Sick and tired: Does sleep have a vital role in the immune system?

It is a common belief that we are more susceptible to infections when deprived of sleep. Consistent with this, there is increasing evidence that sleep deprivation has detrimental effects on the immune response, indicating that sleep should be considered a vital part of the immune system and that there is a reciprocal relationship between sleep and immunity. This relationship is important because, over recent decades, there has been a documented decrease in the mean duration and quality of sleep in the population. The concept that lack of sleep might be compromising immunity in the population has far-reaching public-health implications for both individuals and society.