FDA Presses Formula Makers After Two Botulism Outbreaks
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- The FDA sent a letter to the infant formula industry on July 13, 2026, asking manufacturers to take on more responsibility for the ingredients they buy.
- Two separate multistate infant botulism outbreaks, one linked to ByHeart and one to Nara Organics, were made with milk from the same supplier and dried at the same facility.
- During the first investigation, that milk supplier gave the FDA a customer list that left out the manufacturer later tied to the second outbreak.
- Clostridium botulinum forms spores that survive pasteurization. Cronobacter and Salmonella, the pathogens formula testing was built around, do not.
- The standard indicator test used in dairy processing did not flag the contaminated powder.
Table of Contents
- What the FDA Told the Formula Industry
- Two Outbreaks, One Milk Supplier
- The Testing Gap
- What the Guidance Says for Caregivers
- Closing Thoughts
What the FDA Told the Formula Industry
On July 13, 2026, the FDA sent a letter to infant formula manufacturers and their supply chain partners asking for closer scrutiny of the ingredients they buy.
The letter does not create a new rule and it is not an enforcement action. It sets out what the agency expects: that manufacturers know where an ingredient came from, how it was produced, what risk it carries, and whether that risk is controlled [1].
The agency also said that recall notices, outbreak investigations, and import alerts are safety signals manufacturers should be tracking, and that ignoring them has preceded preventable harm to infants.
Quick Take
- Forty-eight infants became ill across 17 states in the ByHeart outbreak, which the CDC declared over on February 26, 2026 [2].
- An interim count published in NEJM Evidence put the total at 51 suspected or confirmed cases across 19 states as of December 10, 2025, before case review narrowed the final figure [3].
- Of 48 powdered milk samples the FDA collected from four suppliers in February 2026, two tested positive for a Clostridium species carrying a gene associated with botulinum toxin [2].
- Nearly 150 suspected and confirmed cases of cereulide intoxication were reported across 10 countries in a separate contamination event traced to arachidonic acid oil [1].
Two Outbreaks, One Milk Supplier
The first outbreak ran from late 2025 into early 2026 and was linked to ByHeart powdered infant formula. Whole genome sequencing matched two samples from one lot of organic whole milk powder to both a clinical sample and a positive formula sample [2].
The second was announced on June 13, 2026, and linked to Nara Organics Whole Milk Organic Powdered Infant Formula. The lots involved were made with milk supplied by Organic West Milk and spray dried by Dairy Farmers of America, the same two firms in the first outbreak.
The FDA says there is not yet enough evidence to conclude that the shared supplier is the source or route of contamination.
One detail in the agency’s account is harder to read. During the 2025 investigation, the FDA ran a trace-forward to find any other formula manufacturers receiving milk from Organic West Milk. The company provided an incomplete customer list that did not name Nara Organics, and told the agency during the later investigation that the earlier information should have included it [2].
Why Spores Survive Steps That Kill Other Bacteria
Clostridium botulinum spores occur naturally in soil and dust, and reach processing plants and homes on hands, shoes, and surfaces [2].
The spore is a protective structure that survives typical pasteurization and stays viable in dry conditions for long stretches. Cronobacter and Salmonella, the two pathogens formula safety systems were largely designed around, do not form spores and are killed by pasteurization [2].
The illness does not come from bacteria growing in a prepared bottle. Swallowed spores germinate in an infant’s immature digestive tract and produce the toxin there, which is why the same spores are generally harmless to older children and adults [2].
The Testing Gap
Dairy processors have long screened for sulfite-reducing clostridia as a stand-in for the harder-to-detect pathogens in that family.
A study in Frontiers in Microbiology analyzed unopened containers of the recalled formula and the base powder used to make it. C. botulinum turned up in both, and the isolates from one finished lot and a base powder were genetically identical [4].
The finding that matters for the industry is what the samples looked like on the routine screen. The positives came from samples with non-detectable sulfite-reducing clostridia. The authors concluded that indicator-based screening would not have prevented the outbreak even if it had been in place beforehand, and that manufacturers should treat C. botulinum as a hazard reasonably likely to occur in certain ingredients [4].
Spore testing is also slower than routine pathogen work. The FDA notes the process can take two or more weeks and requires specialized capacity that limits how many laboratories can run it [2].
What Federal Sampling Found
In February 2026 the FDA collected 48 samples of powdered milk from four suppliers to formula manufacturers, 12 from each [2].
Forty-six were negative by polymerase chain reaction. The two positives, both organic nonfat milk powder from the same firm, were sequenced and found to contain Clostridium sporogenes carrying a gene strongly associated with botulinum toxin B1.
The agency was careful about what that means. The gene suggests, but does not confirm, that the organism could produce toxin under some conditions, and the powder in question was never used to make infant formula [2].
The sampling did not identify the root cause of either outbreak. It was an initial assessment of how common the organism is in powdered milk, and the FDA has since asked international bodies to look at spore-forming pathogens in formula directly.
Those requests went to the Joint FAO/WHO Expert Meeting on Microbiological Risk Assessment, the Codex Committee on Food Hygiene, and the International Commission on Microbiological Specifications for Foods.
A Separate Toxin Event in Ten Countries
A second contamination event ran in parallel and is often blurred into the first. It involved cereulide, a heat-stable toxin made by some Bacillus cereus strains, and nearly 150 suspected and confirmed cases across 10 countries [1].
The route was different. Contamination was traced to arachidonic acid oil from a single supplier, and no viable bacteria were found in the affected products, meaning the toxin was already present in the ingredient rather than produced by organisms growing in the formula [6].
The European Food Safety Authority reported that most affected infants had mild symptoms, with some hospitalized for dehydration, and that recalls across six EU countries and the United Kingdom reduced the likelihood of further exposure [5]. The ARA oil supplier was added to multiple FDA import alerts [1].
What the Guidance Says for Caregivers
Powdered infant formula is not a sterile product, and the guidance for handling it predates both events.
The WHO and FAO recommend preparing powdered formula with water no cooler than 70 degrees Celsius, then cooling it before feeding, and preparing feeds one at a time rather than in advance [9].
That step targets Cronobacter and Salmonella, which heat kills. It is not a defense against botulinum spores, which survive it. Caregivers cannot address a spore in an ingredient at the kitchen counter, which is the reason the FDA directed its letter at manufacturers and suppliers rather than at parents [1].
Infant botulism presents with poor feeding, a weak cry, drooping eyelids, constipation, and loss of head control [7]. Clinicians treat it with an antitoxin, BIG-IV, that the California Department of Public Health has produced and distributed nationwide since 2003, and the treatment has cut both illness severity and hospital costs [7, 8].
Closing Thoughts
The two outbreaks did not turn on a single sanitation failure inside one plant. They turned on ingredients, on a supplier’s customer records, and on a screening test built for a different class of organism.
That is what the FDA’s July letter is responding to, and it is why the agency has gone to Codex and JEMRA rather than issuing a rule. No agreed standard yet exists for controlling spore-forming pathogens in powdered infant formula.
Parents with a specific concern about a product or a symptom should raise it with their pediatrician, who can check current recall notices against what an infant has actually been fed.
References
1. U.S. Food and Drug Administration. (2026, July 13). *FDA calls on infant formula industry to better safeguard against contaminants introduced through their supply chain.* https://www.fda.gov/food/hfp-constituent-updates/fda-calls-infant-formula-industry-better-safeguard-against-contaminants-introduced-through-their
2. U.S. Food and Drug Administration. (2026). *Post-outbreak response activities: Clostridium botulinum illnesses associated with consumption of powdered infant formula.* https://www.fda.gov/food/outbreaks-foodborne-illness/post-outbreak-response-activities-clostridium-botulinum-illnesses-associated-consumption-powdered
3. Chung, C. H., Barash, J. R., Castonguay, J. L., Penzel-McNamara, C., Lee, K., Read, J. S., Padgett, K. A., Dover, N., Judson, A. J., Lamere, L., Taylor, E. V., Cope, J. R., Conrad, A., Medford, R., Brooks, M., Whitlock, L., Dykes, J., Lúquez, C., Bracken, J. M., . . . Khouri, J. M. (2026). Multistate infant botulism outbreak associated with powdered infant formula. *NEJM Evidence, 5*(4), EVIDpha2600020. https://doi.org/10.1056/EVIDpha2600020
4. Nadala, C., Themeli, E., Forghani, F., Ha, Y., Han, S., Shapovalova, A., Roach, J., Kim, S. H., Thorson, J. L. M., Lee, J. Y., Spear, M., Buhrman, B., Chiu, K., Mullane, N., & Samadpour, M. (2026). Detection and characterization of Clostridium botulinum isolated from powdered infant formula. *Frontiers in Microbiology, 17*, 1800624. https://doi.org/10.3389/fmicb.2026.1800624
5. European Food Safety Authority. (2026). Multi-country foodborne event caused by cereulide in infant formula products 19 February 2026. *EFSA Journal, 24*(3), e9984. https://doi.org/10.2903/j.efsa.2026.9984
6. Haiden, N., Fewtrell, M., Segerstad, E. H. A., Hojsak, I., Norsa, L., & Koletzko, B. (2026). Safety of infant milks: Contamination with cereulide. A commentary by ESPGHAN. *Journal of Pediatric Gastroenterology and Nutrition.* Advance online publication. https://doi.org/10.1002/jpn3.70488
7. Rosow, L. K., & Strober, J. B. (2015). Infant botulism: Review and clinical update. *Pediatric Neurology, 52*(5), 487-492. https://doi.org/10.1016/j.pediatrneurol.2015.01.006
8. Khouri, J. M., Payne, J. R., & Arnon, S. S. (2018). More clinical mimics of infant botulism. *The Journal of Pediatrics, 193*, 218-222. https://doi.org/10.1016/j.jpeds.2017.09.044
9. World Health Organization & Food and Agriculture Organization of the United Nations. (2007). *Safe preparation, storage and handling of powdered infant formula: Guidelines.* https://www.who.int/publications/i/item/9789241595414
