ByHeart formula botulism outbreak is over, but the recall is not: what parents should know now

The short version: the ByHeart-linked infant botulism outbreak is officially over, but the recall is still active. That means parents and caregivers should still not use any ByHeart Whole Nutrition infant formula, including all lot numbers, all can sizes, and single-serve packs.

According to final federal updates posted on February 26, 2026, and a CDC page updated March 5, 2026, the outbreak totaled 48 cases in 17 states: 28 confirmed and 20 probable. All 48 infants were hospitalized, and no deaths were reported.

For families, the key point is simple: outbreak over does not mean recalled formula is safe to use. If your baby used ByHeart recently, symptoms can take weeks to appear, so it is still important to keep watching and know when to get urgent medical care.

What changed in February 2026

The Centers for Disease Control and Prevention now lists the investigation status as closed. The Food and Drug Administration says no new cases were added after December 2025, and three earlier suspected cases were later found to be other illnesses and removed from the final count.

But the product recall did not end. Federal guidance still says families should not use any ByHeart Whole Nutrition infant formula. That includes cans and single-serve packets, not just certain lots.

This distinction matters because some parents may hear that the outbreak is over and assume any remaining product is safe. It is not. CDC and FDA both continue to tell parents and caregivers to stop using recalled ByHeart formula immediately.

What parents should do right now if they have ByHeart at home

Stop using it right away. Do not feed it to your baby.
Do not buy, borrow, or accept leftover cans or packets from friends, family, resale groups, or pantry cleanouts.
Wash bottles, scoops, storage containers, counters, and other surfaces that may have touched the formula with hot soapy water or in a dishwasher.
Keep monitoring your baby if they used the formula recently, because symptoms may not show up right away.
Get medical care first if your baby has symptoms, and then report the illness or adverse event through FDA’s Safety Reporting Portal if your clinician advises it.

If your baby drank ByHeart formula and seems completely well right now, that is reassuring. But it does not rule out later symptoms, since infant botulism can take several weeks to develop after exposure.

What infant botulism is, in plain language

Infant botulism is rare but serious. It happens when spores from Clostridium botulinum get into an infant’s body, grow in the gut, and produce a toxin that affects the nerves. In babies, that can lead to weakness, feeding trouble, swallowing problems, and breathing trouble.

This is not a reason to panic about infant formula in general. FDA says the investigation has not shown a broader infant-formula supply problem, and no unusual illness pattern has been identified in other formula products.

It is also worth keeping perspective: this outbreak was unusual enough that FDA describes it as the first known infant botulism outbreak tied to infant formula since the condition was first recognized decades ago.

Symptoms to watch for and when to seek urgent care

CDC says infant botulism often starts with:

constipation
poor feeding or weak sucking
loss of head control
difficulty swallowing

Parents may also notice less facial expression, unusual weakness, a weaker cry, or a baby who seems increasingly floppy. If the illness worsens, the muscles used for breathing can become weak too.

Seek immediate medical care if your baby has used recalled ByHeart formula and develops poor feeding, weakness, trouble swallowing, or any breathing problem. Do not wait for symptoms to get worse, and do not wait to report it online before getting help.

The American Academy of Pediatrics’ HealthyChildren site also notes that symptoms can start slowly and worsen over time. Early treatment matters.

What investigators have confirmed, and what they still do not know

Here is what federal investigators say is confirmed: epidemiologic and laboratory evidence linked the outbreak to ByHeart Whole Nutrition infant formula. FDA says genetic testing found matching strains in some finished formula samples, ingredient samples, and clinical samples from sick infants.

That is strong evidence that the formula was the outbreak source. But there is still an important unanswered question: FDA has not identified a single root cause or exact point of contamination.

In other words, officials have evidence linking the outbreak to the recalled formula, but they have not said they know the exact moment, location, or one confirmed supplier event that explains how contamination happened. FDA says that root-cause work is still ongoing.

A peer-reviewed 2026 report in NEJM Evidence, indexed in PubMed, helps explain how investigators first recognized the outbreak and connected it to powdered infant formula. But that report used an earlier snapshot of the investigation, with 51 suspected or confirmed cases as of December 10, 2025. It is useful background, not the final case total. For parents reading about this now, the CDC and FDA pages are the right sources for the final numbers.

Does this affect other formulas or the U.S. formula supply?

Right now, federal officials say this does not appear to signal a broader contamination problem across brands. FDA says no other products have shown an unusual illness pattern that would suggest a wider problem.

FDA also says ByHeart represented about 1% of U.S. infant formula sales, and the recall does not create broader formula shortage concerns. That does not mean every family will find a replacement easily, especially if a baby has a special feeding need, but it does mean this is not being treated as a nationwide formula-supply crisis.

Still, if you shop online, use third-party sellers, or rely on stored formula from friends or relatives, be extra careful. Recalled product should not be for sale, but parents should check labels closely and avoid any remaining ByHeart Whole Nutrition product.

What to ask a pediatrician if you need a replacement formula

FDA says liquid ready-to-feed formula is the safest option for higher-risk formula-fed infants because it is sterile. If ready-to-feed is not available, liquid concentrate is another sterile option to discuss. These may be especially important for babies who were born early or who have medical conditions that make infection risk more concerning.

Before switching, ask your pediatrician or another qualified clinician if your baby has:

prematurity
medical complexity
cow’s milk protein allergy or other suspected food allergy
digestive or growth concerns
a prescription or specialty formula need

Questions that can help at a visit or phone call include:

Is ready-to-feed the best short-term option for my baby?
If I need liquid concentrate, how should I prepare it safely?
Does my baby need a special formula because of prematurity, allergy, reflux, or another condition?
What symptoms would mean I should go to urgent care or the emergency department?

Avoid making major feeding changes based only on social media posts or parent forums. Formula choice can be simple for one baby and much more complicated for another.

What this means for readers

The practical message is straightforward:

The outbreak is over.
The recall is not.
Any recalled ByHeart Whole Nutrition infant formula should still be treated as unsafe to use.

If your baby used the formula recently, keep watching for constipation, poor feeding, weakness, swallowing trouble, or breathing problems. If symptoms appear, get urgent medical care.

And if you need to replace a recalled product, talk with your child’s clinician about the safest next step, especially if your baby was premature, has other medical needs, or uses a specialty formula.

Sources

This article is for general informational purposes only and is not medical advice. Research findings can be early, limited, or subject to change as new evidence emerges. For personal guidance, diagnosis, or treatment, consult a licensed clinician. For current outbreak or public health guidance, follow your local health department, the CDC, or another relevant public health authority.