Strategies for atopy prevention.

Allergic diseases, particularly in childhood, have become one of the epidemics of the 21st century. Whereas previous strategies for allergy prevention focused on the avoidance of risk factors, more recent approaches are addressing attempts to provide protective factors to infants and young children to achieve immune modulation and tolerance to harmless nutritional or environmental allergens. This change of paradigm for allergy prevention might lead to more effective interventions, which hopefully contribute to reversing the epidemiologic trend of the last decades. In many industrialized countries, the increased prevalence of atopy and asthma has become a serious public health issue. If preventive intervention could be effective at all, it would have to be applied early in life, most probably in early infancy. Unfortunately, our understanding of the natural history of the process of atopic sensitization, atopic dermatitis, and allergic airway disease is still very limited. On the other hand, the evaluation of risk factors and determinants is a necessary prerequisite for any effective intervention.