This market resolves once we have a definitive answer to this question. (i.e. "I've looked at all notable evidence presented by both sides and have upwards of 98% confidence that a certain conclusion is correct, and it doesn't seem likely that any further relevant evidence will be forthcoming any time soon.")

This will likely not occur until many years after Lyme disease is no longer a subject of active political contention, and motivations for various actors to distort or hide inconvenient evidence have died down.

I will be conferring with the community extensivly before resolving this market, to ensure I haven't missed anything and aren't being overconfident in one direction or another. 

(For comparison, the level of evidence in favor of anthropogenic climate change would be sufficient, despite the existance of a few doubts here and there.)

If we never reach a point where I can safely be that confident either way, it'll remain open indefinitely. (And Manifold lends you your mana back after a few months, so this doesn't negativly impact you.)

"Come from a laboratory" includes both an accidental lab leak and an intentional release. It also counts if Lyme disease was found in the wild, taken to a lab for study, and then escaped from that lab without any modification. It just needs to have actually been "in the lab" in a meaningful way. A lab worker who was out collecting samples and got contaminated in the wild doesn't count, but it does count if they got contaminated later from a sample that was supposed to be safely contained.

In the event of multiple progenitors, this market resolves YES only if the lab leak was plausibly attributable to many of the cases of lyme disease. It won't count if most of the cases came from natural sources and then there was also a lab leak that only infected a few people.