The Food and Drug Administration announced that it has launched an investigation at Bakersfield, California-based produce supplier Thomson International to "learn more about" the potential source of contamination linked to the Salmonella Newport outbreak that has led to a nationwide recall of several onion brands.
The agency noted the investigation is ongoing and that additional information will be provided as it becomes available.
"Following the recall from Thomson International, Inc., additional products containing recalled onions have been identified and recalled," the FDA added.
The recall, issued by Thomson on Aug. 1, includes red, yellow, white and sweet yellow onions which were shipped beginning May 1 in cartons weighing between five and 50 pounds, and mesh sacks between two and 50 pounds. The recall covers onions sold under brand names including Thomson Premium; TLC Thomson International; Tender Loving Care; El Competitor; Hartley's Best; Onions 52; Majestic; Imperial Fresh; Kroger; Utah Onions; and Food Lion.
Supermarket chains Giant Eagle and Publix immediately issued their own recalls the same day. Giant Eagle has recalled onions and foods made with recalled onions sold in stores across Pennsylvania, Ohio, West Virginia, Indiana and Maryland, while Publix has recalled onions sold in bulk at stores in Alabama, Georgia, North Carolina, South Carolina, Tennessee and Virginia.
According to the U.S. Centers for Disease Control and Prevention, at least 640 people have been infected in 43 states.
The agency said that the illnesses started between June 19 and July 23, 2020, in people ranging from less than 1 to 102 years old, with a median age of 39. As of Friday, no deaths had been reported.
The CDC noted that some illnesses may have not yet been reported due to the time it takes between when a person becomes ill and when the illness is reported, which normally takes an average of two to four weeks.
The agency has identified twenty-five illness clusters in nine states. Illness clusters are defined as "two or more people who do not live in the same household who report eating at the same restaurant location, attending a common event, or shopping at the same location of a grocery store in the week before becoming ill."
"Information from these clusters shows that many ill people ate red onions. The traceback information collected from these illness clusters identified Thomson International, Inc., of Bakersfield, Calif., as a likely source of red onions," the CDC said. "Due to the way onions are grown and harvested, other onion types, such as, white, yellow, or sweet yellow, may also be contaminated. Additional traceback is ongoing to determine if other onions are linked to the outbreak."