CD4 and AIDS: A substantially deviating distribution of patient characteristics, e.g., increased simultaneous infection with the human immunodeficiency virus (HIV) or even inclusion of HIV-related acquired immunodeficiency syndrome (AIDS) patients with CD4+ cell counts of <200 cells per milliliter may have led to much higher sensitivity and specificity of HPV detection in oral rinses obtained from these patients, as, in such patient cohorts, the highest detection rate of HPV in oral samples was reported [40].