ByHeart Infant Formula and the 2025 Infant Botulism Outbreak
Table of Contents
In late 2025, the Centers for Disease Control and Prevention (CDC) investigated an outbreak of infant botulism linked to ByHeart infant formula, marking the first-ever outbreak of itS kind. As of January 23, 2026, the situation remains under inquiry, with no further widespread outbreaks reported beyond the initial cases linked to specific lots of ByHeart formula.
Initial Reports and CDC Response (November 2025)
The CDC was notified on November 7, 2025, by the Infant botulism Task Force (IBTPP) of a concerning increase in infant botulism cases associated with ByHeart formula consumption. The CDC’s investigation page details the timeline and findings. typically, the U.S. sees 150-180 cases of infant botulism annually; an outbreak is considered unprecedented. On November 8, 2025, the CDC urged parents to stop using two specific lots of ByHeart formula. By November 11, 2025, the CDC expanded the warning to include all ByHeart infant formula. The FDA’s investigation page provides further details on the agency’s involvement.
Infant Botulism: Definition and symptoms
Infant botulism is a rare but serious illness caused by the bacterium Clostridium botulinum, which produces a toxin that attacks the nervous system. The CDC defines infant botulism as occurring when infants ingest the bacteria, which than colonize the gut and produce the toxin. Symptoms include constipation, weak cry, poor feeding, lethargy, and decreased muscle tone. Thes symptoms can progress to paralysis and, in rare cases, respiratory failure. Early diagnosis and treatment with botulism antitoxin are crucial.
Investigation and Laboratory Testing
CDC laboratories are actively testing clinical samples from affected infants and samples from open containers of ByHeart formula collected from the homes of sick infants to identify the source of the contamination. The CDC’s outbreak investigation page provides updates on laboratory findings. The investigation focuses on determining how Clostridium botulinum spores entered the formula during the manufacturing process. As of January 23, 2026, the specific source of contamination has not been publicly identified, but the investigation is ongoing.
- Centers for Disease Control and Prevention (CDC): https://www.cdc.gov/
- U.S. Food and Drug Management (FDA): https://www.fda.gov/
- ByHeart, Inc.: https://www.byheart.com/
- Infant Botulism Task Force (IBTPP): https://www.cdc.gov/botulism/infant-botulism/ibtf.html
