In most cases the danger period is over in about 3 months after the blood transfusion. Blood transfusion is one of the more common clinical treatments, and commonly used blood products include platelets, red blood cells, cold precipitates, plasma, and more. Blood transfusion is also potentially risky, especially in terms of the risk of transmission of hematologic diseases. The incubation period for some diseases can be about 3 months or even longer. It often occurs with HIV antibodies, which are found to be negative in pre-transfusion tests. The window period is usually 3 months later, and if the HIV antibody test remains negative, the transfusion can be proven to be safe. However, if the antibody is found to be positive 3 months after the transfusion, it is likely to be infected. It is recommended to follow the doctor’s instructions for blood transfusion, with observation and transfusion of guaranteed blood products.