Can paper/plastic currency serve as a medium for pathogens?
TB is an extremely poor example, because as has been mentioned, it usually requires prolonged contact.
But lets go with something with a low required infectious dose, that's friendly to surface contamination, and persists in the environment: Norovirus.
Can norovirus serve as a medium for pathogens? Absolutely. To be blunt, almost anything will serve as a medium for the right pathogen with some level of efficacy. This is a presentation from the New York Federal Reserve on what contaminates money, but given the outlandish things that can be contaminated with infectious material, there's no reason to suspect money isn't among them.
Wash your hands.