Combine first 4 ingredients in a large Dutch oven; bring to a boil. Cook, uncovered, 16 minutes. Add corn and sausage; cook 5 minutes. Add shrimp; cook 3 minutes. Using a slotted spoon, remove vegetables, sausage, and shrimp to a serving platter; discard cooking liquid. Sprinkle vegetables, sausage, and shrimp with salt, pepper, and parsley; toss well.