There is no saying how long it absolutely takes for the wound to become infected, usually it is 6 to 8 hours after the injury. It can also occur 2 to 3 days after surgery. It also varies depending on the site. For some traumatic wounds infection usually occurs 6 to 8 hours after the wound, because the bacterial reproduction time is 6 to 8 hours, so for suspected infected wounds should be timely use of antibiotics to prevent infection. The time of infection of different incisions is different, and needs to be specifically analyzed according to the specific situation of each person. If the wound with heavy infection in the abdominal cavity is usually 3 to 5 days after the operation, it will produce redness, swelling, heat and pain, or oozing of inflammatory fluid. Surface wounds usually develop redness, swelling, pain, and oozing fluid 2 to 3 days after surgery. If the wound becomes infected, it is necessary to actively seek medical attention and follow the doctor’s instructions for proper treatment.