My Husband Had Surgery On Jan. 3rd To Remove His

My husband had surgery on Jan. 3rd to remove his appendix because cat scan showed the appendix protruding into his colon also during a colonoscopy. He did not have any symptoms or pain. The incision in the belly button became inflamed and just burst open a foul-smelling puss and blood came out, which relieved his pain. What do you recommend as far as whether or not he has an infection and needs antibiotics?