Not really, first yard i was on you had to keep them in for 2 weeks but the horses could touch over stable walls, plus people went to touch new horses so it didn't really work.
2nd yard none at all could turn out straight away, however they had individual paddocks but could touch over the fence. I now have my own place and do seperate any new horses i get like the one i got yest she can see my other horses but they cant touch each other and in a weeks time will let them near each other.
Yes - they spend two weeks in a paddock where they can see but can't touch any of the other horses. Is a strict rule following strangles in one horse which shut the yard down for over 2 months one summer. 2 weeks is better than nothing.