As the number of sick people in the German E. coli O104 sprout outbreak rose to 3,408, including 798 with hemolytic uremic syndrome and 39 dead, scientists have discovered a kitchen employee at a catering company was unwittingly spreading the germ on food.

Hesse state consumer protection officials said that a woman positive for E. coli O104:H4 but had not yet fallen ill – she later developed HUS — passed it to 20 other people via food she handled.