Oct. 21, 2021 -- Federal officials have identified whole onions as the source of an ongoing, multistate outbreak of Salmonella Oranienburg, according to a CDC food safety alert released Wednesday.

One source linked to the infection is fresh red, white, and yellow onions imported from Chihuahua, Mexico, and distributed throughout the U.S. by ProSource Inc., the CDC says

So far, 652 people have reported an illness related to the outbreak in 37 states, and 129 people have been hospitalized. No deaths have been reported.

The CDC advises people who have unlabeled whole red, white, or yellow onions at home to not eat them and to throw them away. Businesses should also not serve or sell onions that were imported from Chihuahua or distributed by ProSource. People should wash and sanitize any surfaces that may have come into contact with the onions.

According to the CDC investigation details, the illness dates have ranged from May 31 to Sept. 30. Sick people ranged in age from less than 1 year to 97 years, with a median age of 37, and 57% are female.

During interviews, health officials found that 75% of sick people ate raw onions or dishes that contained raw onions. Several people reported eating at the same restaurants, which means they could be part of an illness cluster, the CDC said. States have identified 20 illness clusters at restaurants where onions were served.

One of the clusters was in a restaurant where investigators identified the outbreak strain in a condiment container with leftover lime and cilantro. The sick person reported that the cup also had onions, although none were left in the cup when it was tested.

After that, investigators found that ProSource supplied the whole onions to the restaurants where sick people ate, including the restaurant with the contaminated condiment cup. ProSource said the onions were last imported on Aug. 27, but these onions can last up to 3 months in storage and may still be in homes and businesses, the CDC said.

The investigation is still active, and officials are trying to find out if other onions or suppliers are linked to the outbreak. The highest number of cases have been identified in Texas and Oklahoma, according to a CDC map, though the outbreak ranges across the country.

The CDC advises people to contact a doctor if they have severe salmonella symptoms, which can include diarrhea for more than 3 days that doesn’t improve, bloody diarrhea, a fever higher than 102 Fahrenheit, frequent vomiting that prevents someone from absorbing liquids, and signs of dehydration such as infrequent urination and a dry mouth.

Most people infected with salmonella have diarrhea, fever, and stomach cramps from 6 hours to 6 days after eating contaminated food. The illness usually lasts 4 to 7 days, and most people recover without treatment.

But for some, the illness may become severe and require hospitalization. Salmonella infections may spread from the intestines to the blood and other parts of the body.

Children under age 5, adults over age 65, and people with weakened immune systems are more likely to have a severe illness.

The CDC also advises people to report foodborne illnesses to their local health department.

WebMD Health News Brief

Sources

CDC: “Salmonella Outbreak Linked to Onions: Food Safety Alert,” updated Oct. 20, 2021; “Salmonella Outbreak Linked to Onions: Investigation Details,” updated Oct. 20, 2021; “Salmonella Outbreak Linked to Onions: Where Sick People Lived,” updated Oct. 20, 2021; “How to Report a Foodborne Illness -- General Public.”

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