If you do catch one (my relatives make drop-gate traps with chain link fencing and heavy iron at the bottoms to prevent rooting under, but by whatever means...) then while feeding it clean, also put some wormer in their water trough 2 or 3 times--they'll drink it all no problems.
If you are wiping out as many as possible, say with a 12 man drive through a section of land, take the plug out of your shotgun and declare war. But you won't be able to escape the whang taste of any boars that way...Steve