Figure 1. Heatmap for the prevalence of positive SIgE tests for House dust mite (a), German cockroach (b), Tree pollen mix (c), Dog dander (d), Egg whites (e), Cow’s milk (f), Crab (g), Shrimp (h) in different regions. The positive rate (%) and the total number of each case were marked. The total number of the cases in Northwest China for all 9 allergens and in North China for tx4 were less than 50, so the prevalence in those regions was not calculated (NA).