What to Know About Infant Botulism Outbreak Linked to Baby Formula

The number of cases has risen to 15.

ByHeart infant formula. Courtesy of the FDA

ByHeart infant formula. Courtesy of the FDA

At least 15 babies have been sickened during a recent outbreak of infant botulism.

Nine of the cases have been confirmed as infant botulism type A, with results for the other cases pending, Dr. Erica Pan, health officer for the California Department of Public Health, said on Nov. 10.

The 15 cases across 12 states are up from the 13 cases across 10 states reported over the weekend.

Federal and state officials are investigating the botulism outbreak, which has been tied to formula made by the company ByHeart.

Here’s what to know about the outbreak.

Illnesses Start

The cases of botulism started in August, authorities said.

States reporting cases include Arizona, Illinois, Pennsylvania, and Texas.

Infant botulism occurs when babies eat food or beverages that have spores from a bacterium called Clostridium botulinum.

“Their gut microbiomes are not yet developed to prevent the growth of C. botulinum spores, which can germinate and produce toxin directly in their intestines,” Darin Detwiler, a Northwestern University professor whose expertise is food safety, said in a statement. “This is why health authorities advise against giving honey to infants under one year of age, as honey can contain these spores.”

A treatment for infant botulism called BabyBIG is approved by federal regulators. The treatment is delivered in vials that cost $69,300 apiece, according to Pan.

Formula Recalled

ByHeart, which makes organic formula and is based in New York, on Nov. 8 said it was voluntarily recalling two lots of formula “out of an abundance of caution” and “to remove any potential risk from the market and ensure that the safety and well-being of every baby who uses ByHeart—including our own—will always come first.”

ByHeart said that people who purchased the lots in question should not use the formula and should throw it out. The Centers for Disease Control and Prevention also recommended washing items and surfaces that may have touched the recalled formula, and seeking medical care if your infant consumed the formula and is showing symptoms such as poor feeding and difficulty swallowing.

The voluntary recall applies to two batches of ByHeart infant formula:

• Batch Code: 251261P2, use by: 01 Dec 2026
• Batch Code: 251131P2, use by: 01 Dec 2026

The recalled batches were labeled with universal product code 85004496800.

They could be purchased at retail stores and online. ByHeart has offered to replace the cans at no cost.

Test Detects Bacteria

Testing conducted by the California Department of Public Health detected bacteria that produce botulinum toxin, the agency said the same day as the recall was announced.

The sample was taken from an open can of ByHeart formula that was fed to an infant who fell ill. Officials injected mice with the cultured bacterium and then waited up to four days to see if they got sick.

“These mice got sick really quickly,” Pan said.

ByHeart said that it was treating the test result seriously, but that testing from an opened can “lacks scientific basis to establish causation between the product and illness.”

It added, “Testing unopened cans will provide reliable evidence that will help bring clarity to families who are understandably concerned, as currently, no U.S. or imported formula is required to be tested for Clostridium botulinum.”

Potential Impact on Formula Stock

There is little danger of infant formula shortages because of this outbreak. ByHeart, which was founded in 2016, accounts for an estimated 1 percent of national formula sales, according to the CDC.

A baby formula shortage developed in 2021 after four infants were sickened after consuming formula made by Abbott Nutrition.

Two of the babies died. No direct link was found between the Abbott products and the infections caused by Cronobacter sakazakii, but federal officials closed the company’s Michigan plant after contamination and other problems were detected.

Abbott made about half of the formula in the United States at the time.

The Associated Press contributed to this report.