Evaluation of an antimicrobial soap formula for virucidal efficacy in vitro against human immunodeficiency virus in a blood-virus mixture.

The virucidal efficacy of a health care personnel hand wash product containing 0.5% parachlorometaxylenol in a sodium C14-16 olefin sulfonate formula was evaluated in in vitro tests with human immunodeficiency virus type 1 (HIV-1) in the presence of 50% whole human blood. The HTLV-IIIRF strain of HIV-1 was suspended in 50% medium-50% whole human blood and exposed to various dilutions of the hand wash product for 30 or 60 s. Following detoxification, residual infectivity was determined by a lytic cytopathogenic assay in MT2 cell cultures. No infectious HIV could be detected after a 30-s exposure to the hand wash product at dilutions of 1:5 and 1:10 and after a 60-s exposure at dilutions of 1:5, 1:10, 1:20, and 1:30. More than 99.9% of the virus was inactivated at these dilutions and exposure times.