That's because there is a difference between trichinosis from undercooked pork and E. coli from the unhygenic handling of cut meat in general. E. coli mostly infects just the surface of cut meat so as long as it's cooked well on the outside, the insides can still be quivering and ready for action. Trichinella, on the other hand, can be found throughout pork and thorough cooking is the only way to render it harmless.