On my last day in the country my ex sneezed a bunch of mucus on me while we were kissing. Luckily I closed my mouth fast enough so nothing went in.
Have you thought about doing anything about what happened?
I've thought of doing nothing about it and I let it go.
Though sneezing can be difficult to control, it was inappropriate of your ex to have sneezed on you and spread mucus on your face. People should always cover their mouths when they sneeze. It was good for you to have forgiven your ex and not hold what happened against them -- if it was an accident.
I was going to make a joke about strep throat.
It's important to clarify what happened. Before joking about it, you should make sure he wasn't being negligent. And if it wasn't an accident, you need to let him know how his behavior made you feel.