Virucidal activity of olanexidine gluconate against SARS-CoV-2

Antiseptics have been used for infection control against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Ethanol (EtOH) was found to be effective against SARS-CoV-2, while chlorhexidine gluconate (CHG) was less effective. Therefore, virucidal activity may differ between different classes of antiseptic agents. In this study, the efficacy of antiseptics against SARS-CoV-2 was evaluated, and effective agents for infection control were identified. The following antiseptics were used in this study: 1.5% olanexidine gluconate (OLG); 80% EtOH; 1% sodium hypochlorite (NaClO); 0.2% benzalkonium chloride (BKC); 1% povidone-iodine (PVP-I); 0.5%, 1% and 1.5% CHG; and 0.5% alkyldiaminoethylglycine hydrochloride (AEG). The virucidal activity was evaluated at 0, 0.5, 1, 2 and 3 min according to EN14476. After 0.5 min of exposure, 1.5% OLG, 80% EtOH, 1% NaClO, 0.2% BKC and 1% PVP-I inactivated SARS-CoV-2 below the detection limit. The virus survived in the presence of 0.5% CHG, 1% CHG or 0.5% AEG for 3 min. The virucidal activity of 1.5% CHG was insufficient after 0.5 min of exposure. The results showed that virucidal activity against SARS-CoV-2 differs depending on the class of antiseptic agents used under clean conditions. Despite belonging to the same class of biguanide antiseptics, OLG was more effective against SARS-CoV-2 than CHG.