Federal officials have declared that a deadly outbreak of listeria linked to Dole packaged salads has ended.
The Centers for Disease Control and Prevention announced Monday that the outbreak that left three people dead and at least 18 others sick across 13 states "is over." However, the CDC noted the number of sick people reported does not necessarily represent the total number of those who may have been infected as a result of the outbreak because some people recover without medical care and are not tested for the bacteria.
The outbreak strain of listeria started causing illnesses as far back as 2014, according to the CDC. Additional outbreaks in 2019 and 2020 were investigated but authorities were unable to gather enough data to identify the source at the time.
After additional cases were reported starting in August 2021, the CDC reopened the investigation in November. State and local public health officials who interviewed people, or their family, about the foods they ate in the month before they got sick learned that nine out of 10 reported eating packaged salads. Of the three people who remembered a specific brand, two reported Dole and one reported Little Salad Bar.
The CDC and Michigan Department of Agriculture and Rural Development collected samples of packaged salads from retail stores for testing and identified the outbreak strain of listeria in a Marketside brand package of shredded iceberg that was produced by Dole.
Dole found the outbreak strain on a piece of equipment at their Yuma, Arizona, facility and in December began voluntarily recalling salad bags and clamshells packaged there and in Bessemer City, North Carolina. The company expanded the recall in January 2022.
Those who became ill ranged in age from 50 to 94, according to the CDC. At least 16 people were hospitalized and three — in Michigan, Ohio and Wisconsin — died. The last illness was reported on Jan. 15, 2022.
Listeria symptoms usually start one to four weeks after eating contaminated food, but can start as soon as the same day.
Anyone with symptoms of listeriosis infection — which include fever, muscle aches, nausea, vomiting, diarrhea — are urged to contact their doctor. More severe cases could include symptoms like headache, stiff neck, confusion, loss of balance and convulsions.
People at a higher risk from a listeria infection include the elderly, people with weakened immune systems or chronic diseases, pregnant people and newborns.
Pregnant people with listeria typically experience only fever and other flu-like symptoms, like fatigue and muscle aches, but an infection can lead to miscarriage, stillbirth, premature delivery or complications after the baby is born.