Tasting uncooked foods made with flour can make you dangerously ill, according to a study published today in The New England Journal of Medicine. The report, which recounts the detective work that led to a recall of more than 10 million pounds of flour in the summer of 2016, confirms that a type of E. coli bacteria previously discovered lurking in wet environments like hamburger meat and leafy vegetables can also thrive in arid hosts.

“We’re not trying to ruin people’s holidays, but we want them to be aware of the risks,” said Samuel J. Crowe, the lead author of the study and an epidemiologist with Centers for Disease Control and Prevention.

Because of concerns over raw eggs, precautions have long existed for licking batter-laced spoons and nibbling homemade cookie dough. But the new results expand both the array of raw goods to be concerned about — even homemade playdough! — and the reasons to be vigilant. More than a quarter of the 56 patients in the 24-state outbreak were hospitalized. One even went into kidney failure. All of the patients, whose ages ranged from 1 to 95, recovered.

“It’s a new view of flour,” said Dr. Marguerite A. Neill of Brown University Medical School, who was not involved in this study.

In addition to refraining from tasting uncooked flour dishes, she advised people to wash their hands in hot, soapy water after handling flour. As for the final product: high, sustained cooking heat will kill pathogens.

Identifying the cases and the cause was a relentless undertaking that involved doctors and clinics, state health workers and investigators from the Food and Drug Administration and the CDC.

The symptoms patients experienced included abdominal pain, mild fever, vomiting and diarrhea, which was often bloody. Stool samples helped isolate the strain and point to a cluster. By February 2016, federal investigators started tracking the culprit.

Some patients were able to retrieve the bags of flour they used; all came from the same facility in Kansas City, Missouri.

No contamination was found at the General Mills facility where products like Gold Medal flour had been milled and packaged, researchers said. Instead, they speculated, the dangerous bacteria most likely spread earlier, as manure-dropping cattle or whitetail deer roamed through wheat fields. That means, said researchers, the bacteria, identified as two strains of Shiga toxin-producing E. coli, could reappear.