Federal health officials on Wednesday expanded an outbreak of infant botulism tied to recalled ByHeart baby formula to include all illnesses reported since the company began production in March 2022.
The U.S. Food and Drug Administration said investigators “cannot rule out the possibility that contamination might have affected all ByHeart formula products” ever made.
The outbreak now includes at least 51 infants in 19 states. The new case definition includes “any infant with botulism who was exposed to ByHeart formula at any time since the product's release,” according to the U.S. Centers for Disease Control and Prevention. The most recent illness was reported on Dec. 1.
No deaths have been reported in the outbreak, which was announced Nov. 8.
Previously, health officials had said the outbreak included 39 suspected or confirmed cases of infant botulism reported in 18 states since August. That's when officials at California's Infant Botulism Treatment and Prevention Program reported a rise in treatment of infants who had consumed ByHeart formula. With the expanded definition, the CDC identified 10 additional cases that occurred from December 2023 through July 2025.
ByHeart, a New York-based manufacturer of organic infant formula founded in 2016, recalled all its products sold in the U.S. on Nov. 11. The company, which accounts for about 1% of the U.S. infant formula market, had been selling about 200,000 cans of the product each month.
News that ByHeart products could have been contaminated for years was distressing to Andi Galindo, whose 5-week-old daughter, Rowan, was hospitalized in December 2023 with infant botulism after drinking the formula. Galindo, 36, of Redondo Beach, California, said she insisted on using ByHeart formula to supplement a low supply of breast milk because it was recommended by a lactation consultant as “very natural, very gentle, very good for the babies."
“That's a hard one,” Galindo said. “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."
Amy Mazziotti, 43, of Burbank, California, said her then-5-month-old son, Hank, fell ill and was treated for botulism in March, weeks after he began drinking ByHeart. Being included in the investigation of the outbreak “feels like a win for all of us,” she said Wednesday.
“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,” she said.
ByHeart officials did not immediately respond to questions about the expanded outbreak.
The FDA sent inspectors last month to ByHeart plants in Allerton, Iowa, and Portland, Oregon, where the formula is produced and packaged. The agency has released no results from those inspections.
The company previously reported that tests by an independent laboratory showed that 36 samples from three different lots contained the type of bacteria that can cause infant botulism.
“We cannot rule out the risk that all ByHeart formula across all product lots may have been contaminated,” the company wrote on its website last month.
Those results and discussions with the FDA led CDC officials to expand the outbreak, according to Dr. Jennifer Cope, a CDC scientist leading the investigation.
“It looks like the contamination appeared to persist across all production runs, different lots, different raw material lots,” Cope said. “They couldn't isolate it to specific lots from a certain time period.”
Inspection documents showed that ByHeart had a history of problems with contamination.
In 2022, the year ByHeart started making formula, the company recalled five batches of infant formula after a sample at a packaging plant tested positive for a different germ, cronobacter sakazakii. In 2023, the FDA sent a warning letter to the company detailing “areas that still require corrective actions.”
A ByHeart plant in Reading, Pennsylvania, was shut down in 2023 just before FDA inspectors found problems with mold, water leaks and insects, documents show.
Infant botulism is a rare disease that affects fewer than 200 babies in the U.S. each year. It’s caused when infants ingest botulism bacteria that produce spores that germinate in the intestines, creating a toxin that affects the nervous system. Babies are vulnerable until about age 1 because their gut microbiomes are not mature enough to fight the toxin.
Baby formula has previously been linked to sporadic cases of illness, but no known outbreaks of infant botulism tied to powdered formula have previously been confirmed, according to research studies.
Symptoms can take up to 30 days to develop and can include constipation, poor feeding, loss of head control, drooping eyelids and a flat facial expression. Babies may feel “floppy” and can have problems swallowing or breathing.
The sole treatment for infant botulism is known as BabyBIG, an IV medication made from the pooled blood plasma of adults immunized against botulism. California’s infant botulism program developed the product and is the sole source worldwide.
The antibodies provided by BabyBIG are likely most effective for about a month, although they may continue circulating in the child's system for several months, said Dr. Sharon Nachman, an expert in pediatric infectious disease at Stony Brook Children's Hospital.
“The risk to the infant is ongoing and the family should not be using this formula after it was recalled,” Nachman said in an email.
Families of several babies treated for botulism after drinking ByHeart formula have sued the company. Lawsuits filed in federal courts allege that the formula they fed their children was defective and ByHeart was negligent in selling it. They seek financial payment for medical bills, emotional distress and other harm.
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.
FILE - Stephen Dexter holds a container of ByHeart baby formula, which was recently recalled by ByHeart, in Flagstaff, Ariz., on Wednesday, Nov. 12, 2025. (AP Photo/Cheyanne Mumphrey, File)
JERUSALEM (AP) — Aid deliveries into Gaza are falling far short of the amount called for under the U.S.-brokered ceasefire, according to an Associated Press analysis of the Israeli military’s figures, as humanitarian groups say the shortfall is severely impacting the strip's 2 million people.
Under the October ceasefire deal between Israel and Hamas, Israel agreed to allow 600 trucks of aid into Gaza a day.
However, Israel’s own figures suggest that an average of only 459 trucks a day have entered the Gaza Strip between Oct. 12, when the flow of the aid restarted, and Sunday, according to an AP analysis. The Coordinator of Government Activities in the Territories, or COGAT — the Israeli defense body responsible for Palestinian affairs — provided the figures.
COGAT said that roughly 18,000 trucks of food aid had entered Gaza from when the ceasefire took effect until Sunday, amounting to 70% of all aid that had entered the territory since the truce.
This means that COGAT estimates that, including the rest of the aid — items that are not food, such as tents and medicines — a total of just over 25,700 trucks have entered Gaza. That is well under the 33,600 trucks that should have gone in by Sunday, under the terms of the ceasefire.
In response to the AP analysis, COGAT insisted on Wednesday that the number of trucks entering Gaza each day was above the 600 mark but refused to elaborate why the figures don't match or provide raw data on truck entry.
COGAT used to give daily figures of trucks entering Gaza during the war but stopped doing so when the ceasefire began. Rights groups say that is because it controls the crossings and has sole access to track how much aid and commercial goods are entering Gaza.
The United Nations and aid groups have often said the amount of aid entering Gaza is far lower than COGAT claims.
The U.N. says only 6,545 trucks have been offloaded at Gaza crossings between the ceasefire and Dec. 7, amounting to about 113 trucks a day. That's according to its online database. The U.N. figures do not include aid trucks sent by organizations not working through the U.N. network.
A Hamas document on Saturday provided to the AP put the total aid trucks that have entered since the truce at 7,333.
This week, the U.N. office for humanitarian affairs, known as OCHA, stressed a “dire” need for more aid for Gaza, saying Israeli restrictions on aid have bottlenecked recovery efforts.
Humanitarian groups say the lack of aid has had harsh effects on many of Gaza's residents, most of whom were forcibly displaced by war. Food remains scarce as the Palestinian territory struggles to bounce back from famine, which hit parts of Gaza during the war.
Starving mothers in Gaza are giving birth to malnourished babies, some of whom have died in hospital, according to a recent report by UNICEF. As winter rains pick up, displaced families living in tents have been left exposed to the elements and without supplies to cope with floods and the biting cold.
“Needs far outpace the humanitarian community’s ability to respond, given persistent impediments,” a UNICEF report said on Monday. “These obstacles include insecurity, customs clearance challenges, delays and denials of cargo at the crossings, and limited routes available for transporting humanitarian supplies within Gaza.”
Israel temporarily stopped all aid entry at least once in response to alleged Hamas violations of the truce. Israel said that Hamas has failed to return the bodies of the hostages in the time period established by the ceasefire, while Hamas has said it struggled to find the bodies due to the destruction left by Israel in the Palestinian territory.
Hamas has also accused Israel of violating the ceasefire terms because of the slow flow of aid, continued closure of the Rafah crossing and ongoing deadly strikes on Gaza.
Since the U.S.-brokered ceasefire began on Oct. 10, the price for a 12-kilogram (26.5 pound) cylinder of cooking gas has shot up to 1,314 shekels ($406), about 18 times what it was before the war.
That has left many residents relying on firewood for both cooking and to stay warm as temperatures plunge ahead of winter, including the 23-member Abed family in the northern city of Jabaliya.
“We are living under the rubble and sleeping on torn sheets. We collect some firewood, and cut sponges to start a fire,” Marwan Abed, 62, told the AP from under the crumbling concrete of his house. He said firewood is the only way “to keep the children warm” and to prepare coffee.
Israel is demanding Palestinian militants return the remains of the final hostage, Ran Gvili, from Gaza. Prime Minister Benjamin Netanyahu's office said Wednesday that Gvili’s return was a condition of moving to the second phase of the ceasefire.
“Once phase one is completed, phase two will begin,” it said.
Hamas militants and Red Cross crews continued to comb the ruins of Gaza City for the final body this week. The militant group Islamic Jihad claimed it had handed over the last hostage’s body in its possession.
On Tuesday, Hamas called for more international pressure on Israel to open key border crossings, cease deadly strikes on the territory and allow more aid into the strip.
Regional leaders have said time is critical for the ceasefire agreement as mediators seek to push the truce into its second, more complicated phase.
Meanwhile, President Donald Trump said Wednesday he would name members to a panel tasked with governing Gaza and overseeing reconstruction under a 2-year, renewable U.N. mandate, “early next year.” Trump had previously said that he would name members to the so-called “Board of Peace,” a key element of the ceasefire deal, by the end of 2025. He did not detail why the timeline for naming board members has shifted.
“It is going to be one of the most legendary boards ever, everybody wants to be on it,” Trump said. He added that kings, prime ministers and presidents have asked to be included on the board.
The director of the Shifa hospital in Gaza, Mohamed Abu Selmiya, said doctors received on Wednesday the body of a 17-year-old Palestinian teenager who had been run over and crushed to death by an Israeli tank in the Jabaliya refugee camp in northern Gaza.
Asked about the incident, Israel’s military said it had killed a militant on Wednesday who had crossed the so-called Yellow Line — which divides the Israeli-held part of Gaza from the rest — in northern Gaza.
It said it could not provide any more details on the incident.
Associated Press writers Megan Janetsky in Jerusalem, Sam Mednick in Tel Aviv, Israel, and Aamer Madhani in Washington contributed to this report.
A thunderstorm is seen over a tent camp for displaced Palestinians in Zawaida, central Gaza Strip, Wednesday, Dec. 10, 2025. (AP Photo/Abdel Kareem Hana)
Displaced Palestinian children walk through a tent camp after stormy weather in Gaza City Wednesday, Dec. 10, 2025. (AP Photo/Jehad Alshrafi)
A young girl looks on as she holds a sandwich at a tent camp for displaced Palestinians on the beach in Gaza City Wednesday, Dec. 10, 2025. (AP Photo/Jehad Alshrafi)
Israeli soldiers gather next to the entrance of a tunnel where the army says the body of soldier Hadar Goldin was held in Rafah, Gaza Strip, Monday, Dec. 8, 2025. Hamas returned his remains to Israel as part of the current ceasefire. (AP Photo/Sam Mednick)
FILE - Hamas militants accompanied by members of the International Committee of the Red Cross (ICRC) head to Zeitoun neighborhood of Gaza City to search for the remains of the final hostage, Dec. 8, 2025. (AP Photo/Jehad Alshrafi, File)
Displaced Palestinians repair their tents at a tent camp on the beach after a stormy weather in Gaza City, Wednesday, Dec. 10, 2025. (AP Photo/Jehad Alshrafi)
