Is there a way to find out if you are currently infected with anything? I know you can see how many diseases you've contracted historically, but it doesn't show whether or not you are cured.

Go to your magic menu and scroll all the way down to active effects. Your diseases if there are any will be in red text -s-

It's listed under "effects" (or active abilities) I think under the magic section. It'll be highlighted in red. If you use a Cure Disease potion or head to a shrine, you'll be cured and the disease no longer listed there.

You will also get hints from NPC's that you have some sort of ailment as they comment that you don't look well or have hair growing out of your ears etc.

I wondered what that was all about, I thought it was because I was using restoration spells. Thank you all for your replies, I'll have a look under the magic section as you suggest.