An E coli outbreak linked to ground beef has sickened 177 people and prompted more than 160,000 pounds of ground beef to be recalled in recent days.  

Federal health officials said Friday that over the past three days, 21 more people have been added to the outbreak count. In total, officials have been able to confirm 177 people infected with the outbreak strain of E. coli O103 from 10 different states. 

The CDC said Friday it's still been unable to identify a common supplier, distributor or brand of ground beef that could account for the whole outbreak. 

But two companies, one from Georgia and one from Illinois, have recalled raw ground beef that was sold to restaurants and institutions because the products may be contaminated with the E. coli. 

The USDA and state regulatory officials continue to test products to determine the source of ground beef supplied to grocery stores and restaurants where some of the people who have gotten sick ate. 

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A recall notice from the U.S. Department of Agriculture's Food Safety Inspection Service says K2D Foods is recalling about 56.7 tons of meat. K2D does business as Colorado Premium Foods of Carrollton, Ga. The meat is in 48-pound boxes labeled "ground beef puck" for institutional use. 

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The beef from K2D Foods was shipped to distributors in Port Orange, Fla. and Norcross, Ga. for further distribution to restaurants.

A separate notice says Grant Park Packing of Franklin Park, Ill, is recalling about 26.6 tons of meat. It is in 40-pound boxes labeled 100% Ground Beef Bulk 80% lean/20% fat for institutional use.

The items from Grant Park Packing were shipped to Minnesota for further distribution. They were also sent to Kentucky for institutional use.

According to the CDC, epidemiological information and lab evidence indicates that ground beef is the likely source of this outbreak and the majority of those who have gotten sick reported eating ground beef. While some said they got ground beef from grocery stores, others said they had it at a restaurant.  

The CDC is reminding consumers to handle ground beef safely and cook it thoroughly to avoid food borne illnesses. 

The majority of the cases from this outbreak have been in Kentucky, Tennessee and Georgia. The CDC's Friday update confirmed 11 more illnesses in Tennessee, eight in Georgia and two in Ohio.  

Cases linked to this E. coli outbreak have also been confirmed in Florida, Illinois, Indiana, Minnesota, Mississippi and Virginia.

Number of people infected in the E. coli outbreak by state (CDC data, as of April 26)

Kentucky - 65
Tennessee - 52
Georgia - 41
Ohio - 10
Florida - 3
Virginia - 2
Illinois - 1
Indiana - 1
Minnesota - 1
Mississippi - 1

Ground beef packages at a grocery story Thinkstock
A variety of packages of ground beef at the supermarket
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