One person has died and 22 others have been hospitalized due to a mysterious outbreak of listeria, the U.S. Centers for Disease Control and Prevention said Thursday. The CDC has asked the public to help it figure out what may be causing the spate of illnesses in 10 states but have homed in on Florida as a potential source of the outbreak.
Almost all of the 23 people sickened either live in Florida or have traveled to the state in the month before they became ill, but investigators have yet to determine what food may have spread the bacteria over a span of 18 months.
Listeria is a potentially deadly form of bacteria that can cause fever, vomiting and diarrhea. Symptoms generally start within two weeks of eating contaminated food, and illnesses can be severe for pregnant women, older adults and those with compromised immune systems.
Cases can be treated with antibiotics.
The one death was reported in Illinois, and the CDC noted five people were sickened while pregnant. One illness resulted in a fetal loss, the agency said.
“A specific food item has not yet been identified as the source of this outbreak,” the CDC said, noting the illnesses started on dates ranging from Jan. 24, 2021, through June 12, 2022. “Most of the sick people in this outbreak live in or traveled to Florida about a month before they got sick.”
The CDC added the true number of sick people is likely higher than the number reported as some people recover without medical care. It also takes three to four weeks to link an illness to an outbreak, so recent cases of listeriosis may not be reported in the data.
The agency has asked the public to help investigators determine the source of the outbreak, asking those with symptoms of listeria to write down as much as they can remember about what they’ve eaten in the month before they got sick.
Listeria can be found in contaminated foods including soft cheeses made with unpasteurized milk, raw vegetables, melons and some processed meats, such as hot dogs and cold cuts.