Forty-eight infants in 17 states across America were hospitalized with botulism after consuming ByHeart Whole Nutrition infant formula between late 2023 and early 2026 — the largest infant botulism outbreak ever documented in the United States. All 48 were treated with BabyBIG, the only available treatment for infant botulism. No infants died. The CDC and FDA declared the outbreak over on February 26, 2026, with no new cases reported since December 2025.
But the definitive answer to how Clostridium botulinum contaminated a commercially manufactured infant formula product — a contamination event that should be virtually impossible given the regulatory oversight applied to one of the most tightly controlled categories of food in America — remains officially undetermined. A June 10, 2026 investigation by Food Safety Magazine reveals that the FDA's completed inspections of ByHeart's facilities "did not identify any deficiencies that could explain the root cause of this outbreak" — even though whole-genome sequencing has confirmed a genetic match between C. botulinum isolated from patients, from ByHeart finished formula products, and from organic whole milk powder collected at Dairy Farmers of America, the processor for ByHeart's supplier Organic West Milk.
