The CDC says a Salmonella outbreak linked to fresh onions appears to be over and the FDA says it has concluded it’s traceback investigation, which showed the onions came from Thomson International Inc. in California.

Canadian officials recently reported the outbreak on their side of the border was over, saying the same company’s onions were behind the illnesses. In total, 1,642 people were confirmed infected, with 1,012 in the United States and the rest in Canada.

In a news release the U.S. Food and Drug Administration reported that the “FDA’s traceback portion of the investigation is complete and has identified Thomson International, Inc. of Bakersfield, CA, as the likely source of potentially contaminated red onions.” However, the FDA’s outbreak update web page says “FDA’s traceback investigation is ongoing. . .” An FDA spokesman confirmed for Food Safety News that the investigation is over.

Initially only red onions were of concern, but Thomson recalled all of its onions, including red, yellow, white and sweet, because they are all packed and processed on the same equipment.

“Ninety-one percent of people reported eating onions or foods likely containing onions in the week before their illness started,” the CDC reports. “Most ill people reported eating more than one type of onion.”

There is some concern that some people may still have implicated onions in their homes because of the practice of chopping and freezing the vegetable. See the full list of recalled onions and foods for U.S. consumers.

People in 48 states were sickened in the outbreak, with at least 167 requiring hospitalization, according to outbreak update from the Centers for Disease Control and Prevention.

Illnesses started on dates ranging from June 19 to Sept. 11 . Ill people ranged in age from less than 1 to 102 years old. Of 705 ill people with information available, 167 people were hospitalized. No deaths were reported.

About Salmonella infections
Food contaminated with Salmonella bacteria does not usually look, smell, or taste spoiled. Anyone can become sick with a Salmonella infection. Infants, children, seniors, and people with weakened immune systems are at higher risk of serious illness because their immune systems are fragile, according to the CDC.

Anyone who has eaten any onions and developed symptoms of Salmonella infection should seek medical attention. Sick people should tell their doctors about the possible exposure to Salmonella bacteria because special tests are necessary to diagnose salmonellosis. Salmonella infection symptoms can mimic other illnesses, frequently leading to misdiagnosis.

Symptoms of Salmonella infection can include diarrhea, abdominal cramps, and fever within 12 to 72 hours after eating contaminated food. Otherwise, healthy adults are usually sick for four to seven days. In some cases, however, diarrhea may be so severe that patients require hospitalization.

Older adults, children, pregnant women, and people with weakened immune systems, such as cancer patients, are more likely to develop a severe illness and serious, sometimes life-threatening conditions.

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