The Hygiene Hypothesis and Vulnerability to Asthma

The prevalence of asthma in the developed countries has increased rapidly in the past few decades and is increasing in the developing countries. A powerful and intriguing hypothesis to explain the rapid increase is that our environments are too clean. The reasoning is that early childhood exposure to infectious agents is crucial for normal maturation of the immune system with the result that populations globally are increasing vulnerable to the chronic condition of asthma as a result of improved hygience. The talk will focus on the logic and supporting evidence for the hypothesis and implications for control.