Context: Many recent cross-sectional studies have suggested that lack of early exposure to communicable diseases, including measles, in affluent countries may have increased rates of atopic disease.
Objective: To study the association between natural measles infection and atopy.
Design and setting: Cross-sectional nationwide study in Finland using data gathered between November 1, 1982, and June 30, 1986.
Subjects: A total of 547910 individuals aged 14 months to 19 years who at the time of measles-mumps-rubella (MMR) vaccination had relevant information collected on the occurrence of measles and allergic rhinitis, eczema, and asthma.
Main outcome measures: Lifetime occurrence of atopic manifestations in subjects who had had measles compared with those who had not, expressed as age-specific and age-adjusted prevalence ratios.
Results: The age-adjusted prevalence ratio of atopic manifestations among those who had had measles (n = 20 690) compared with those who had not (n = 527 220) was 1.32 (95% confidence interval [CI], 1.27-1.36) for eczema, 1.41 (95% CI, 1.33-1.49) for rhinitis, and 1.67 (95% CI, 1.54-1.79) for asthma. The positive association between measles and atopy was evident at all ages, in both urban and rural dwellers, and among subjects with many or few contacts at home or in day care.
Conclusions: Based on our data, measles and atopy occur more frequently together than expected, which does not support the hypothesis that experiencing natural measles infection offers protection against atopic disease.