I am looking for a bed topper (memory foam--ironic, isn't it?--or egg crate) that is also waterproof, OR a waterproof cover for a bed topper. The one on my dad's bed is ruined as a result of his changing status, and I need something that doesn't need to go to the laundry. I need something that can be disinfected with a spray and cloth, so it can be used every day. I want to make Dad's bed more comfortable; he's at a nursing home and his bed is like your typical hospital bed. Thanks in advance for your help!!!