If the wound is fresh, there is a risk of contracting AIDS after exposure to the blood of an AIDS patient. However, the risk varies with the size of the wound, the degree of freshness, and the amount of blood from an HIV patient that is exposed. The average probability can be found in the narrative on occupational exposure in the 2018 edition of the Chinese HIV treatment guidelines, where the risk of HIV infection from a wound is about 0.3%, which is not particularly high. However, the probability of infection can be significantly higher if the wound is deeper and the amount of blood of the HIV patient contacted is larger. Therefore, regardless of whether the probability of infection is high or low, the situation needs to be treated and appropriate interruption measures taken.