49 hours stay in Shanghai - business purpose

I am confused by diverging information from the embassy, internet pages and also my travel agency.
Do I or do I not need a visa??? I hope someone here can help me.

HERE ARE THE FACTS:
I am a danish citizen
I live in Germany
I fly from Denmark to Shanghai (Pudong) on a business trip
After 49 hours in Shanghai, I then fly out of Pudong to the USA

???

Thanks a lot! :-)