NEW YORK (CBSNEWS.COM) – Twenty-two of the top 25 U.S. burger chains — including McDonald’s, Burger King, White Castle and Five Guys — received a failing grade in a review assessing their practices and policies on antibiotics use in their beef products. Only two chains were given an “A” rating.

The scores were published Wednesday in a report called “Chain Reaction IV: Burger Edition,” which was produced by the Center for Food Safety, Consumer Reports, Food Animal Concerns Trust, U.S. PIRG Education Fund, Friends of the Earth, and Natural Resources Defense Council.

burge 22 Burger Chains Given F Over Antibiotics   Only 2 Get A Rating

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The report says 22 chains received “F” grades “for lacking any announced policy to source beef raised without the routine use of antibiotics.”

Wendy’s received a “D-” because 15 percent of its beef is sourced from producers that cut the use of tylosin, an antibiotic, by one-fifth, it says.

Only two chains — Shake Shack and BurgerFi — received an “A” rating. “Both companies currently serve only beef raised without antibiotics,” the report says.

The report notes that while Fuddruckers, Steak ‘n Shake and Farmer Boys — which received “F grades” — have no antibiotics policies, they offer a burger option made of beef raised without antibiotics.

Overuse of antibiotics in livestock can cause resistant bacteria to spread, putting humans at risk of developing life-threatening infections. The report says many meat producers give animals antibiotics to encourage quicker growth or stave off disease, calling it a routine practice.

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