Sims missing their upper bodies

In my game, townies have been missing their entire upper bodies. Its not corrupted cas, its just completely gone. Its like the sim was turned into just legs, and has been rapidly spreading through my saves. It starts as one or two, easy to ignore, but soon enough sims that were normal before lose their torsos, and it becomes impossible to ignore as more and more townies show up on the lot invisible from the waist up.