Yah, it's nasty to think about, but I'm not going to get all germophobic and live my life less enjoyable.
I did hear they've cured Aids in people with a new 3 month treatment recently in Germany I believe. Though I'm not going to become promiscous either way. Hepatitis is also treatable if not curable if I'm not mistaken. Medical technology has come a long way with a lot of things.
Not sure how contagious those things are diluted in a river. I'd be more worried of picking up a public phone myself.
*holds her antibacterial close*