By Dr. Carol Hoban
Faculty Member, School of Public Health, American Military University

According to the Centers for Disease Control and Prevention (CDC), approximately 1,600 people contract listeriosis each year from eating contaminated food and around 260 of them die. Listeriosis, which can lead to a serious infection and even death, is caused by the bacterium Listeria monocytogenes.

Listeriosis is more likely to affect persons over the age of 65 or those with a weakened immune system, pregnant women and newborns, the CDC adds.

It can take anywhere from one to four weeks after eating Listeria-contaminated food before symptoms of listeriosis appear and spread beyond the digestive system, which is known as invasive listeriosis.

Common symptoms associated with invasive listeriosis include fever, flu-like symptoms, headaches, stiff neck, mental confusion, loss of balance, muscle aches and even convulsions.

Recent Listeriosis Outbreak Was Linked to a Contaminated Slicer Machine

One of the more recent outbreaks of listeriorsis was potentially linked to a contaminated slicer used to cut deli meats and cheeses, which was improperly cleaned. People who purchased those products from a number of retail locations became ill. This is a reminder that persons susceptible to Listeria infection should be cautious when handling deli products or avoid them altogether.

Another recent incident involving the Listeria pathogen occurred in the manufacturing process of ice cream, as reported in an article in USA Today. During the Food and Drug Administration’s (FDA) inspection of 89 commercial ice cream makers’ facilities in 2016 and 2017, Listeria monocytogenes was found at 18 sites on non-food contact surfaces. The FDA ordered specific action at six of the locations and recommended voluntary action at 39, where it found “objectionable conditions or practices.”

The FDA noted that these inspections highlight the need for commercial ice cream makers to maintain clean facilities to ensure that their operations do not contain harmful bacteria.

In addition to ice cream, Listeria outbreaks have been linked to celery, cantaloupe, raw sprouts and soft cheeses. However, most people who eat these foods will not come down with listeriosis.

If you suspect that you may have eaten food contaminated with the bacterium, you should seek medical attention. A laboratory test can confirm if you have listeriosis and you can be treated with antibiotics to kill the infection.

About the Author

Dr. Hoban earned her Ph.D. in cellular molecular biology and physiology from Georgia State University in 2008. She earned her MPH degree in 1997 from the Rollins School of Public Health at Emory University. Dr. Hoban has worked in maternal and child health and vaccine-preventable diseases. She was the project director for the Pregnancy Risk Assessment Monitoring System (PRAMS) in Georgia for over six years and was also the project director for the Georgia Immunization Study for over seven years. Dr. Hoban has numerous published articles based on her work in both vaccine-preventable diseases and maternal and child health. She is also currently a peer reviewer for the Maternal and Child Health Journal.