Unlike the flu and cold viruses the roseola virus cannot and does not live on any surfaces such as counters, bedding, sheets, pillows, clothing etc.
So when someone has the roseola virus there's really no need to disinfect those objects although it's still a good idea to disinfect objects, clothing and surfaces just to keep other viruses such as the cold and flu virus away.
However the person who has the roseola virus will be contagious from 2 days before the spots appear and they will remain contagious with the roseola virus until all the blisters they have from the roseola virus have crusted over.
Children and anyone who has the roseola virus are most contagious with the roseola virus for 12 to 24 hours before the roseola rash appears.