The man, whose name was not reported, has denied the allegations against him, World Radio Switzerland reported Thursday.
Officials said the man infected most of his victims with the human immunodeficiency virus while he attended music school between 2001 and 2005.
The victims told police that the man would ask to bite or prick them with an unknown object, which, World Radio Switzerland said, turned out to be a syringe filled with infected blood that the suspect purchased.
The man is charged with causing grievous bodily harm and spread of multiple human diseases.
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