Mine just get some sudocream onto the scabs to help drying them out quicker. Others spray with the purple spray. It's bacterial so there is not much you can do to, but let it run its course. She will be a carrier, so may run through your flock in due course.
I have had it very severely in the lambs last year just after weaning, and they stopped eating... but again not much you can do. I think it may also be stress related, so if your ewe is new to your holding it may have just erupted after travelling/new field etc etc.