Modified Vaccinia Virus Ankara as a Potential Biosafety Level 2 Surrogate for African Swine Fever Virus in Disinfectant Efficacy Tests

In South Korea, despite the increase in emerging viral pathogens in the veterinary industry, only efficacy-tested, virus-specific disinfectants are allowed to be used. Moreover, domestic testing of disinfectants for their virucidal efficacies against foreign, malignant, infectious pathogens that are unreported within the country and/or contagious livestock diseases that require special attention regarding public hygiene are legally restricted. Therefore, the Animal and Plant Quarantine Agency (APQA) designed a study to select a potential biosafety level 2 surrogate of African swine fever virus (ASFV) for efficacy testing to improve the disinfectant approval procedures. For this, the modified vaccinia virus Ankara (MVA) was compared to ASFV in terms of its susceptibility to disinfectants. Effective concentrations of active substances of disinfectants (potassium peroxymonosulfate, sodium dichloroisocyanurate, malic acid, citric acid, glutaraldehyde, and benzalkonium chloride) against ASFV and MVA were compared; similarly, efficacies of APQA-listed commercial disinfectants were examined. Tests were performed according to APQA guidelines, and infectivities of ASFV and MVA were confirmed by hemadsorption and cytopathic effect, respectively. The results reveal that the disinfectants are effective against MVA at similar or higher concentrations than those against ASFV, validating the use of MVA as a potential biosafety level 2 surrogate for ASFV in efficacy testing of veterinary disinfectants.