Objective: In recent years, the incidence of allergic diseases in China is increasing. With serious influence on the patients' quality of life and even life-threatening, now allergic diseases have become an important public health problem in our country. This survey aimed to obtain a general epidemic outline of children's major allergic diseases, i.e., childhood asthma, allergic rhinitis and eczema in the downtown of Beijing, Chongqing and Guangzhou.
Method: Childhood asthma questionnaire was established by Delphi method based on guidelines for childhood asthma diagnosis and prevention made by Chinese medical association in 2008 with reference to the International Study of Asthma and Allergies in Childhood questionnaire (ISAAC). This study was carried out from Oct. 2008-Mar. 2009, in Beijing, Chongqing and Guangzhou by a multi-stage sampling method, covering a sample of 24 290 children aged 0 - 14 years by a multi-stage sampling method, the population of children surveyed in the downtown of Beijing Chongqing and Guangzhou was 10 372, 9874 and 4072 respectively; of whom males were 5545, 5258, 2159, and females were 4917, 4588, 1877; the ratio of males to females in the three cities were 1.11:1, 1.15:1, 1.15:1; the average age of surveyed children were 7.63, 8.74 and 8.30 years old. All the questionnaire was filled in by the parents of children or other guardian of children.
Result: The self-reported prevalence of asthma in Beijing, Chongqing and Guangzhou was 3.15%, 7.45%, 2.09%, the self-reported prevalence of allergic rhinitis was 14.46%, 20.42%, 7.83%, and the prevalence of eczema was 20.64%, 10.02%, 7.22%. In the survey, asthma combined with allergic rhinitis had the highest rate, 49.54%, 50.14%, 34.83%, respectively in the 3 cities. The self-reported prevalence of asthma and allergic rhinitis was significantly higher in male than female. Besides, the self-reported prevalences of asthma and allergic rhinitis were relatively lower in children under 1 year and over 10 years of age.
Conclusion: The prevalence of asthma, allergic rhinitis and eczema and other allergic diseases in children 0 - 14 years of age in the three cities gradually increased, and the prevalence of allergic diseases in Chongqing was relatively higher.