Stability and inactivation of HTLV-III/LAV under clinical and laboratory environments

The stability of human T-cell lymphotropic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV) under environmental conditions encountered in a clinical or laboratory setting and its inactivation by commonly used chemical disinfectants were investigated. Under our experimental conditions utilizing a highly concentrated viral preparation, virus with an initial infectious titer of approximately 7 log10 tissue culture infectious dose (TCID50) per milliliter can be recovered for more than a week from an aqueous environment held at room temperature (23 to 27 degrees C) or at 36 to 37 degrees C. Virus recovery is reduced at a rate of approximately 1 log10TCID50 per 20 minutes when held at 54 to 56 degrees C. Dried and held at room temperature, HTLV-III/LAV retains infectivity for more than three days with a reduction of approximately 1 log10TCID50 per nine hours. Viral infectivity is undetectable and reduced more than 7 log10TCID50 within one minute with 0.5% sodium hypochlorite, 70% alcohol, or 0.5% nonidet-P40, and within ten minutes with 0.08% quaternary ammonium chloride or with a 1:1 mixture of acetone-alcohol. These results help provide a rational basis to prevent the accidental spread of HTLV-III/LAV in the laboratory or clinical setting.