Make sure you sterilize any instruments you use to cut and please keep it isolated from the rest. I'm sorry to say that it looks just like a virus that my catt had a few months ago and I had to dispose of it before it infected the rest.(I took the infected plant to my local extension agent for a confirmed diagnosis before I pitched it) After you cut the leaf you can tell if it's bacterial by breaking the leaf (it should be soft and mushy)and smelling it. If it's bacterial it will give off an awful smell. If it's viral it woun't smell at all. Really hope I'm wrong on this.