Tests wont pick up on some, but carers will feel unwell. At that point the will to self isolate to be on the safe side comes up against material realities like getting their full wage. That will be one of the routes into the homnes for this virus. Others exist...as I said above: hospitals breaking under pressure are discharging care home residents again.
Your generalising though that care workers will just ignore if they feel unwell in turn for wages.
They get tested weekly thats all they can do. If its positive they isolate. If its negative they work. There is no in between, its very clear.
My sister works on her shift with 5 other staff members and at some time or another they have all isolated through getting tested.
Hospitals will discharge anyone well enough to leave the hospital as well mate, that's always been the case. Beds are at a premium so if you can recover at home they'll send you home or sent back to a care home thats what they'll do.
There is no way of keeping a lid on this thing Dave, if we all do our bit it certainly helps but the only 100% exit plan is the vaccine. The sooner everyone has it the better.