The CDC is now reporting that the number of sick people has more than doubled in an E. coli O157:H7 outbreak associated with romaine lettuce on sandwiches from Wendy’s restaurants.

As of this afternoon, the Centers for Disease Control and Prevention says it has confirmed reports of 84 people infected. About half of them — 38 — have required hospitalization. In Michigan, there are eight people who have developed hemolytic uremic syndrome (HUS) which is a type of kidney failure that often results in kidney transplant, brain injuries, and sometimes death.

There are also infected people in Ohio, Indiana, and Pennsylvania.

“Among 62 people interviewed, 52 reported eating at a Wendy’s restaurant in the week before their illness started,” according to the CDC’s outbreak update. “Of 17 people with detailed information about what they ate at Wendy’s, 15 reported eating romaine lettuce served on burgers and sandwiches.”

Based on the reports of illnesses, Wendys has stopped serving romaine lettuce on sandwiches at restaurants in the affected regions. The company says the romaine used to make its salads is different from that used on its sandwiches.

When contacted by Food Safety News regarding the supplier or distributor of the implicated romaine, Wendy’s did not answer the questions.

There are questions about the true number of sick people because of the time it takes for diagnosis, confirmation testing, and reporting through the local, state, and federal chain of public health organizations.

Earlier this week Michigan officials reported 55 confirmed patients with dozens more with test results pending. One county in Ohio, Wood County, reported 22 patients. Other counties in the state in the state were also reporting illnesses.

“CDC is not advising that people avoid eating at Wendy’s restaurants or that people stop eating romaine lettuce,” according to the agency’s outbreak update. “At this time, there is no evidence to indicate that romaine lettuce sold in grocery stores, served in other restaurants, or in people’s homes is linked to this outbreak. Investigators are working to confirm whether romaine lettuce is the source of this outbreak and whether romaine lettuce served at Wendy’s restaurants was served or sold at other businesses.”

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