Human immunodeficiency virus type 1 nucleic acids detected before p24 antigenemia in a blood donor

A blood donation from a 46-year-old homosexual man was discarded because of elevated alanine aminotransferase levels. Thirteen days later, the patient presented with symptomatic primary human immunodeficiency virus type 1 (HIV-1) infection. Virologic investigations were performed retrospectively on blood samples (including the donated blood) obtained before the symptoms. The HIV-1 genome was present, either integrated in mononuclear cell DNA or circulating in plasma, 39 days before the appearance of p24 antigen and 65 days before the appearance of HIV-1 or HIV type 2 antibody. It is concluded that p24 antigenemia is present during only a fraction of the seronegative "window" period. This case illustrates the risk of infection associated with blood transfusion in spite of HIV-1 antibody testing and stresses the need to improve nontechnical exclusion procedures as well as non-antibody-based diagnostic tests.