"As of February 26, 2026, two isolates from one lot of organic whole milk powder, collected and analyzed by FDA, have been shown by whole genome sequencing (WGS) analysis to match a cluster of isolates reported by FDA on January 23, 2026. These two new isolates were collected by FDA at Dairy Farmers of America, the processor for Organic West Milk, which supplies ByHeart."
"The detection of Clostridium botulinum in infant formula, or ingredients, is complex. To date, WGS analysis has identified 17 different strains of this bacterium in samples from patients, finished products, and ingredients. While these sample results add to the available evidence needed to investigate the root cause of this outbreak, due to the complexities of Clostridium botulinum and limited scientific evidence currently available, FDA has not yet determined a root cause(s)."Case Counts
Total Illnesses: 48
Confirmed cases: 28
Probable cases: 20
Hospitalizations: 48
Deaths: 0
Last Illness Onset: November 29, 2025
States with Cases: AZ, CA, ID, IL, KY, MA, MI, MN, NC, NJ, OR, PA, RI, TX, VA, WA, WI
Product Distribution: Online and nationwide (including Guam and Puerto Rico), and internationally
https://www.fda.gov/food/outbreaks-foodborne-illness/outbreak-investigation-infant-botulism-infant-formula-november-2025
Outbreak Investigation of Infant Botulism: Infant Formula (November 2025)
CDC declares this outbreak over. FDA’s investigation into the root cause is ongoing.
