That's true, but we also shouldn't characterize this as a defacto one. Insane quarantine regulations basically prevent teachers from coming to school at all if

That's true, but we also shouldn't characterize this as a defacto one. Insane quarantine regulations basically prevent teachers from coming to school at all if they have even been in contact with anyone who later tested positive, whether or not they are sick, test negative, or have 3 shots. If we saw this same situation sans government regulations then we could conclude it was organically spawned, but that isn't the case here.