DENVER A Colorado resident has died after eating a McDonalds hamburger tainted with E. coli, the first death linked to a fast-moving outbreak that has already affected nearly a dozen other states nationwide, federal health officials said Tuesday.At least 49 people from 10 states have gotten sick after eating a McDonalds Quarter Pounder hamburger, U.S. Centers for Disease Control and Prevention (CDC) officials said in a news release Tuesday. Ten of those required hospitalization, CDC officials said, including a child who developed complications of hemolytic uremic syndrome, or HUS, a condition that can occur when small blood vessels become damaged and inflamed, according to the Mayo Clinic.Most of the cases (26) are being reported in Colorado. The specific ingredient linked to the illness has not yet been identified, but CDC investigators are focused on two ingredients in particular: Fresh, slivered onions, and fresh quarter pound beef patties. McDonalds has since stopped using both of these ingredients in several states and Quarter Pounder hamburgers are unavailable for sale in Colorado, CDC officials wrote in a Food Safety Alert issued Tuesday.In a statement, Cesar Pia, McDonalds North America chief supply chain officer, said the fast food company is taking swift and decisive action following the E. coli outbreak that is suspected to have come from a single supplier that serves three distribution centers.As a result, he said, McDonald is pulling the Quarter Pounder from its menus not only in Colorado, but across locations in Kansas, Utah and Wyoming, as well as portions of Idaho, Iowa, Missouri, Montana, Nebraska, Nevada, New Mexico, and Oklahoma. Colorado death linked to E. coli outbreak in McDonalds Quarter Pounder hamburgers, CDC saysWe take food safety extremely seriously and its the right thing to do, Pia said. In the meantime, all other menu items, including other beef products (including the Cheeseburger, Hamburger, Big Mac, McDouble and the Double Cheeseburger) are unaffected and available.While most E. coli strains are harmless and part of a healthy intestinal tract in people and warm-blooded animals, some strains of the bacteria can cause severe stomach cramps as well as bloody or watery diarrhea, vomiting or a fever, according to the CDC.Symptoms typically start three to four days after ingesting the bacteria and most people typically recover without treatment after five to seven days.If you recently ate a McDonalds Quarter Pounder and are experiencing these symptoms, you are asked to contact your health care provider and local public health agency.