What does “RHD blood type positive” mean?

RhD-positive blood type means that the D antigen is present on the surface of the individual’s red blood cells within the Rh blood group system. This is one of the common blood types classified under the Rh system, which—following the ABO blood group system—is another major human blood group system. Among the 49 known antigens in the Rh system, the D antigen is the most clinically significant and immunogenic. Consequently, individuals whose red blood cells express the D antigen are designated as RhD-positive. In China, approximately 99.7% of Han Chinese are RhD-positive; the prevalence is about 90% among certain ethnic minorities and roughly 85% among Caucasians. Individuals with RhD-positive blood typically require no special lifestyle precautions. In contrast, RhD-negative blood is relatively rare and is colloquially referred to in China as “panda blood.”