akaSylvia
So it looks to me like this comes down to, in any other country, the pilot would have been reported by the medical professionals and grounded until his treatment was completed.
I suspect the German medical privacy laws are a result of the happenings before and during WWII and the euthansia program T4 (
https://en.wikipedia.org/wiki/Action_T4) in which doctors were 'implicated and even forced to disclose medical confdences' to the state authorities.
Any change to these laws are going to have to be debated in the German Parliament and any form of international legislation will be invalid as German state law is supreme.