Close. She already knew - it was probably a factor in their breakup. When Scott found out about it, he accused Amanda of giving it to him. She was tested and is clean. I also understand that he is on anti-depressants as a result of the situation.
Robert told the girls that they were in the pool with him. That got them wondering if it can be transferred via the pool or toliet. That sent Allison into hysterics and she started crying, then she started puking.
Big Brother called somebody into the DR to assure everybody that it was not contagious via the toliet.
Big Brother pulled Arnold Shapiro out of bed and they finally got Scott into the DR and then gave him the boot.