According to the CDC, in the United States, five confirmed cases and one suspect case of STEC O104:H4 infections have been identified; one death has been reported. Of these six cases, five recently traveled to Germany, where they were likely exposed. The bacterial isolates from the three HUS cases reported in Massachusetts, Michigan and Wisconsin, and two cases with Shiga toxin-positive diarrheal illness reported in Michigan and North Carolina, have been confirmed as matching the outbreak strain. The Michigan case with Shiga toxin-positive diarrheal illness did not travel to Germany, but likely acquired this infection through close contact with the Michigan case with HUS. Arizona has reported one death in a HUS case with recent travel to Germany. This case has not yet been confirmed to have STEC O104:H4 and is currently under investigation.