“…MHV strain 1 (MHV-1), MHV-2, MHV-3, MHV-JHM, MHV-A59, and MHV-S are prototype strains. MHV-D, MHV-DVIM, MHV-F-2D, MHV-IN-12, MHV-N, MHV-Nu, MHV-NuA, and MHV-NuU are lowvirulence isolates Hirasawa et al, 1988). MHV-2-CC, MHV-JHM-CC, and MHV-A59-CC are low-virulence mutants of the respective strains 2, JHM, and A59 (Hirano et al, 1984).…”