Federal health officials have dramatically widened the scope of a troubling infant botulism outbreak linked to ByHeart baby formula, now including every illness reported since the company began production in March 2022. The U.S. Food and Drug Administration (FDA) announced on December 10, 2025, that at least 51 infants in 19 states are believed to have fallen ill after consuming ByHeart products—an escalation from the previously reported 39 suspected or confirmed cases. The most recent illness surfaced as recently as December 1, 2025, underscoring the ongoing nature of the crisis.
ByHeart, a New York-based manufacturer of organic infant formula founded in 2016, had recalled all its products sold in the United States on November 11, 2025. The company, which accounted for about 1% of the U.S. infant formula market and sold roughly 200,000 cans per month, is now at the center of a federal investigation and mounting parental outrage. According to the FDA, “investigators cannot rule out the possibility that contamination might have affected all ByHeart formula products ever made.” This sweeping statement has sent shockwaves through the community of parents who trusted the brand for its reputation as a “very natural, very gentle, very good for the babies,” as one mother described.
The Centers for Disease Control and Prevention (CDC) broadened its case definition to include “any infant with botulism who was exposed to ByHeart formula at any time since the product's release.” This expanded definition added 12 more cases to the tally, including some that occurred before the original timeline and others between December 2023 and July 2025. All 51 affected infants, ranging in age from just over two weeks to nearly nine months, required hospitalization. Thankfully, no deaths have been reported.
For parents like Andi Galindo of Redondo Beach, California, the news has been devastating. Her 5-week-old daughter, Rowan, was hospitalized with infant botulism in December 2023 after drinking ByHeart formula. “That's a hard one,” Galindo told the Associated Press. “If there is proof that there were issues with their manufacturing and their plant all the way back from the beginning, that is a problem and they really need to be held accountable.”
Another parent, Amy Mazziotti of Burbank, California, echoed the sense of vindication mixed with anguish. Her son Hank was treated for botulism in March, just weeks after starting on ByHeart. “I’ve known in my gut from the beginning that ByHeart was the reason Hank got sick, and to see that these cases are now part of the investigation brings me to tears—a mix of relief, gratitude and hope that the truth is finally being recognized,” Mazziotti said.
In response to the growing crisis, ByHeart issued a statement late Wednesday, assuring the public that it is cooperating with federal officials “to understand the full scope of related cases.” The company added, “The new cases reported by CDC and FDA will help inform ByHeart’s investigation as we continue to seek the root cause of the contamination.”
The FDA has dispatched inspectors to ByHeart’s plants in Allerton, Iowa, and Portland, Oregon—sites where the formula is produced and packaged. However, the agency has yet to release the findings from those inspections. What is known, according to ByHeart’s own disclosures, is that tests by an independent laboratory found contamination in 36 samples from three different lots. “We cannot rule out the risk that all ByHeart formula across all product lots may have been contaminated,” the company wrote on its website in November. Dr. Jennifer Cope, a CDC scientist leading the investigation, explained, “It looks like the contamination appeared to persist across all production runs, different lots, different raw material lots. They couldn't isolate it to specific lots from a certain time period.”
Inspection records reveal a troubling pattern. In 2022, the year ByHeart launched its formula, the company recalled five batches after a sample at a packaging plant tested positive for cronobacter sakazakii, a different but dangerous germ. The following year, the FDA sent a warning letter outlining “areas that still require corrective actions.” Things only worsened when a ByHeart plant in Reading, Pennsylvania, was shut down in 2023, just before FDA inspectors discovered mold, water leaks, and insect infestations.
Infant botulism, while rare—affecting fewer than 200 babies in the U.S. each year—can be gravely serious. It occurs when infants ingest botulism bacteria that release toxins in the gut, attacking the nervous system. Babies under one year old are especially vulnerable, as their gut microbiomes aren’t yet mature enough to fend off the toxin. Symptoms can take up to 30 days to appear and include constipation, poor feeding, loss of head control, drooping eyelids, a flat facial expression, and difficulty swallowing or breathing. Some babies may seem “floppy,” and in severe cases, may struggle to breathe.
The sole treatment for infant botulism is BabyBIG, an intravenous medication made from pooled blood plasma of adults immunized against botulism. Developed by California’s Infant Botulism Treatment and Prevention Program, BabyBIG is the only source worldwide. Dr. Sharon Nachman, a pediatric infectious disease expert at Stony Brook Children's Hospital, explained that the antibodies provided by BabyBIG are likely most effective for about a month, though they may circulate in a child’s system for several months. “The risk to the infant is ongoing and the family should not be using this formula after it was recalled,” Dr. Nachman advised in an email to the Associated Press.
As more families come forward, legal action is mounting. Several families whose babies were treated for botulism after consuming ByHeart formula have filed lawsuits, alleging that the company’s product was defective and that ByHeart was negligent in selling it. These lawsuits seek financial compensation for medical bills, emotional distress, and other damages.
ByHeart’s recall and the federal investigation have left many parents feeling betrayed—and anxious about the safety of the infant formula supply chain. The company’s last public statement about the recall and how to obtain refunds was posted on its website on November 24, 2025, but for many, the damage has already been done. The FDA and CDC continue to investigate, determined to uncover the full extent of the contamination and prevent future tragedies.
As the story unfolds, parents, pediatricians, and regulators alike are left grappling with an unsettling question: how could a product trusted by so many for its purity and safety become the source of such widespread harm? The answers, when they come, will have far-reaching implications for the infant formula industry and the families who depend on it.
