Prevalence of sIgE response to allergens in different regions of mainland China
Table 2 displayed detailed data of each allergen in seven regions of mainland China. The chi-square test was applied to test the difference in the prevalence of sensitization to allergens among seven regions. The results showed a significant difference in the prevalence among regions for all 9 allergens except for the mold mix. To show the prevalence results integrated with the map of China, we generated a heatmap of the prevalence of the sIgE response to allergens in different regions (Figure 3). From the figure, we can obtain the distribution of the prevalence of the sIgE response to allergens in different regions of mainland China.
The prevalence patterns of the egg whites and milk in Central China (16.91% and 17.55%, respectively) and East China (14.67% and 15.99%, respectively) and South China (12.23% and 15.16%, respectively) were higher than those in Southwest China, North China and Northeast China (all lower than 9.68%), which means that patients living in eastern, coastal and or southern areas were more sensitive to egg whites and cow’s milk. For crab and shrimp, the prevalence of both sensitization in Southwest China (19.14% and 22.69%, respectively) and South China (17.5% and 19.3%, respectively) was higher than that in the northern regions (North China and Northeast China, which were both lower by 7.19%). House dust mites were the allergen with the highest positive rate in all 7 regions, with the highest in South China (40.79%), followed by East China (36.00%) and Southwest China (32.22%), and the lowest positive rates were found in Northeast China (11.21%). Allergies to German cockroaches had a higher prevalence in southern regions (Southwest China (29.25%), South China (21.67%) and East China (20.85%)) than in northern regions (North China (7.32%) and Northeast China (5.97%)). The prevalence of sIgE responses to dog dander were the highest in North China (8.72%), and the prevalence in the southern regions (3.18~4.14%) was very close to each other.