Listeria outbreak that sickened 23 people tied to ice cream brand

close-up of a man's hands as he scoops a second scoop of ice cream into a waffle cone
(Image credit: We Are via Getty Images)

A Listeria outbreak that resulted in 22 hospitalizations and one death has been linked to an ice cream brand called Big Olaf Creamery, the Centers for Disease Control and Prevention (CDC) announced July 2.

Big Olaf Creamery, based in Sarasota, Florida, is voluntarily contacting stores to "recommend against selling their ice cream products," the CDC stated. These products are sold only in Florida. In addition, "consumers who have Big Olaf Creamery brand ice cream at home should throw away any remaining product," the CDC advised. 

Meanwhile, the CDC, U.S. Food and Drug Administration (FDA), Florida Department of Health, and public health and regulatory officials in several other states are continuing their investigations into the outbreak, in case other products might be involved. 

Listeria monocytogenes, a bacterium that can cause an infection called listeriosis, has slipped into ice cream and triggered similar outbreaks in the past; for example, Blue Bell ice cream was linked to a listeriosis outbreak in 2015 and Nestlé Drumsticks were tied to another in 2016. That said, ice cream isn't the only food at risk of L. monocytogenes exposure — contaminated cheeses, vegetables, fruits, hot dogs, poultry and seafood have also caused outbreaks in the U.S., according to the FDA

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The current outbreak has affected 23 people across 10 states, so far. The affected individuals fell ill between Jan. 24, 2021 and June 12, 2022, and 20 of the affected individuals reported living in or traveling to Florida in the month before they got sick. (Symptoms of listeriosis typically appear within two weeks of exposure, although they may appear within the same day or up to 10 weeks later, the CDC states.)

The CDC partnered with federal and state health officials to interview those affected by the outbreak and found that, of 17 people interviewed, 14, or 82%, reported eating ice cream in the month before their illness. Of 13 people who remembered details about what kind of ice cream they consumed, six reported eating Big Olaf Creamery brand ice cream or eating ice cream at locations that might have been supplied by Big Olaf Creamery. 

Based on the results of this investigation, the CDC issued a food safety alert for Big Olaf Creamery brand ice cream, but again, the search for other potentially contaminated products is ongoing.

L. monocytogenes can infect anyone, but the microbe poses the biggest risk to pregnant people, newborns, people ages 65 and older and people with weakened immune systems, the CDC states. Symptoms of listeriosis include fever, muscle aches, headaches, a stiff neck, confusion, loss of balance and convulsions, as well as common food poisoning symptoms, such as nausea, vomiting and diarrhea. 

In elderly and immunocompromised people, the bacteria can infect the bloodstream, causing sepsis, or can infect the brain, causing meningitis or encephalitis. Newborns with listeriosis can develop serious complications that require immediate treatment and can result in lifelong health issues or death; and in pregnant people, the infection can cause miscarriage, stillbirth and premature delivery. One pregnant individual in the current outbreak experienced "fetal loss" due to the infection, the CDC reported. 

"Until we learn more, CDC is advising people at higher risk for severe Listeria illness to contact their healthcare provider if they have any symptoms of a Listeria infection," the CDC website states. Listeriosis can be treated with antibiotics. 

"Healthcare providers should report listeriosis illnesses to their health department," the CDC states.

In a July 3 Facebook post that has since been removed, Big Olaf Creamery stated that "For now, it is only speculation as it is an ongoing investigation, our brand has not been confirmed to be linked to these cases, I am not sure why only Big Olaf is being mentioned and targeted," according to ABC7

"6 out of the 23 patients mentioned having consumed Big Olaf ice cream, but nothing has been proven. We have been cooperating with the Florida Department of Health, FDACS and the FDA as soon as we were informed about the situation. We have been transparent and have answered all their questions and provided them with all the information requested from us, as the health and well-being of the public is our first priority."

Big Olaf Creamery representatives were not immediately available for comment on Tuesday (July 5).

Originally published on Live Science. 

Nicoletta Lanese
Channel Editor, Health

Nicoletta Lanese is the health channel editor at Live Science and was previously a news editor and staff writer at the site. She holds a graduate certificate in science communication from UC Santa Cruz and degrees in neuroscience and dance from the University of Florida. Her work has appeared in The Scientist, Science News, the Mercury News, Mongabay and Stanford Medicine Magazine, among other outlets. Based in NYC, she also remains heavily involved in dance and performs in local choreographers' work.