|Du toit, George|
Submitted to: Journal of Allergy Clinical Immunology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 8/26/2008
Publication Date: 11/10/2008
Citation: Du Toit, G., Katz, Y., Sasieni, P., Mesher, D., Maleki, S.J., Fisher, H.R., Fox, A.T., Turcanu, V., Amir, T., Zadik-Mnuhin, G. 2008. Early consumption of peanuts in infancy is associated with a low prevalence of peanut allergy. Journal of Allergy Clinical Immunology. 122(5):984-901. Interpretive Summary: Our data demonstrates a peanut allergy prevalence in U.K. children of 1.5%, and in Israeli children of 0.21% (p<0.0001). In Israel, >90% of infants less than 12 months old regularly consume peanut compared to <10% in the U.K. The lower rate of peanut allergy (PA) in Israel cannot be explained by genetic differences. We investigated the differences in the allergenicity of most popular peanut products consumed by the school children, and infants in the U.K. and Israel, to determine if differences in allergenicity of the products contribute to the variation in the prevalence of peanut allergy between the two countries. Peanut protein levels from the Israeli and U.K. products tested were found to be between 68-100%. The levels of individual allergens, Ara h 1, Ara h 2, and Ara h 3 in each peanut product was found to be comparable. Similarly, IgE binding analysis with pooled serum from nine allergic individuals was nearly identical when the same amount of peanut protein was used for each product; therefore, the levels of peanut protein, individual allergens, and IgE binding capacity of the popular snacks from Israel and the U.K. cannot explain the large discrepancies in the prevalence of peanut allergy among the two countries. Also, these findings suggest that early and frequent ingestion of high dose peanut-protein during infancy may prevent against the development of PA.
Technical Abstract: Despite guidelines recommending avoidance of peanuts during infancy in the U.K. and North America, peanut allergy (PA) continues to rise in these countries. PA is reported to be a rare occurrence in countries where peanuts are introduced early in infancy. To determine the prevalence of PA among Israeli and U.K. Jewish children with a common ancestral background, and evaluate the relationship of peanut-allergy to infant and maternal peanut consumption, we used a clinically-validated questionnaire to determine the prevalence of PA (and other allergic diseases) amongst Jewish school children (5171 UK, 5615 Israel). A second validated questionnaire assessed peanut consumption and weaning in infancy (77 UK, 99 Israel). The prevalence of PA in the U.K. was 1.85 % and in Israel 0.17% (p<0.001). Despite accounting for atopy, the adjusted Risk-Ratio for PA between countries was 9.8 (3.1-30.5) in primary-school children. Peanut is introduced earlier and is eaten more frequently, and in larger quantities, in Israel than in the U.K. The median-monthly-consumption of peanut in Israeli infants aged 8-14 months is 7.1 grams of peanut-protein and 0 grams in the U.K. (p<0.001). The median times peanut is eaten per month was 8 in Israel and 0 in the U.K. (p<0.0001). We demonstrate that Jewish children in the U.K. have a prevalence of PA that is 10 fold higher than Jewish children in Israel. This difference is not accounted for by differences in atopy, social-class, genetic-background, or peanut-allergenicity. Israeli infants consume peanut in high quantities in the first year of life, whereas, U.K. infants avoid peanuts. These findings raise the question whether early introduction of peanut during infancy, rather than avoidance, will prevent the development of PA.