Deep Dive: Shared Milk Supplier Links ByHeart and Nara Organics Infant Botulism Outbreaks — Background, What Changed, Viewpoints, and What to Watch

# Shared Milk Supplier Links ByHeart and Nara Organics Infant Botulism Outbreaks

Parents who have used powdered infant formula from ByHeart or Nara Organics have faced overlapping investigations into infant botulism this year. This week, CDC and FDA updates confirmed that whole-genome sequencing ties a Nara Organics case to the earlier ByHeart outbreak, and both are linked to the same powdered-milk supplier.

## Background

Infant botulism is a rare but serious illness caused by Clostridium botulinum spores that colonize the gut and produce toxin. In infants under 12 months, the immature microbiome can allow spores (harmless to older children and adults) to grow. Powdered infant formula is not sterile; spores can survive manufacturing.

In late 2025, CDC and FDA investigated a multistate outbreak linked to ByHeart Whole Nutrition Infant Formula. Dozens of infants were hospitalized; the outbreak was declared over in early 2026 after a full recall. Testing found the organism in product samples.

In 2026, a separate cluster linked to Nara Organics Whole Milk Organic Powdered Infant Formula led to hospitalizations in multiple states and a product-wide recall. CDC has now declared that outbreak over.

## What changed this week

Whole-genome sequencing showed a clinical sample from a Nara Organics case matched samples from the 2025 ByHeart outbreak, including formula base and unopened cans. FDA identified that both products used milk from the same supplier (Organic West Milk, spray-dried by Dairy Farmers of America). The root-cause investigation into whether contamination occurred before or during drying is ongoing.

FDA has pressed formula makers to strengthen supplier oversight following these events and a related cereulide contamination involving ARA oil.

## Competing viewpoints

- **Supply-chain transparency advocates** argue that manufacturers must know and control farm-level sources, not just accept supplier assurances. Gaps in visibility (ByHeart reportedly had no control over specific dairies chosen by its supplier) are seen as systemic risks.
- **Industry and regulatory caution** notes that spores are environmental, testing has limits, and no evidence yet proves the exact contamination point. Full recalls and outbreak declarations prioritize infant safety while investigation continues.
- **Parents and clinicians** emphasize immediate action: stop using recalled lots, watch for constipation, poor feeding, weak cry, or floppy movements, and call the California Infant Botulism Treatment line (510-231-7600) if suspected. Treatment with BabyBIG should not wait for lab confirmation.

## What to watch next

- FDA root-cause findings on the shared milk supply and any additional lots or brands.
- Whether other powdered formulas using the same supplier or drying process face testing or recalls.
- Updated FDA guidance on supplier verification and environmental monitoring for spore-formers.
- Any new cases or expansions of the investigation.
- Clinical updates on recovery of affected infants and long-term outcomes.

**Practical steps for parents today**
- Check any remaining ByHeart or Nara Organics formula against recall lists on FDA.gov.
- Discard recalled product; do not donate or use.
- Prefer ready-to-feed or liquid concentrate if concerned, or discuss alternatives with your pediatrician.
- Know the signs of infant botulism and have the 24/7 consultation number handy.
- Continue routine well-child care and vaccinations; this is a rare contamination issue, not a reason to avoid all formula.

This is not medical advice. Consult your pediatrician or the Infant Botulism Treatment and Prevention Program for individual concerns.