The frequency of activated cells within the CD161+ MAIT cell subset was significantly elevated in patients with untreated HIV infection and high viral load and slightly in patients receiving ART (median HC = 0.15%, IQR = 0.06–0.28% vs. median high VL = 3.31%, IQR = 0.94–10.35% and median ART = 0.83%, IQR = 0.33–3.63%, Kruskal-Wallis test followed by Dunn's multiple comparisons test: p<0.0001 and p<0.05, respectively). This evidence concerns the gene KLRB1 and HIV infectious disease.