Regional health ministries and a top health research institute said youngsters from five of Germany's 16 states had been affected by the acute gastroenteritis, with the first cases registered on Tuesday. So far, those affected had not suffered any complications.

"All the institutions which have registered cases of the illness so far are probably being provided by the same caterer," wrote the Robert Koch Institute, which researches and advises the German health ministry on infectious diseases. "This suggests that it is an outbreak caused by food."

The German government and affected states have established a task force charged with looking for the reason for the illness in order to prevent it spreading any further.

(Reporting By Thorsten Severin, Writing by Sarah Marsh; Editing by Myra MacDonald)

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