Epidemiological Investigation and Cohort Study on Food Allergy in Children Aged 3 to 6 Years in Wenzhou and Taizhou Urban Areas

Objective

1. To investigate the status of food allergy among children aged 3 to 6 in Wenzhou and Taizhou urban areas.

2. To obtain the self-reported rate of parents or guardians of food allergy among children aged 3 to 6 in Wenzhou and Taizhou urban areas.

3. To obtain the prevalence of food allergy among children aged 3 to 6 in Wenzhou and Taizhou urban areas by conducting skin prick test (SPT), blood eosinophil (EOS) count, total immunoglobulin E (tIgE) measurement and serum specific IgE (sIgE) determination in children who self-reported food allergy, and conducting the open food challenge (OFC) if it is needed for further diagnosis.

Methods The preschool children aged 3 to 6 from kindergartens in Wenzhou and Taizhou urban areas were selected by cluster sampling and random sampling to conduct a preliminary screening questionnaire. Then telephone interviewe the children who had diseases or problems caused by certain food or certain types of food. Make them finish further food allergy questionnaires, SPT, EOS, tIgE detection, sIgE detection. SPT has 17 kinds of food allergens including milk, egg white, egg yolk, shrimp, crab, wheat, mackerel, perch, cod, peanut, cashew nut, soybean, peach, pineapple, mango, orange and kiwifruit. sIgE has 10 kinds of food allergens including milk, egg white, shrimp, crab, soybean, peanut, wheat, nut mixed group and food mixed group. Children whose results of SPT and/or sIgE didn't meet the diagnostic criteria and children whose results of SPT and sIgE were negative but its history strongly supported food allergy need to conduct OFC. Descriptive analysis and risk factor analysis were carried out on the results, and SPSS 18.0 statistical software was used in statistics analyzation.