Do we need a new word for "disease?"?

A “disease” can refer to Ebola, or cancer. A cold can even be considered a “disease,” as can poison ivy. I think there should be different terms for something you can catch from someone else, like a cold, and something that is specific to your own body, like cancer, or diabetes.

For the last two weeks my daughter has been suffering from severe headaches. She can’t stand light or sounds. She’s been off work, per doctor’s orders, this whole time. We’ve been kind of worried that she was dying!
Anyway, the headaches and pain is what I imagine a migraine would be like, but neither I, nor my kids, ever have headaches.
So, several Dr’s visits and and an MRI and $1,500 later, they called today with the results. The nurse said she has a sinus disease that is causing her sinuses to swell (she just can’t feel it,) and antibiotics will take care of the swelling.

This has left me very confused.
To me, antibiotics=bacteria, and infection, which can be eliminated.
Disease=possibly permanent.

So what is your take on this, and do we need a new word?