blue Bell - 2015
March 13, 2015 - The CDC announces it is working with the FDA to investigate an outbreak of listeriosis linked to Blue Bell Ice Cream. Blue Bell removes its product “Scoops” from the market.

March 23, 2015 - Blue Bell announces the recall of 3 oz. institutional/food service ice cream cups.

April 3, 2015 - Blue Bell announces it has suspended operations at its Oklahoma plant.

April 20, 2015 - Blue Bell voluntarily recalls all of their products on the market.

June 10, 2015 - The CDC says that the investigation is over. In all, 10 people in four states were infected and hospitalized, and three people died.

Vulto Creamery - 2017
March 9, 2017 - The CDC announces it is working with the FDA to investigate an outbreak of listeriosis linked to soft raw milk cheese made by Vulto Creamery in Walton, New York. Vulto Creamery has recalled all lots of Ouleout, Miranda, Heinennellie and Willowemoc soft raw milk cheeses.

May 3, 2017 - The CDC announces that the outbreak appears to be over. In total, eight cases, including two deaths, were reported in four states - Connecticut, Florida, New York, and Vermont.

Enoki Mushrooms - 2020
March 10, 2020 - The CDC announces it is working with the FDA to investigate a multistate outbreak of listeriosis linked to enoki mushrooms.