• 37 confirmed U.S. cases; all powdered ByHeart formula recalled
• Botulism detected in unopened cans; international risk under review
• BabyBIG treatment effective but hard to access outside the U.S.
Federal health officials are urging families to check their pantries after 37 U.S. infants were diagnosed with infant botulism linked to ByHeart-brand powdered infant formula—an outbreak that has rapidly become one of the largest recorded in the United States. While all known cases remain domestic, the formula was shipped to 21 other countries, and public health authorities say it is still unclear whether infants overseas have also been affected.
Illnesses span 17 states with onset from August to November
The U.S. Food and Drug Administration (FDA) said in its Nov. 26 update that the cases occurred in 17 states, with symptoms beginning between Aug. 9 and Nov. 19, 2025. All 37 infants required hospitalization, though no deaths have been reported.
The investigation escalated after the discovery that unopened cans of ByHeart Whole Nutrition powdered infant formula contained botulinum toxin. In response, ByHeart issued a full recall of all its powdered formula products, citing the potential for serious harm.
BabyBIG treatment effective but restricted
In the U.S., treatment for infant botulism relies heavily on BabyBIG, a human-derived antibody product formally known as Botulism Immune Globulin Intravenous. BabyBIG is proven to reduce the duration and severity of illness and shorten hospital stays, but it is not widely accessible. It is not stocked by pharmacies and is available exclusively through the Infant Botulism Treatment and Prevention Program (IBTPP) operated by the California Department of Public Health.
Doctors must contact the program’s on-call physicians for approval and logistical coordination. While this system ensures proper oversight, it can delay treatment—an issue that becomes more serious in international settings.
BabyBIG has been licensed in the U.S. since 2003 and used abroad since 2005 on a case-by-case basis. But because it is not licensed internationally, its use depends on each country’s emergency approval process. Research shows that international patients experience longer delays due to customs clearance, transportation challenges, and requirements for laboratory confirmation before requests are approved. These delays are believed to contribute to longer hospitalizations.
Formula shipped globally but no confirmed foreign cases
ByHeart’s recalled products reached a wide range of markets, including Argentina, Brazil, Brunei, Canada, Chile, China, Colombia, Ecuador, Egypt, Hong Kong, Israel, Jamaica, Japan, South Korea, Peru, Philippines, Romania, Singapore, South Africa, Thailand, and the British Virgin Islands.
To date, none of these countries have reported confirmed infant botulism cases linked to ByHeart formula, but health agencies are monitoring for symptoms among infants who consumed the product. Many countries do not routinely test for infant botulism, complicating surveillance efforts.
What to know about infant botulism
Infant botulism is caused by ingestion of spores that germinate and release a potent neurotoxin in the intestines. Symptoms can progress from mild to life-threatening and typically include constipation, poor feeding, weak cry, low muscle tone, and respiratory difficulty. Early treatment dramatically improves outcomes.
While rare, infant botulism associated with commercial infant formula is considered a critical public health issue, and this outbreak is expected to prompt scrutiny of powdered formula manufacturing practices worldwide.
PREVENTION TIPS
How parents can reduce the risk of infant botulism
Avoid honey for children under 1 year old. Honey is a known source of spores.
Check all ByHeart powdered formula lot codes. Discard any recalled product immediately.
Practice strict bottle hygiene. Wash and sterilize bottles, nipples, and scoops daily.
Store formula properly. Keep powder tightly sealed and dry; moisture promotes bacterial growth.
Monitor for symptoms after feeding new formula. Early signs include constipation, poor suck, drooping eyelids, or generalized weakness.
WHAT TO DO IF AFFECTED
Steps for parents who used ByHeart powdered formula
Stop using the formula immediately. Keep the container in case regulators need it for testing.
Watch for symptoms: lethargy, weak cry, poor feeding, constipation, decreased movement.
Seek medical care ASAP if symptoms appear—botulism can progress quickly.
Tell your clinician about the ByHeart formula exposure. Diagnosis is largely clinical.
Ask your doctor about BabyBIG. Only the IBTPP can authorize shipment, but physicians must initiate the process.
Report the illness to FDA’s MedWatch or local public health authorities.