It is in a sense, and I think it is highly related to the workforce mobility highly praised in the US, as people move after better opportunities their network d

It is in a sense, and I think it is highly related to the workforce mobility highly praised in the US, as people move after better opportunities their network degrades, but so does the network of their peers suffer their absence, so in a sense this is contagious. I think this effect is one of the significant cultural factors driving this phenomena, and this does also "contagious" for their family as well, eg. children are very badly effected by this.