Baby Botulism Outbreak: FDA Can't Find Cause or Prevention

Key Takeaways

• 48 infants across 17 states were hospitalized from botulism linked to ByHeart formula, with some still recovering months later
• FDA traced contamination through the supply chain but cannot determine where or how bacteria entered
• Three companies involved (ByHeart, Dairy Farmers of America, Organic West) are deflecting responsibility with no public accountability

An Outbreak Without Answers

The Food and Drug Administration this week posted what critics call an "underwhelming" epilogue to a devastating outbreak of botulism in babies. Despite months of investigation and clear tracking of contamination through the supply chain, the agency still cannot explain how Clostridium botulinum bacteria arrived in ByHeart infant formula. Worse, it offers no guidance on how to prevent it from happening again.

"The FDA's investigation into the root cause is ongoing with a focus on ingredients," the agency reported. That single sentence is now the official status of an outbreak that hospitalized 48 infants across 17 states between November 2025 and February 2026.

“The FDA's investigation into the root cause is ongoing with a focus on ingredients.”

— FDA Official Statement, June 2026

Some of these infants are still recovering months after contracting the life-threatening infection. The outbreak was declared over by the FDA and Centers for Disease Control and Prevention on February 26, but answers remain elusive.

The Contamination Trail

The FDA's investigation did produce a detailed trace of the bacteria. Clostridium botulinum produces hardy spores found in soil and sediments. When these spores reach a suitable environment, such as the underdeveloped guts of infants, they grow and produce a neurotoxin that causes flaccid paralysis.

Strains of C. botulinum isolated from sick infants were genetically linked to strains found in ByHeart's formula. Those strains were also linked to powdered whole milk used as an ingredient. The powder was dried from liquid milk at a Nevada facility run by Dairy Farmers of America. The liquid milk came from California-based supplier Organic West, which sold the resulting powder to ByHeart.

The FDA traced contaminated formula and milk powder back to eight whole milk lot powders from 33 fluid milk lots supplied by Organic West. The genetic links are clear. The entry point is not.

"Even though there are several hypotheses, investigational findings could not identify the source or root cause of contamination of the powdered infant formula," the agency concluded.

Three Companies, Zero Accountability

In the absence of FDA conclusions, three companies at the center of the investigation are left pointing fingers. None has publicly taken responsibility for the contamination.

ByHeart released a statement this week saying "FDA has shared that it did not identify any deficiencies in ByHeart's facilities that could explain the root cause of this outbreak." The company appears to be redirecting attention toward its suppliers.

Bill Marler, a lawyer specializing in food poisoning who represents 25 of the sickened infants in litigation, called the FDA's conclusion "a little underwhelming to put it mildly." He told Ars Technica that the agency's epilogue, titled "Post-Outbreak Response Activities," provided a summary "without any real clear guidance for consumers or for the companies going forward."

A Landmark Failure in Infant Formula Safety

This outbreak represents the first documented instance of infant botulism linked to commercial infant formula. That fact alone should have triggered an intense focus on prevention. Instead, the investigation ended with hypotheses but no root cause, leaving the industry without actionable guidance.

The recall itself was successful. Reports indicate 100% of recalled ByHeart products were cleared from retail shelves following the final expansion in November 2025. But clearing shelves does not fix supply chains.

Discussion on Reddit and Hacker News has been heavily critical of the FDA's "underwhelming" report. Community members are demanding stricter testing mandates for raw ingredients like powdered milk. Their frustration centers on a simple question: if the FDA can trace contamination through three companies and multiple lot numbers, why can't it identify where the bacteria entered?

What Happens Next

The FDA says its investigation remains "ongoing with a focus on ingredients." That language suggests the agency suspects contamination occurred at the raw material level, potentially before milk reached the Dairy Farmers of America drying facility. But without proof, the agency cannot mandate changes.

Litigation may provide answers that regulation did not. With 25 families represented by Marler alone, discovery in those cases could reveal internal documents showing what each company knew and when. Civil litigation has historically uncovered food safety failures that regulatory investigations missed.

For now, parents are left with an uncomfortable reality: a contamination event can sicken dozens of infants, trigger a successful recall, prompt a months-long investigation, and still end without explanation or prevention guidance.

Frequently Asked Questions

How many babies were affected by the ByHeart formula botulism outbreak?

48 infants across 17 states were hospitalized. Some are still recovering months after the infection. No deaths were reported despite the severity of cases.

Did the FDA find the cause of the contamination?

No. The FDA traced the bacteria through the supply chain but could not determine where or how Clostridium botulinum entered the formula. The investigation remains "ongoing with a focus on ingredients."

Which companies are involved in the outbreak investigation?

Three companies are at the center: ByHeart (formula manufacturer), Dairy Farmers of America (operated the Nevada facility that dried the milk), and Organic West (California-based supplier of the liquid milk).

What is infant botulism and how does it affect babies?

Infant botulism occurs when Clostridium botulinum spores reach an infant's underdeveloped gut, grow, and produce a neurotoxin. The toxin causes flaccid paralysis and requires hospitalization.

Is ByHeart formula safe to use now?

All recalled ByHeart products were cleared from retail shelves. However, the FDA has not issued guidance on prevention, and the root cause remains unknown.

Source: Ars Technica