Health officials are investigating an outbreak of E coli food poisoning among students at the University of Arkansas, with dozens reporting symptoms and five people needing treatment in the hospital.

Among those affected are two 19-year-old sorority members who developed serious complications that can lead to kidney failure after being infected with the E coli strain O157:H7. That is according to Bill Marler, a Seattle food safety lawyer who said he reviewed the patients’ medical records after being contacted by the families.

One of the students, Camille Honey of Fayetteville, Arkansas, was hospitalized and on dialysis on Tuesday after both kidneys failed, said her mother, Kris Honey.

“She’s been in 10 out of 10 pain for a week,” Kris Honey said. “She’s been here for 11 days in serious pain and misery.”

Camille, a sophomore, had moved into a sorority house on campus on 4 August and fell ill on 16 August. Her condition worsened and her mother took her to an emergency room. Because Kris Honey had recently watched the Netflix documentary Poisoned, which features Marler and focuses on food-borne illness, she asked ER staff to take a stool sample.

“I would have never asked for that and they never would have done it,” she said. The sample turned up positive for the dangerous strain of E coli.

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About 100 students reported symptoms of E coli infection, officials with the Arkansas department of health said, though it is not clear how many are part of the outbreak. The state confirmed that five people needed to be hospitalized, and officials are analyzing responses from a survey of more than 3,200 people to try to identify the source of the illnesses.

The outbreak, which probably began before 18 August, does not appear connected to the university’s public dining facilities, health officials said in a statement on Monday.

Classes at the University of Arkansas started on 21 August. Sorority members who moved in before school started used food catered by various providers because school services were not yet open, Kris Honey said. She also said she reached out to a group of about 120 mothers of students to warn them about the outbreak.

E coli bacteria live in the guts of humans and animals. Some strains, including E coli O157:H7, produce dangerous toxins that can lead to serious illness and even death in humans. Common sources of E coli outbreaks include ground beef and leafy greens.

Symptoms of E coli food poisoning include a fever higher than 102F (38.9C), diarrhea for more than three days, severe vomiting, dehydration and dizziness.