The first fatality in the United States associated with the outbreak of E. coli O104:H4 in Europe was an Arizona man who had traveled to Germany, the Centers for Disease Control and Prevention confirmed Friday.

The CDC had been investigating whether the man’s death in June was related to the outbreak. 

In its update on the investigation, the CDC said the sprouts-linked outbreak centered in Europe includes six cases of O104:H4 infection in the U.S. Five of the U.S. patients were exposed to the pathogen in Germany and one had close contact with a patient in Michigan. In addition to Arizona and Michigan, the illnesses were reported in Massachusetts, Wisconsin and North Carolina.

Five of the U.S. patients, including the Arizona man who died, developed the severe kidney-damaging complication, hemolytic uremic syndrome, or HUS. 

European public health authorities have said the likely cause of the outbreak was a single lot of Egyptian fenugreek seeds imported to Europe and used to grow sprouts that were consumed in Germany and France.  The European Union has ordered a recall and temporary ban of fenugreek seeds.

“Given the possible severe health impact of exposure to a small quantity of contaminated material, and in the absence of information regarding the source and means of contamination and possible cross-contamination, all lots of fenugreek seeds from the identified exporter should be considered suspect,” the CDC report stated.

The CDC update reinforced earlier reports, which have said the O104:H4 strain of E. coli, while rare, is not unlike various strains of E. coli in nature.  “E. coli, like many other bacteria, exchange genetic material and there is no evidence to think that this strain has been modified intentionally,” the CDC stated. “Because of minimal person-to-person transmission associated with this strain, there is also no evidence to indicate that it will cause a pandemic or spread around the world.”

On Thursday, the European Centre for Disease Prevention and Control revised its outbreak toll downward, explaining that the EU had adjusted the numbers to include only probable and confirmed cases. Given that, the latest total from the World Health Organization was 3,941 illnesses and 52 deaths in a dozen European countries and North America.