What is Infant Botulism?
Infant botulism is a rare but serious condition caused by the ingestion of Clostridium botulinum spores, which can grow in the intestines of infants (typically those under one year old) and produce a potent toxin. This condition usually occurs when infants consume contaminated foods, particularly honey, which is known to harbor spores. The spores can germinate in the immature gastrointestinal tract of infants, leading to toxin production and subsequent illness.
Symptoms – What to watch for
Symptoms of infant botulism typically appear between 12 to 36 hours after ingestion of the spores and may include:
• Constipation: Often the first sign, with stools that may become less frequent and harder.
• Weakness: A general lethargy or decreased muscle tone (hypotonia), often described as “floppy baby syndrome.”
• Poor Feeding: Difficulty feeding or sucking.
• Cranial Nerve Dysfunction: This can lead to symptoms such as:
– Weak cry or inadequate vocalization.
– Difficulty swallowing.
– Drooping eyelids or poor eye movement (ptosis).
• Respiratory Problems: In severe cases, difficulty breathing due to muscle weakness can occur.
• Weakness in Movement: Reduced ability to move arms and legs.
• Irritability or unusual crying.
Treatment
Hospitalization: Infants diagnosed with botulism often require hospitalization to monitor respiratory function and general health.
Supportive Care: Treatment primarily focuses on supportive measures such as:
• Nutritional support, often via intravenous fluids or feeding tubes if necessary.
• Monitoring and management of respiratory function; in some cases, mechanical ventilation may be required if breathing difficulties arise.
• Botulism Immune Globulin (BIG): In the United States, a specific treatment called BabyBIG (Botulism Immune Globulin) is administered to infants diagnosed with botulism. This treatment helps to neutralize the Botulinum toxin and can reduce the duration and severity of symptoms.
• Antibiotics: Antibiotics are not typically used for treating infant botulism as they do not affect the toxin once produced and can also promote toxin production by encouraging the growth of bacteria.
Long-Term Prognosis
The prognosis for infants with botulism is generally good, especially with early diagnosis and appropriate treatment. Most infants recover fully within a few weeks or months, but the recovery time can vary.
Recovery Time: Symptoms usually resolve over several weeks, but in some cases, full recovery can take months, especially regarding muscle strength and tone.
No Long-Term Disabilities: Most children do not experience long-term complications or disabilities if treated promptly and effectively.
Follow-Up: Regular follow-ups may be necessary.
The FDA and CDC, in collaboration with the California Department of Public Health (CDPH), Infant Botulism Treatment and Prevention Program (IBTPP), and other state and local partners, continue to investigate a multistate outbreak of infant botulism. Epidemiologic and laboratory analyses indicate that ByHeart Whole Nutrition infant formula is the source of this multistate outbreak of infant botulism.
Since the last update on December 10, 2025, reports of cases linked to this outbreak have slowed, and public health officials have not added any new cases to this investigation. Going forward, instead of weekly updates, CDC will provide updates on this outbreak investigation when new information becomes available. FDA will continue to provide investigational updates as needed.
All ByHeart infant formula products have been recalled, and these products should not be available for sale in stores or online. This includes all formula cans and single-serve “anywhere pack” sticks. On December 12, 2025, FDA sent warning letters to four major retailers for failing to remove recalled ByHeart infant formula from their store shelves despite being notified of the recall. On December 15, 2025, FDA issued a press releaseand reminded industry about its legal duties regarding food recalls under the Federal Food Drug and Cosmetic Act. FDA asked companies to follow best practices when carrying out recalls. This is especially important for recalls involving foods for infants and young children, who are among our most vulnerable populations.
Additional testing by ByHeart, FDA, CDC, and state partners is underway, and results are expected in the coming weeks. Positive sample results for finished product testing will be included and updated in the Sample Results section below.
FDA’s investigation is ongoing to determine the point of contamination. This advisory will be updated as information becomes available.
Case Count Map Provided by CDC
Case Counts
Total Illnesses: 51
Hospitalizations: 51
Deaths: 0
Last Illness Onset: December 1, 2025
States with Cases: AZ, CA, ID, IL, KY, MA, ME, MI, MN, NC, NJ, OH, OR, PA, RI, TX, VA, WA, WI
Product Distribution: Online and nationwide (including Guam and Puerto Rico), and internationally
Useful Links
- CDC Outbreak Advisory
- Infant Botulism Treatment and Prevention ProgramExternal Link Disclaimer
- ByHeart Expanded Recall Announcement
- Food Safety Tips for Retailers and Consumers During an Outbreak
- Food Safety Resources for Produce Shippers and Carriers During a Foodborne Illness Outbreak
- Who to Contact
- What is Botulism?