I was re-listening to Purgatory today at work when something crossed my mind...

Angel and Riley were in a pile of human remains for a number of hours while in the arena; I can't remember if it's been confirmed that these were human remains/ zombie remains/ both.

Either way, assuming they were human remains, the possibility that both Angel and Riley contracted STDs at this time are pretty high.

There are spitting sounds made during 10-2 when Angel and Riley exit the pile of bodies. This would indicate that at least one of them had human remains/ blood in their mouths.

The possibility that they could have contracted a deadly disease is very high. I wonder how this could play into future episodes...