Well Poindexterity, I hope this isn't dull lol.
I have to report that the syndrome seems mostly contained, although not completely eliminated. I just need to wait for some lingering infected pets to die off that are still clinging to life. For animals I put them in different pens, even among the same species to limit intermingling. I butchered the stray ones and have separated the named ones.
For dwarves, I am struggling to find anymore infected ones though I'm keeping my eye out for it. A strange thing happened with one infected child I followed who was sitting in a hospital bed waiting to be diagnosed. When the pump operator diagnoser came a message came up saying the diagnosis was cancelled since the kid was not at rest and after her symptoms were gone. :\
I've lost maybe a few dozen animals and about 8 or so dwarves so far. Recently a child starved him or herself from melancholy. I was getting message spam that a mother of nine could not get to her child and it turns out she was in jail and nearly starved/dehydrated. I suspect she broke the handle that kept a bridge up with a bunch of goblinite which was preventing dwarves from refilling the food stock pile next to her.
I have residual unhappiness but things seem to be holding together. Maybe I can start focusing on my magma forge project soon.