COLORADO, USA — The number of E. coli cases linked to McDonald's Quarter Pounders has risen to 75, according to new numbers released Friday by the Centers for Disease Control and Prevention (CDC). The agency announced the outbreak on Tuesday and said then that 49 people had been sickened.

There are now 75 cases and 22 hospitalizations, which is up from 10. Two of those people, one child and one adult, are being treated for hemolytic uremic syndrome (HUS), a serious kidney issue. A Mesa County, Colorado, resident died, but no new deaths have been reported.

The outbreak has also expanded from 10 to 13 states, the CDC said Friday. The new states are Michigan, New Mexico and Washington. Previous cases were reported in Colorado, Nebraska, Wisconsin, Iowa, Kansas, Missouri, Montana, Utah, Wyoming and Oregon.

All of the 42 people who were interviewed said they ate at McDonald's before getting sick and specifically mentioned eating a Quarter Pounder hamburger, according to the CDC. The agency said infections were reported between Sept. 27 and Oct.

11. RELATED: McDonald's says onions from California-based produce company linked to deadly E. coli outbreak The exact source of the outbreak has not been determined, but health investigators have focused on the Quarter Pounder burgers.

They are specifically looking at the beef patties and the slivered onions primarily used in the items and not others. McDonald’s removed the slivered onions and beef patties used for the Quarter Pounder h.