Four suspected US E.coli cases linked to Germany

ATLANTA - The United States has stepped up surveillance of some imported fresh vegetables and raw salad greens, but there are no signs the US food supply has been tainted by a deadly E.coli bacteria that has sickened thousands in Europe, officials said on Sunday.
The number of suspected US cases involving the E.coli bacteria remained at four on Sunday, all of whom had recently visited Hamburg, Germany, officials said.
"Right now there have been no reports of any additional suspected cases" in the United States, Centers for Disease Control and Prevention spokeswoman Lola Russell told Reuters.