Originally Posted by notorious
Death from normal sickness is very possible.
If you didn't pick up on it, when he returned and opened his eyes, they were all dark red. They showed Rick noticing one particular zombie at the fence multiple times. The guy with the crazy red bulging eyes. Pretty sure there is a few form of the infection. Looks like it likely did come from the deer Daryl killed too, as they made a point of mentioning him shooting it and showing one dead in the woods, and a boar dying for no reason.