I Work With A Client That Was Positive For Tb

i work with a client that was positive for tb .........i have had a ppd done prior to working with this client .......my question is since the transmission is airborne and i probably do breathe in air that this client sometimes breathe out ..as i am in close contact providing personal care to this client .......is there a vaccine to prevent the catching of this ........or just the ppd that shows if one has it or has been exposed to it ....point being is there anyway to protect myself from getting it ..and i am worried that breathing in his air may be a possibility of me getting it ........