Investigation Update: Infant Botulism Outbreak, November 2025 | Botulism

Epidemiologic data

Since the last update on November 8, 2025, two new cases from two new states have been added to this investigation: Kentucky and North Carolina. Both cases were hospitalized and treated with BabyBIG®.

As of November 10, 2025, this outbreak includes 15 infants with suspected or confirmed infant botulism from 12 states (see map). Laboratory confirmation for some cases is ongoing. For 14 cases with illness onset information available, illnesses started on dates ranging from August 9 to November 10, 2025 (see timeline). All 15 infants were hospitalized and treated with BabyBIG®. No deaths have been reported. For 14 infants with age and sex information available, they range in age from 16 to 157 days and 7 (50%) are female.

State and local public health officials are interviewing caregivers about the foods infants were fed in the month before they got sick. Fifteen infant botulism cases have been identified that were fed ByHeart Whole Nutrition powdered infant formula before getting sick.

According to information shared by IBTPP, since August 1, 2025, through November 10, 2025, 84 infants nationwide have received BabyBIG® treatment. Among them, 36 (43%) had any powdered infant formula exposure. Notably, more than 40% (15) consumed ByHeart Whole Nutrition infant formula. This information shows that ByHeart brand formula is disproportionately represented among sick infants in this outbreak, especially given FDA’s data that ByHeart represents an estimated 1% of all infant formula sales in the United States. Investigations remain ongoing but have not identified any other infant formula brands or shared exposures that pose a risk to infants at this time.

Laboratory and traceback data

Officials in several states have collected leftover infant formula for testing. Preliminary laboratory results reported by the California Department of Public Health suggest the presence of the bacteria that produce botulinum toxin in an open can of ByHeart infant formula (lot 206VABP/251131P2) that was fed to an infant with infant botulism. Additional product testing by states, CDC, and FDA is ongoing with results expected in the coming weeks.

Public health actions

CDC and FDA are concerned that other lots of ByHeart Whole Nutrition infant may be contaminated and are making infants sick with infant botulism. Parents and caregivers have reported feeding infants in this outbreak different lots of ByHeart infant formula that were not included in the company’s initial recall on November 8, 2025. Parents and caregivers are urged to stop using any ByHeart Whole Nutrition infant formula immediately.