E. coli cases linked to McDonald's Quarter Pounders rise to 75 across 13 states: CDC

The number of cases successful a deadly E. coli outbreak linked to McDonald's Quarter Pounders has risen to 75, according to caller national information released Friday.

Cases person been reported successful 13 states, according to nan Centers for Disease Control and Prevention (CDC).

Most of nan cases person been successful Colorado, which has 26 reported cases, and Montana, which has 13 reported cases, according to nan CDC.

Cases person besides been reported successful Iowa, Kansas, Michigan, Missouri, Nebraska, New Mexico, Oregon, Utah, Washington, Wisconsin and Wyoming, according to nan CDC, which further notes that illnesses person occurred betwixt Sept. 27 and Oct. 10 of this year.

A Quarter Pounder hamburger is served astatine a McDonald's edifice connected March 30, 2017 successful Effingham, Illinois.

Scott Olson/Getty Images

Of nan 61 group astir whom nan CDC has information, 22 person been hospitalized, and 2 developed hemolytic uremic syndrome, a serious, perchance fatal complication of E. coli infection that tin origin kidney failure, according to nan CDC.

One decease has been reported successful Colorado successful relationship pinch nan outbreak. The personification was a resident of Mesa County successful nan occidental portion of nan state, according to nan Mesa County section of health.

"The existent number of sick group successful this outbreak is apt overmuch higher than nan number reported, and nan outbreak whitethorn not beryllium constricted to nan states pinch known illnesses," nan CDC said successful its update. "This is because galore group retrieve without aesculapian attraction and are not tested for E. coli. In addition, caller illnesses whitethorn not yet beryllium reported arsenic it usually takes 3 to 4 weeks to find if a sick personification is portion of an outbreak."

McDonald's says either fresh, slivered onions aliases beef patties utilized for nan Quarter Pounder whitethorn beryllium down nan outbreak.

Following nan first announcement of nan outbreak connected Tuesday, nan fast-food institution announced it had proactively removed 2 ingredients from stores crossed 2 affected regions. The company's activity squad said that a mostly of different paper items are not impacted, according to nan CDC investigation.

McDonald's confirmed successful a connection to ABC News that Taylor Farms is nan supplier of nan sliced onions nan fast-food concatenation removed, but it is unclear whether Taylor Farms provides its products straight to McDonald's aliases done an intermediary.

Taylor Farms issued a voluntary callback connected Wednesday for its earthy onions.

The U.S. Food and Drug Administration has said that earthy slivered onions and nan beef patties are nan attraction of their investigation arsenic imaginable E. coli sources, but besides indicated that preliminary information suggests nan onions are "a apt root of contamination."

ABC News' Kelly McCarthy and Taylor Dunn contributed to this report.