Federal health officials have linked an E. coli outbreak to McDonald’s Quarter Pounders sold in several states.One person from Colorado has died and dozens of others have been sickened in 10 states, the Centers for Disease Control and Prevention said.

Financial services firm Baird has downgraded its rating on McDonald’s to neutral due to increasing concerns over an E. coli outbreak linked to the chain’s Quarter Pounder hamburgers.

McDonald’s says consumers should feel confident ordering from its restaurants despite a deadly E. coli outbreak linked to its Quarter Pounder hamburgers.