Nov. 22, 2025, 5:00 AM ESTBy Aria BendixAt least four families have sued infant formula maker ByHeart saying their babies contracted botulism from contaminated formula, as the company faces ongoing scrutiny from federal investigators and a separate class action lawsuit filed last week.In the lawsuits, affected families described harrowing days or weeks in the hospital with their babies, who were placed on IVs and feeding tubes. Many said they had chosen ByHeart’s formula because it contained organic whole milk and minimal additives, making it seem like the healthiest option.The company said in a statement Wednesday that laboratory tests had identified Clostridium botulinum spores in samples of its formula. ByHeart told NBC News that it could not comment on pending litigation and that “the company is focused on the recall and root cause investigation at this time.”According to the Food and Drug Administration, 31 infants who consumed the formula have suspected or confirmed botulism. The cases span 15 states, and all have required hospitalization. No deaths have been reported.ByHeart recalls infant formula sold nationwide due to serious health risks02:03The bacteria that causes botulism can grow in foods that aren’t properly canned or preserved, and it produces a toxin that attacks the nerves. The resulting illness can cause difficulty breathing, muscle paralysis or death.ByHeart said on its website that it has not identified the root cause of the contamination but has shared its test results with the FDA.“We immediately notified the FDA of those findings, and we are working to investigate the facts, conduct ongoing testing to identify the source, and ensure this does not happen to families again,” it said.In an interview with NBC News, Hanna Everett said she started giving ByHeart formula to her daughter, Piper, at around 2 months old. By early this month, Piper was constipated and drooling excessively, and her left eye seemed droopy, Everett said. A friend sent her a link to the ByHeart recall.“Sure enough, the can she had just finished that day was the exact lot number that was affected,” said Everett, who lives in Richmond, Kentucky.Piper was admitted to a children’s hospital on Nov. 9, where she was diagnosed with botulism. Everett said the sight of doctors and nurses struggling to administer IVs and a feeding tube made her throw up.Hanna Everett’s daughter, Piper, in the hospital.Courtesy Hanna EverettTwo friends had to physically prop her up, she said, “because I was just bawling.”“They’re holding your child down that’s not even 4 months old technically at the time, and she’s just screaming bloody murder. And there’s nothing you can do,” Everett said.Piper was given a botulism antitoxin via an IV drip. The treatment isn’t readily stocked at hospitals, so it had to be flown in. Everett said Piper’s condition has improved; she was released from the hospital roughly a week ago.Hanna Everett with her daughter, Piper.Courtesy Hanna EverettBut Everett is still wracked with guilt.“It feels like I let her down when I know that’s not the case. It’s hard to tell yourself that as a mother, because you’re going to blame yourself,” she said.Everett and her husband, Michael, sued ByHeart last week, seeking damages for medical expenses, pain and suffering.“It makes me more angry and just sick to my stomach that it took them as long as it did to own up to this,” she said. “It’s almost like too little, too late.”Everett said she messaged ByHeart about the recall while Piper was in the hospital, and it offered to send her more formula cans.Darin Detwiler, a professor of food regulatory policy at Northeastern University, agreed that ByHeart should have taken comprehensive action more quickly.“They should have identified this on their own, and they should have been forthcoming immediately,” he said.After the FDA alerted ByHeart to the potential link between its formula and the botulism outbreak, the company initially recalled just two lots. The following day, ByHeart posted on its website that there was not enough evidence to link its product to the illnesses because a sample that had tested positive for botulism bacteria came from an opened can, which “can be contaminated in multiple ways.”In court filings, parents suing ByHeart have described states of terror.In the latest suit, filed on Wednesday, a Washington state couple said their daughter had chronic constipation, difficulty feeding and extreme fatigue while taking the formula. She was admitted to the emergency room at 2 months old, the filing says.The family left the hospital on Wednesday, according to the suit. The mother, Madison Wescott, said she doesn’t produce enough milk to satisfy her daughter’s needs without formula.“Knowing that I can’t fully feed my child, and I can’t trust formula companies has really taken a toll on our family,” Wescott said in the suit.In California, Anthony Barbera and Thalia Flores exclusively fed their son ByHeart formula after he was born, according to their lawsuit. By the time their son received the antitoxin for botulism at the hospital, he was no longer eating, connected to multiple IV lines and too weak to cry, their lawsuit says.Arizona parents Stephen and Yurany Dexter said in their lawsuit that their daughter stopped eating altogether in August, refusing the bottle of formula as soon as it touched her lips. She was transported by air ambulance to a children’s hospital. The couple said they feared she might die or never recover fully.Bill Marler, a lawyer representing the Dexters, Wescotts and Barbera and Flores, said ByHeart has “a lot to answer for.”“If there’s a product that should be safe, it should be infant formula,” he said.Before this, no botulism outbreaks had ever been linked to infant formula in the U.S. Formula makers aren’t required to regularly test for Clostridium botulinum, but they must follow sanitary control practices to prevent contamination and are subject to FDA inspections.Most of the major formula recalls in recent years — including the 2022 Abbott Nutrition recall, which contributed to a national formula shortage — were because of potential contamination with a different bacteria, Cronobacter sakazakii. ByHeart also recalled batches of its formula in December 2022 because of possible Cronobacter contamination.In 2023, the FDA sent a warning letter to ByHeart describing “significant violations” at its manufacturing facility in Pennsylvania. The FDA said that ByHeart attributed a batch of formula that tested positive for Cronobacter to a laboratory error, though the lab denied that that was the case. The agency also said there were two water leaks at the facility, and that ByHeart did not evaluate a potential link between the leaks and formula that later tested positive for Cronobacter.ByHeart’s website states that it “undertook action to address the issues and there are no open issues from that warning letter.” The Pennsylvania facility was not involved in the production of formula in the current recall, the company said.Abigail Snyder, an associate professor of microbial food safety at Cornell University, said an FDA warning letter like the one ByHeart got is “pretty unusual,” though there was increased regulatory activity around infant formula after the Abbott recall.“Fewer ingredients and whole milk is a different attribute than microbial safety, unfortunately,” she said.Aria BendixAria Bendix is the breaking health reporter for NBC News Digital.Kenzi Abou-Sabe contributed.