Tetanus is not directly related to how deep the wound is. The pathogenic bacteria of tetanus belong to anaerobic bacteria, which can invade the human body by wounds, and the important condition for the formation of its infection is the formation of an anaerobic microenvironment in the local wounds, such as wounds so deep that they need stitches, or a history of more serious trauma, such as nails, wood, thorns, and other sharp objects, such as stabbing and stabbing wounds. The wound is deep and thin, which is a breeding ground for tetanus bacilli, and the small external wound opening, filled with necrotic tissue and blood clots, creates an anaerobic environment suitable for tetanus bacilli to grow and multiply. If anaerobic infection is present at the same time, the latter will consume the oxygen remaining in the wound, making tetanus more likely to occur. Usually, tetanus infection does not occur in superficial wounds, such as simple surface abrasions, after timely debridement, there is no need to take a tetanus shot for prevention. Usually after being scratched even if the wound is not very deep, it is best to go to the hospital immediately, under the guidance of the doctor for treatment.