Flamestriker
Adult Guinea Pig
. If she is a new piggy, never been with the others and is now in quarantine due to the ringworm then she needs to be well away from the others and you would also need to take steps - new clothes, showers between handling affected and unaffected piggies etc. However, if she was originally in with them then they may well be at risk of developing symptoms in which case quarantining isn’t going to do anything as they have probably already been exposed.
Are your piggies in your amazing piggie house now @Flamestriker?