Researchers also indicated that EO water has antiviral potency on blood borne pathogenic viruses including hep- atitis B virus (HBV), hepatitis C virus (HCV) (Morita et al., 2000; Sakurai et al., 2003; Tagawa et al., 2000) and human immunodeficiency virus (HIV) (Kakimoto et al., 1997; Kitano et al., 2003; Morita et al., 2000). EO water contained only 4.2 mg/L of free chlorine (pH 2.34, ORP 1053 mV) had a greater efficacy against hepatitis B virus surface antigen (HBsAg) and HIV-1 than sodium hypochlorite (Morita et al., 2000). The possible mechanisms underlying the EO water disinfection against blood-borne viruses might include (1) inactivation of surface protein; (2) destruction of virus envelope; (3) inactivation of viral nucleic acids encoding for enzymes; and (4) destruction of viral RNA (Morita et al., 2000). Hanson, Gor, Jeffries, and Collins, 1989 demonstrated that dried HIV is relatively resistant against disinfectants compared with wet HIV. In an insightful work, Kitano et al. (2003) stated that EO water has an inactivation potential against the infectivity of dried HIV-1. They found that the viral reverse transcript (RT) and the viral RNA in HIV-1 are targets of EO water. Sakurai et al. (2003) reported experiments with HBC and HCV-contaminated endoscopes, and concluded that nei- ther HBV nor HCV was detected after the endoscopes were cleaned manually with a brush and disinfected with EO water. Viral DNA was not detected from any endoscope experimentally contaminated with viral-positive mixed sera (Lee et al., 2004; Tagawa et al., 2000). Thus, EO water directly inactivates viruses and its clinical application is rec- ommended. Effectiveness of EO water in preventing viral infection in the food field needs to be further studied.