Prevalence of allergy, patterns of allergic sensitization and allergy risk factors in rural and urban children.

Background: We aimed to compare the prevalence of allergic diseases and sensitization in children living in urban and rural areas and to identify potential risk/protection factors associated with allergy.

Methods: School children 12-16 years old, from urban community (n = 201) and rural area (n = 203) were recruited. The data obtained by questionnaire were referred to doctors' diagnosis, skin prick tests (SPTs), and serum specific and total IgE assessment.

Results: The prevalence of allergic diseases in urban children was significantly higher as compared with rural children [asthma 16.42%vs 1.97% (P < 0.001) allergic rhinitis 38.81%vs 10.84% (P < 0.001)]. Positive SPTs to at least one allergen was found in 63.7% of urban and 22.7% rural children (P < 0.001). Significantly higher percentage of allergic rural than urban children were monosensitized or sensitized to 2-4 allergens, but almost a fourfold higher percentage of allergic urban children was found to be sensitized to five or more allergens (P < 0.0001). The history of frequent upper respiratory factor (URT) infections, antibiotic therapy, tonsiltectomy/adenoidectomy were positively associated with development of atopy and sensitization.

Conclusion: Our findings confirm that residence of rural area is associated with a significant lower prevalence of allergic sensitization and symptoms in school children. Several risk and protective factors related to environment and style of life could be identified in both environments.