High Environmental Stability of Hepatitis B Virus and Inactivation Requirements for Chemical Biocides

Than, Thoa Thi; Jo, Eunji; Todt, Daniel; Nguyen, Phuong Hong; Steinmann, Jochen; Steinmann, Eike; Windisch, Marc P

The WHO's proposed guidelines on hand hygiene in healthcare recommend the use of 2 alcohol-based hand rubs (formulation I and formulation II) for surgical and hygiene hand disinfection in healthcare settings and to reduce the transmission of pathogens by hands [10] . Formulation I is based on ethanol, whereas formulation II consists of 2-propanol. To determine the efficacy of WHO formulations I and II against HBV, we incubated viral particles for 30 seconds with both formulations at final concentrations ranging from 0% to 80%. As depicted in Supplementary Figure 1A , viral titers of 10 7 TCID 50 /mL in the control were reduced to undetectable levels at concentrations of >40% for WHO formulation I, whereas at a concentration of 40% WHO formulation II yielded a significant reduction in infectivity (Supplementary Figure 1B) . Finally, we analyzed the susceptibility of HBV to these WHO formulations in comparison to that of other enveloped viruses, which we investigated previously [11] . This comparative analysis of inactivation response curves revealed that HBV has greater stability than hepatitis C virus (HCV), influenza A(H1N1) virus, Middle East respiratory syndrome coronavirus (MERS-CoV), Ebola virus (EBOV), and modified vaccinia virus Ankara (MVA; Supplementary Figure 1C and 1D), which is the chosen test virus for all enveloped viruses in the European Guideline for testing chemical disinfectants and antiseptics in human medicine.