CD8A and Dengue hemorrhagic fever: Furthermore, during febrile phase, patients with DF (7.62%; 3.36–10.92) and DHF (10.35%; 7.99–13.08) have significantly higher percentage of activated CD8+ T cells when compared to OFI (0.76%; 0.15–1.38), and healthy controls (0.32%; 0.026–0.565) (DF vs OFI, p = 0.01, DF vs healthy, p = 0.005, DHF vs OFI, p<0.0001 and DHF vs healthy, p = 0.0001 respectively).