As the article states, the immune system actually degrades with age. From the article, "What we know is that as you age your immune system degrades. It's called 'immunosenescence.' You are not able to control infections like you were used to. So the infection goes a little bit crazy at the beginning. You overreact and you get very sick," said Racaniello.

@Amzungu actually I do not believe this.....for example, grandparents seldom get colds from sick grandkids, who brought it forom school or daycare, .but the parents & siblings almost always do.....now resistance to things like cancer May be less, although I have not seen it myself.

@AnneWimsey You don't have to believe it, but that doesn't make it any less of a well researched and well founded fact. It's not a new concept discovered by the authors of this article. It's well established biological knowledge. But, again, I can respect your beliefs and disagree with them at the same time.