[Epidemiological investigation on allergic diseases related to animal dander of cats, dogs and horses].

A multicenter Chinese mainland survey was conducted to investigate the sensitization distribution characteristics of cat, dog and horse dander in patients with allergic diseases, so as to provide clinicians with epidemiological data of common animal allergens and useful information for the prevention and treatment of allergies in cats, dogs and horses. The epidemiological investigation and design was adopted. This study is based on the national epidemiological survey of allergic diseases led by the first affiliated Hospital of Guangzhou Medical University. From January to December in 2021, a total of 2 122 patients diagnosed with allergic diseases were included in the outpatient department of respiratory department/pediatrics/allergy department of 14 units such as the First Affiliated Hospital of Guangzhou Medical University, and 222 healthy subjects were included as controls from the physical examination center of the above units in the same period. All the subjects filled out the allergic disease questionnaire under the guidance of doctors, and the allergen-specific immunoglobulin E (sIgE) of cats, dogs and horses of all subjects were detected by magnetic particle chemiluminescence system. The epidemiological characteristics of three animal allergens in different diseases, ages and regions were analyzed. Chi square test was used to analyze the frequency difference between groups, test or Mann Whitney test was used to test the distribution difference between two groups, and one-way ANOVA or Kruskal Wallis test was used to compare the distribution difference between multiple groups. Bar chart, Venn-plot and radar chart were drawn to show the sensitization distribution characteristics. A small number of missing values caused by subjects' omission have been excluded during the analysis. The 2 122 patients with allergic diseases were 57.35% male (1 217/2 122) and 40.95% female (869/2 122), and 1.70% (36/2 122) patients had loss of gender information. The age of patients with allergic diseases was 9.0 (6.0, 28.0) years, while that of healthy controls was 29.0 (13.0, 39.0) years old, and there were 1.7% (36/2 122) and 0.9% (2/222) subjects with missing age information, respectively. The proportion of caesarean section in allergic patients was significantly higher than that in healthy controls (31.4% 17.6%,χ=16.582,<0.001) [2.5% (54/2 122) of the patient group and 5.4% (12/222) of the control group had missing birth mode information], and the proportion of patients with allergic diseases who reported that both parents had allergic diseases was significantly higher than that of the control group (35.7% 9.5%, χ=65.171,<0.001). Patients with allergic diseases are mainly school-age (6-12 years old) and adolescents (12-18 years old). 16.4% of patients with allergic diseases were sensitized to cat dander, 10% and 6% to dog and horse dander. The sensitization rate of cat dander in patients with rhinitis, asthma, conjunctivitis, food allergy and atopic dermatitis was the highest (16.4%-21.6%), followed by dog dander (10.2%-15.2%). The prevalence of allergic rhinitis was the highest among different animal sensitized populations. The proportion of cat, dog and horse allergens sensitized at the same time is between 10%-15%, and the proportion of any two or more animal dander sensitized at the same time is about 45%. Animal allergens are associated with respiratory allergic diseases, especially allergic rhinitis with allergic conjunctivitis. There were significant differences in the distribution of positive rates of three animal allergens in different regions, and the highest positive rate of cat dander was found in all provinces of the country. The sensitization rate of animal dander allergens increased significantly, and the highest was in children and adolescents. Cat dander is the most common animal allergen, followed by dog. Different animals show obvious cross or common sensitization due to their high homology.