IFNA1 and infection: To check whether the TBEV strains differed in their potential to interfere with IFN-I cascade, A549 and SK-N-SH cells treated with 100 IU/ml IFNα at 16 h pre- or 1.5, 3 or 6 h post-infection to induce an antiviral state were infected with the different TBEV strains for 26 h at MOI of 1.