Genital herpes testing, blood tests generally reflect antibodies, which have a certain window period. If genital herpes has just occurred, and blisters have just formed, it is very possible that the antibodies are still negative, but the disease has already manifested. Or, the genital herpes may have healed, but the antibodies are positive. Therefore, blood tests can generally only diagnose past infections and are not very accurate for current infections. Thus, the best method for testing genital herpes is to collect blister fluid for DNA testing using PCR methods when blisters are present. This approach is the most accurate, while blood tests can only serve as a reference.