Special rules of isolation were placed by the Torah on one who was found to have tzaraas. According to the Sforno and others, specifically, he would be expelled from all the camps including that of B'nai Yisroel, residing outside them all; in the time of the settlement of Eretz Yisroel, he was excluded from any walled city. He had a number of laws individually isolating him as well, involving whom he could live with in his banishment (only with others suffering tzaraas, not with those banished for other reasons); allowing his hair to grow and covering his face and lips; and even verbally warning anyone who approached him.
At Special Olympics games, where everyone is included.
Of course we don't have anything like tzaraas now. Yet we as communities choose to act as if we do by excluding individual people based on non-halachically supported prejudices. We judge that those people perform specific aveiros which we distain (yet we welcome others who we know regularly perform other halachically prohibited actions) and tell them they are not welcome in our synagogues. We insult or exclude those whose disabilities make them more difficult to welcome, even if they are the very ones who most need our inclusion. We ignore the family whose hashgafa seems different from our own or actively discourage their participation in our community activities. We almost seem to look for opportunities to exclude rather than to enrich our own lives and circles by including others.
Special Olympics Track and Field relay team.
The Torah halachos are quite clear. If a Kohen declared tzaraas, there was no second opinion of his view. But barring the declaration by a Kohen that tzaraas was present, it was not. There was no exclusion, no tearing down of homes, no destruction of property, no negative association at all. We must bear in mind that at all times, we must be inclusive, welcoming, encouraging, for those we are excluding belong in the holiest of places and not outside our walls.