Chinese Citizen, does she need transit visa to be in Frankfurt Airport?

[WhitG]

I am reaching out for some information regarding one of my friends. She has a valid US visa, but is a Chinese citizen. She will be coming to the United States and leaving in early January to head back to China. The flights that look available leave from New York and go through Germany in Frankfurt Airport then on to Shanghai.

If not spending any time in Germany besides a layover (less than 24 hrs), will she need a transit or tourist visa?

Thank you for your help!