text: The Center for Disease Control (CDC) said 45 people had been infected with a strain of E. coli, 43 of whom reported eating at a Chipotle restaurant.
  The cases were in California, Minnesota, New York and Ohio.
  Earlier this month, the chain temporarily closed 43 outlets in and around Washington and Oregon states.
  This was after health officials investigated an E. coli outbreak that made at least 22 people ill.
  "The epidemiologic evidence available at this time suggests that a common meal item or ingredient served at Chipotle Mexican Grill restaurants in several states is a likely source of this outbreak," the CDC said.
  "The investigation is still ongoing to determine what specific food is linked to illness."
  Chipotle shares are now down by more than a fifth this year, valuing the company at $16.7bn (Â£11bn).
  E. coli is short for Escherichia coli. It is a type of bacterium present in the gut of humans and other animals.
  Most strains are harmless but some can produce toxins that cause illness in humans.
target: Shares in Chipotle have slumped more than 12% after US health authorities reported more cases of E. coli linked to the Mexican restaurant chain.