During dinner at the Cheeesecake Factory, while Howard is talking a woman in a blue jacket and brown pants walks by behind him twice going in the same direction.
When they're in the waiting room, Sheldon is talking about diseases and says, "...and other assorted coccuses."
The plural of "coccus" is "cocci" (pronounced kaak-see).
Sheldon states that he is waiting for the pathogens to cross his microvilli into his circulatory system. For being a genius scientist, he doesn't understand biology very well (which he scoffs at Amy's work in multiple episodes) since pathogens in the GI tract would have a local effect and cannot cross through the villi into circulation, only small molecules can. Only when the intestines are perforated can septicemia happen.