As an infant botulism survivor, the ByHeart formula outbreak hits home
What parents need to know
When I was just two months old, I suddenly went limp. I stopped eating. I was too weak to even cry. My parents rushed me to the ER where the astute clinicians immediately realized something was very wrong. I was airlifted to a children’s hospital two hours away. The diagnosis? Infant botulism, a rare and life-threatening infection that fewer than 200 babies in the U.S. get annually.
I spent three weeks in the pediatric intensive care unit. I was so dehydrated they had to place an IV in my head.
Today, we’re in the middle of an infant botulism outbreak. Across 12 states, 15 babies have been diagnosed and hospitalized. All 15 were fed ByHeart Whole Nutrition powdered infant formula before getting sick.
An outbreak like this is an all-hands-on-deck situation. For investigations of infant botulism, the California Department of Public Health (CDPH) takes the lead—they operate the nationally recognized Infant Botulism Treatment and Prevention Program. When epidemiologists at CDPH detected the uptick in infant botulism cases and requests for treatment, they rapidly began interviewing parents of the affected babies, in collaboration with the CDC and FDA. They found that in the rise of cases 42% had previously been fed ByHeart infant formula—a trend so strong it was unlikely to have happened by chance. Preliminary results then showed that a can of ByHeart formula fed to one of the cases tested positive. This is key data for linking the ByHeart formula to the outbreak.
Thanks to the tireless dedication of public health scientists at CDPH, we now have an anti-toxin that dramatically improves patient outcomes. CDPH is the only place in the world that manufactures and distributes the FDA-approved antitoxin for infant botulism, called BabyBig. It was invented in 1991, clinically tested between 1992-1997, and received final approval by the FDA in 2003. The antitoxin treatment shortens hospital stays by more than 3 weeks (from 5.7 weeks to 2.6 weeks). (When I had infant botulism, BabyBig wasn’t yet invented.)
The antitoxin treatment is made by combining plasma from adults who have been vaccinated for botulism. But if there’s a vaccine, can we just vaccinate babies? The short answer is no. The vaccine is only for adults with the potential for occupational exposure, whether through laboratory or military work. The existing adult vaccine hasn’t been studied or approved for use in infants. And because infant botulism is so rare, it’s not practical to have massive infant vaccination efforts for it.
To date, use of BabyBIG to treat more than 2,180 U.S. infant botulism patients has resulted in more than 128 years of avoided hospital stays and more than $174 million of avoided hospital costs, according to the CDPH.
Even with an antitoxin, this is still a very scary time for parents, especially for those who rely on formula as their only feeding option.
When I got sick, my mom was shamed by others, as if she had done something wrong to cause my illness. But most infant botulism cases—outside of this outbreak—are caused by swallowing microscopic dust particles found in the environment, not by any decision a parent makes. I was never given honey, the most well-known risk. My infection likely came from random dust or soil, something invisible and totally unavoidable.
That’s what makes this outbreak especially concerning: In all 15 current cases, the likely source appears to be contaminated infant formula from ByHeart—something parents trust to be safe. This underscores the importance of rapid response and rigorous safety monitoring.
If your baby consumed ByHeart formula, be on high alert for these symptoms:
Constipation
Weak cry or poor head control
Difficulty feeding, sucking or swallowing
Diminished facial expression
Muscle weakness or trouble breathing
Seek medical care immediately if any of these symptoms appear and tell your provider if your baby consumed ByHeart formula.
Here’s what you can do right now:
Stop using any ByHeart products. If you fed the recalled product to a baby, close it, label it DO NOT USE, and hold onto it for 30 days. At the end of the 30 days if the baby shows no symptoms, discard it. For product that was never opened or fed, ok to discard.
Offer compassion and empathy. Parents are worried and need support, not blame.
Stay informed. The YLE team will be back with more updates as we have them.
Bottom Line
Behind every infant botulism case is a sick baby and terrified parents. To all the nurses, doctors, epidemiologists, and scientists who cared for me when I was two months old—thank you. You gave my parents hope in one of their scariest moments. And the work didn’t stop. Today, that same dedication to public health is saving more lives. We need these strong health surveillance systems, transparency of science and safety, and compassion for parents trying to navigate this right now.
Love,
Your NY Epi
Dr. Marisa Donnelly, PhD, is an epidemiologist, science communicator, and public health expert. This newsletter exists to translate complex public health data into actionable insights, empowering New Yorkers to make informed and evidence-based health decisions.
Correction (Nov. 13, 2025): This post has been updated to clarify the description of ByHeart’s connection to reported cases and to provide accurate guidance for handling recalled products.