Enterohemorrhagic E. coli (EHEC) has been found in lettuce imported from Bavaria, Der Spiegel reported on Tuesday.
The new finding initially suggested that sprouts might not in fact have been the definitive source of the outbreak, but then the E. coli strain on the lettuce was determined to be unrelated to the outbreak strain.
The German E. coli outbreak that has now claimed 36 lives seems to be abating, but the source of contamination remains unclear.
The virus was earlier traced to bean sprouts grown on a farm in Germany's Lower Saxony region, some 70 km (40 miles) south of Hamburg.
On Monday, the Federal Institute for Risk Assessment (BfR) said a family in Lower Saxony became infected with E. coli after eating home-grown sprouts from a seeds kit, suggesting that seeds supplied to several sprout companies may have been contaminated.
Several hundred infected Europeans have developed hemolytic uraemic syndrome (HUS), a severe illness that can lead to kidney disease, coma and death.
