You can replant in the same spot. You must make sure you remove ALL of the bulb and roots of your deseased bulb(s). Virus is a plant only issue. Soils do not carry virus.

Something to think about is why and how your plants got deseased in the first place and then try to remedy that. When you add your new compost and soil make sure it has good drainage properties and avoid compost which may contain animal manure unless it is VERY, VERY well composted. Do not over fertilize, which can damage and weaken the bulbs, making them susceptable to deseases.

Thanks so much for the reply. I'm not really sure why the lilies became diseased. Possibly it's because our soil is wet and lilies aren't supposed to grow well with wet soil, but I haven't had that problem in other garden areas that are wetter. Perhaps because Casa Blanca is an oriental rather than an asiatic. I'm pretty sure it isn't over fertilization, but I appreciate the input.