Infant Botulism Outbreak Testing Handled by Minnesota Public Health Laboratory

The final months of 2025 saw a national outbreak in infant botulism cases. According to the Centers for Disease Control and Prevention (CDC), 51 babies were affected across 19 states. No new cases have been found since December 10, 2025.

The CDC worked with the Food and Drug Administration (FDA) and state public health laboratories to discover the cause: ByHeart Whole Nutrition Infant Formula. All products from the brand have been recalled, and anyone who owns ByHeart Whole Nutrition Infant Formula should throw it away immediately.

From November 2025 through January 2026, the Minnesota Infectious Disease Laboratory, a section of the Minnesota Public Health Laboratory, tested seven samples for infant botulism and confirmed two cases. In a typical year, the lab will test around 12-15 samples for the disease.

Few laboratories nationwide test for clinical infant botulism

The Minnesota Infectious Disease Laboratory is the only facility in the state, and one of only around a dozen state health laboratories, that tests for potential cases of infant botulism. Surrounding states, including Wisconsin and Iowa, send samples to Minnesota for testing. 

Also, few if any private laboratories will conduct infant botulism testing for clinical cases. The Clostridium bacteria causing botulism are federal select agents, meaning that they can pose a severe threat to public health. Handling federal select agents carries significant legal liabilities. The process of testing samples from patients for infant botulism is also very complex and time-consuming.

Testing to confirm diagnoses and discover outbreaks

Because infant botulism is so dangerous, physicians must begin treatment for it as quickly as possible. They will do so before test results are available, after consulting with the Infant Botulism Treatment and Prevention Program and in-state experts. Infected babies who receive antitoxins early are cured at a very high rate, though full recovery can take months. (Read more at the Minnesota Department of Health’s Botulism section.) 

For families of infants with probable botulism cases, the testing that the Minnesota Infectious Disease Laboratory conducts is therefore most helpful as confirmation. The families can rest assured that their babies do not have a congenital disorder or some other incurable condition.

The other vital reasons to test samples for infant botulism are to track outbreaks and uncover their causes. Labs across the United States share findings with each other and with epidemiologists, such as those of the Minnesota Department of Health’s Infectious Disease Epidemiology, Prevention and Control (IDEPC) Division. The epidemiologists gather and analyze information about individual cases to discover sources of disease outbreaks.

For example, in the infant botulism outbreak of late 2025, epidemiologists interviewed families of infected infants and discovered that a large percentage used ByHeart Whole Nutrition Infant Formula. The brand comprised less than 1% of infant formula sold nationwide, according to a Minnesota Department of Health press release. Testing the formula confirmed it was contaminated. Because of this cooperation between laboratories and epidemiologists, ByHeart recalled all lots of the formula and many cases of infant botulism were prevented.

Republished with permission from Bill Marler and Marler Clark. Copyright (c) Marler Clark LLP, PS. All rights reserved.