A wave of magical disease washes out from a point of your choice within range. Choose up to three creatures in a 30-foot-radius sphere centered on that point. Each target is infected by a magical disease and regains hit points equal to 3d8 + your spellcasting ability modifier.    The next time an infected target takes damage, the disease ends on the target and infects a new friendly creature within 10 feet of the first. The new target regains hit points equal to 2d8 + your spellcasting ability modifier. The next time the new target takes damage, the disease ends on it and moves to another friendly creature within 10 feet of it. The disease continues moving from target to target in this way, reducing the amount of healing by 1d8 each time the disease moves to a new target. The final target regains hit points equal to 1d8 + your spellcasting ability modifier and that instance of the disease ends.    This spell ends early if all instances of the disease end. A creature can be healed multiple times by this spell but can have only one instance of the disease on it at a time. If a creature already has an instance of this disease and would gain another, the previous instance of the disease immediately moves to another valid target as if the creature had taken damage. This spell has no effect on Undead or Constructs.