A food poisoning outbreak tied to McDonald’s Quarter Pounders was caused by a common type of E. coli bacteria that can cause serious illness and death. Particularly vulnerable are young children, older people or those with weakened immune systems.

At least one E. coli-related lawsuit has been filed against McDonald's with more expected to follow.

An E. Coli outbreak that resulted in at least one death has been linked to McDonald’s Quarter Pounder hamburgers, US public health authorities said. The US said there have been 49 cases in this sandwich-related outbreak which spans 10 states.