Help please!?

Im a teacher/lecturer and I've taught many students in my time. However I currently have a major dilemma. One of my female students is extremely atrractive and i mean extremely. The problem is she seems very flirtatious with me and it makes things rather uncomfortable as I dont know how to deal with the situation. I value my career too much to make anything of it and I am totally against any form of student/teacher relationship. But should I confront the student and make her aware of her actions or inform a senior member of staff? She isnt out right flirting but it is all the time although it is subtle on occions it is still awkward, thankyou.