CDC declares Nara Organics infant botulism outbreak over as genetic testing links it to 2025 ByHeart outbreak

As of August 27, 2026, CDC has declared over the multistate outbreak of infant botulism linked to Nara Organics Whole Milk Organic Powdered Infant Formula, according to an update on FDA's outbreak investigation page.¹ FDA, CDC, the California Department of Public Health (CDPH) Infant Botulism Treatment and Prevention Program (IBTPP), and state and local partners investigated 4 confirmed cases across California, Pennsylvania, and Washington, with illness onset between April and May 2026; no new cases have been added since July 3, 2026.¹

Nara Organics agreed to a full recall of the product on June 13, 2026, a day after FDA first contacted the company. “Nara is taking aggressive action to ensure the safety of the babies and families” involved in the investigation, the company said in a statement.² The outbreak's most consequential finding came later, when whole genome sequencing tied a Nara Organics case directly to the separate 2025 outbreak linked to ByHeart infant formula.¹

Whole genome sequencing links the Nara Organics and ByHeart outbreaks

FDA and state partners collected samples from case patients as well as finished-product and ingredient samples, then performed whole genome sequencing (WGS)—DNA fingerprinting—on Clostridium botulinum, the toxin-producing bacteria responsible for the illnesses.¹ One clinical sample from an infant in the Nara Organics outbreak was a genetic match to a clinical sample from an infant in the 2025 ByHeart outbreak, to a ByHeart powdered infant formula base sample from that investigation, and to 4 samples of unopened ByHeart formula cans.¹

FDA determined that the implicated Nara Organics lots were made with milk supplied by Organic West Milk and spray-dried by Dairy Farmers of America—the same suppliers linked to the November 2025 ByHeart Powdered Infant Formula outbreak.¹ Combined, the matching WGS results and shared supply chain indicate a common source of contamination between the two outbreaks, though the FDA says there is not yet enough evidence to determine whether the milk was contaminated before drying or during the drying process; the agency's root-cause investigation is ongoing.¹

Outbreak and recall recap

The recalled product, manufactured in Europe, was distributed nationally through Target stores, Target.com, and Nara.com between July 2025 and June 2026, representing less than 1% of US infant formula sales.^1,2 All 4 affected infants were hospitalized and treated with botulism immune globulin intravenous (BabyBIG).² An earlier FDA update, issued June 26, 2026, after 3 cases had been confirmed, cited observations of deficiencies at the formula's manufacturing facilities.¹

Clinical guidance for pediatricians

Most infants with infant botulism initially develop constipation, poor feeding, loss of head control, and difficulty swallowing, which can progress to difficulty breathing and respiratory arrest, according to the FDA.¹ Diagnosis is clinical, and BabyBIG treatment should not await laboratory confirmation.² Physicians who suspect infant botulism should contact the IBTPP at 510-231-7600, available 24 hours a day.¹ Parents who used recalled formula have been advised to retain any opened cans labeled “do not use” and to continue monitoring infants for delayed-onset symptoms.¹

FDA response across the infant formula industry

FDA says it continues to work with the companies involved in both outbreaks, and with the infant formula industry more broadly, to prevent future contamination events; further updates will be posted to the agency's post-outbreak response activities webpage.¹ The confirmed supply-chain link between the Nara Organics and ByHeart outbreaks follows a separate global cereulide contamination event, traced to contaminated arachidonic acid oil, that sickened 144 infants across 10 countries in late 2025 and early 2026.⁴ FDA has urged infant formula manufacturers and their supply-chain partners to track recall notices and outbreak investigations and to verify that ingredient-related risks are controlled before products reach store shelves—guidance now underscored by the genetic and supply-chain link connecting two separate outbreaks.⁴

References

1. US Food and Drug Administration. Outbreak investigation of infant botulism: powdered infant formula, June 2026. Updated August 27, 2026. Accessed August 27, 2026. https://www.fda.gov/food/outbreaks-foodborne-illness/outbreak-investigation-infant-botulism-powdered-infant-formula-june-2026

2. FDA and CDC investigating multistate infant botulism outbreak linked to recalled Nara Organics powdered infant formula. Contemporary Pediatrics. Published June 15, 2026. Accessed August 27, 2026. https://www.contemporarypediatrics.com/view/fda-and-cdc-investigating-multistate-infant-botulism-outbreak-linked-to-recalled-nara-organics-powdered-infant-formula

3. US Food and Drug Administration. Outbreak investigation of infant botulism: infant formula, November 2025. Accessed August 27, 2026. https://www.fda.gov/food/outbreaks-foodborne-illness/outbreak-investigation-infant-botulism-infant-formula-november-2025

4. FDA presses infant formula makers to tighten supplier oversight after botulism, cereulide contamination. Contemporary Pediatrics. Published July 13, 2026. Accessed August 27, 2026. https://www.contemporarypediatrics.com/view/fda-presses-infant-formula-makers-tighten-supplier-oversight-botulism-cereulide