INACTIVATION OF HUMAN-IMMUNODEFICIENCY-VIRUS BY A MEDICAL WASTE-DISPOSAL PROCESS USING CHLORINE DIOXIDE

OBJECTIVE: To study the ability of a medical waste disposal process us ing chlorine dioxide to inactivate human immunodeficiency virus type 1 (HIV-1). DESIGN: Stock HIV-1 (HTLV-IIIB strain) was treated with chlo rine dioxide under the following settings: cell culture medium alone, culture medium with 25% blood, culture medium with medical supplies tr eated by the Condor machine (Winfield Environmental Corp., Escondido, CA). MT-2 cells in 96-well tissue culture plates were inoculated with serial tenfold dilutions of treated and untreated HIV-1. Cytopathic ef fect was read on day five, and the TCID50 (50% tissue culture infectio us dose) was calculated. RESULTS: Treatment of HIV-1 with chlorine dio xide in culture medium alone resulted in a 5.25 log10 reduction in TCI D50. Treatment of HIV-1 with chlorine dioxide in the presence of 25% b lood caused a 6.25 log10 reduction in HIV-1 infectivity. Treatment of HIV-1 with chlorine dioxide in the presence of medical supplies treate d in the Condor machine resulted in a 4.75 log10 reduction in HIV infe ctivity. CONCLUSIONS: Chlorine dioxide inactivated HIV-1 in vitro. Chl orine dioxide inactivated HIV-1 in the presence of blood and in the pr esence of medical supplies under conditions that simulated the conditi ons existing in the Condor machine.