Multistate Infant Botulism Outbreak Associated with Powdered Infant Formula

Area of Science:

• Public Health
• Microbiology
• Epidemiology

Background:

• Infant botulism is a rare but serious illness caused by Clostridium botulinum spores.
• Powdered infant formula has been previously identified as a potential source of infant botulism.

Purpose of the Study:

• To identify the source of an outbreak of infant botulism.
• To investigate the association between Clostridium botulinum type A and powdered infant formula.

Main Methods:

• Case finding through the Infant Botulism Treatment and Prevention Program, California Department of Public Health (IBTPP-CDPH).
• Laboratory analysis of powdered infant formula samples.
• Epidemiological investigation to determine exposure history.

Main Results:

• Clostridium botulinum type A was identified in ByHeart powdered infant formula.
• A common exposure to ByHeart powdered infant formula was noted among affected neonates.
• As of December 10, 2025, 51 cases of infant botulism linked to this formula were reported across 19 states.

Conclusions:

• Powdered infant formula can be a vehicle for Clostridium botulinum transmission.
• Prompt identification and public health intervention, including product recall, are crucial in managing outbreaks.
• Continued surveillance and research are necessary to prevent future infant botulism cases associated with infant nutrition products.