Baby Formula From All Lots Might Be Contaminated With Botulism Bacteria, Company Says

‘Based on these results, we cannot rule out the risk that all ByHeart formula across all product lots may have been contaminated,’ ByHeart says.

Stephen Dexter holds a container of ByHeart baby formula, which was recently recalled by the company, in Flagstaff, Ariz., on Nov. 12, 2025. Cheyanne Mumphrey/AP Photo

A company at the center of a multi-state baby formula recall due to a botulism bacterial contamination said Monday that all lots of its formula may be contaminated.

ByHeart said in an update on its website that it conducted testing on 36 samples from three different lots of its baby formula, showing that five samples contained the type of bacteria that can lead to the potentially deadly infection in infants.