ByHeart, a manufacturer of organic baby formula, recalled all of its products sold nationwide Tuesday, days after some batches were recalled in an expanding outbreak of infant botulism.

At least 15 babies in 12 states have been sickened in the outbreak since August, with more cases pending, according to state and federal health officials. All of the infants were hospitalized after consuming ByHeart formula, officials said. No deaths have been reported.

ByHeart officials expanded the voluntary recall from two lots announced Saturday to all products in consumers’ homes and in stores. That includes ByHeart Whole Nutrition Infant Formula and Anywhere Pack pouches of powdered formula. The company sells about 200,000 cans of infant formula a month online and in stores such as Target, Walmart, Albertsons and Whole Foods, according to Dr. Devon Kuehn, chief medical officer.

Company officials said they enacted the unusual recall “in close collaboration” with the U.S. Food and Drug Administration even though no product that was previously unopened tested positive for the contamination. The type of bacteria that produces the toxin is widespread in the environment and could come from sources other than the formula, company officials said.

California health officials earlier confirmed that a sample from an open can of ByHeart baby formula fed to an infant who got sick contained the toxin-producing type of bacteria.

Dr. Steven Abrams, at University of Texas at Austin Dell Medical School, said the first thing parents can do "is immediately stop using that brand of formula called ByHeart that's been recalled."

The U.S. Food and Drug Administration recommended that ByHeart expand its recall because of the number of ill infants that reported consuming the formula, the identification of additional lot codes, the growing case count and the results of the California testing.

Illnesses began between Aug. 9 and Nov. 10, federal officials said. Cases were reported in Arizona, California, Illinois, Kentucky, Minnesota, North Carolina, New Jersey, Oregon, Pennsylvania, Rhode Island, Texas and Washington.

Investigators have not identified any other infant formula brands or other sources of exposure in the outbreak, officials said.

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