Inactivation of human T‐cell lymphotropic virus, type III by heat, chemicals, and irradiation

Abstract
Infectivity of human T-cell lymphotropic virus, Type III (HTLV-III) was inactivated by heat more rapidly if in liquid medium than if lyophilized and more rapidly at 60° than 56°C. When HTLV-III was added to factor VIII suspension, then lyophilized and heated at 60°C for 2 hours or longer there was elimination of 1 × 106 in vitro infectious units (IVIU) of virus. Much of the viral inactivation appeared to result from lyophilization. The application of water-saturated chloroform to the lyophilized material containing virus also resulted in elimination of infectivity. HTLV-III was efficiently inactivated by formalin, beta-propiolactone, ethyl ether, detergent, and ultraviolet light plus psoralen. The results are reassuring regarding the potential safety of various biological products.