I'll humbly recommend something, acknowledging that this is not my area of expertise, but I think there are mechanisms you could justify from a public health standpoint to report if someone has been in a medical facility when outside of the country. That may potentially be an avenue to identify if someone has engaged in any sort of medical tourism, whether it's a transplant or otherwise. That would be my only consideration, but obviously that's a whole separate ball of wax to consider. That's one possibility.
On November 16th, 2022. See this statement in context.