Since I was a graduate trained Veterinary Microbiologist/Bacteriologist/Virologist specializing in the Infectious Diseases of Wildlife, I figured I'd mention what to look for when proscessing a swine carcass:
When performing a necropsy on swine visually inspect for obivious sign of condemnation like external pus pockets, tumors, swollen nutz, maggot infestation, bad smells, malnutrition, stress, etc.
When dismembering the carcass examine lungs for petechial hemorrhages indicating pneumonia and/or excessive nematode larval migration of roundworm larvae. Check heart for enlargement or endocarditis. Examine inguinal and mesenteric lymph nodes for enlargement, if any swollen lymph nodes toss the carcass. Examine liver for friability, take a sharp knife and slice liver, it should cut like butter, if it cuts like toast toss it. Same with kidney, slice like butter, should cut smooth not like dragging knife through sandpaper. Intestinal tract should show no signs of inflammation or hemorrhage, if it does toss it.
Majority of wild animals should be in good health as Nature is quite cruel and does not promote sickness, that does NOT mean they cannot harbor and transmit subclinical infections of Tuberculosis, Salmonella, Brucellosis, enteropathogic E.coli or massive amount of roundworms/threadworms, they do, which is why you wear gloves and cook well done.