The Centers for Disease Control and Prevention (CDC) has updated its investigation into an outbreak of infant botulism linked to ByHeart infant formula. Working with the California Department of Public Health's Infant Botulism Treatment and Prevention Program (IBTPP), CDC investigators have now identified 10 cases dating back to December 2023.
As of December 10, 2025, there have been 51 infants from 19 states hospitalized in connection with this outbreak. All affected infants received treatment with BabyBIG, and no deaths have been reported. Infant botulism occurs when babies ingest Clostridium botulinum spores that produce toxins in the gut. Early symptoms often include constipation, difficulty feeding, a weak or altered cry, and lack of head control.
The CDC continues to advise parents not to use any ByHeart Whole Nutrition infant formula. Laboratory tests confirmed that the product is contaminated with botulism spores capable of causing illness in infants.
The agency highlighted its rapid response after being notified by IBTPP on November 7, 2025, about an unusual increase in infant botulism cases among those consuming ByHeart formula. "While we typically expect to see 150-180 individual cases of infant botulism annually, an outbreak of infant botulism is unprecedented," said Dr. Jennifer Cope, chief of the Enteric Diseases Epidemiology Branch. That same evening, CDC and the U.S. Food and Drug Administration contacted ByHeart to urge removal of certain formula products from stores. On November 8, CDC issued a warning for all parents nationwide to stop using two lots of ByHeart formula and informed them about the outbreak.
By November 11, based on ongoing data review, CDC expanded its warning advising against use of any ByHeart infant formula. The agency’s laboratories are currently testing clinical samples from sick infants as well as open containers collected from their homes.
According to the CDC, this marks the first recorded outbreak of infant botulism associated with a commercial product. The agency emphasized its efforts in responding quickly during this health emergency: "Although this is the first ever outbreak of infant botulism, CDC experts used their rapid response skillset to act immediately to save the lives of infants in America and provide clear guidance to frightened parents during a health emergency."
The CDC plays a key role in protecting public health by providing timely information and responding rapidly to disease outbreaks across communities nationwide.
