Health officials are investigating at least 13 cases of infant botulism in 10 U.S. states linked to "ByHeart Whole Nutrition" baby formula.

The U.S. Food and Drug Administration and the Centers for Disease Control and Prevention are urging parents to immediately stop using the recalled batches, as the company has initiated a voluntary recall.

The affected infants, aged 16 days to 157 days, have been hospitalized and have received specialized treatment. No fatalities have been reported.