Childhood atopy and allergic disease and skin test responses to environmental mycobacteria in rural Crete: a cross-sectional survey.

Background: Through its powerful immunoregulatory effects, infection with atypical mycobacteria may exert a protective effect on the development of childhood allergic disease.

Objective: To examine the relationship between childhood atopy or allergic disease and previous infection with four species of atypical mycobacteria.

Methods: Eight hundred and six children aged 8-18 years and living in rural Crete--most of whom had had previous BCG immunization--underwent skin prick testing with 10 aeroallergens; their parents completed a standardized questionnaire relating to allergic disease.