Riedler J, Eder W, Oberfeld G, Schreuer M
Paediatric Pulmonology, Children's Hospital Salzburg, Austria.
Clin Exp Allergy. 2000 Feb;30(2):194-200. doi: 10.1046/j.1365-2222.2000.00799.x.
In some studies, the prevalence of hay fever and asthma has been found to be lower in children from rural areas than in children from an urban environment. We hypothesized that living on a farm might be protective against development of allergic sensitization and allergic diseases.
In a cross-sectional survey, parents of 2283 children aged 8-10 years from a mostly rural area in Austria answered a standardized questionnaire on allergic diseases and environmental factors. 1137 children performed a skin prick test to seven local allergens.
The prevalence of hay fever (3.1 vs 10.3%, P = 0.0002), asthma (1.1 vs 3.9%, P = 0.017) and a positive skin prick reactivity to at least one of the common local allergens (18.8 vs 32.7%, P = 0. 001) was significantly lower in children living on a farm than in children from a non-farming environment. In a multivariate logistic regression model, adjusting for genetic background, parent education, living and housing conditions and dietary factors did not change the odds ratio for the association of farming and allergic sensitization. Only after including 'regular contact with livestock and poultry' into the model did the odds ratio change significantly (cOR 0.48 95% CI 0.30-0.75 to aOR 0.75 95% CI 0.37-1.52) indicating an association between regular contact with farm animals and reduced risk of atopic sensitization.
Possible explanations for the lower prevalence of hay fever, asthma and allergic sensitization in children living on a farm might be the development of immunotolerance or the stimulation of TH1 cells and suppression of TH2 cells by increased exposure of farm children to microbial antigens in the stables or farmhouses.
在一些研究中，发现农村地区儿童的花粉症和哮喘患病率低于城市环境中的儿童。我们推测生活在农场可能对过敏性致敏和过敏性疾病的发展具有保护作用。
在一项横断面调查中，来自奥地利一个主要为农村地区的2283名8至10岁儿童的父母回答了一份关于过敏性疾病和环境因素的标准化问卷。1137名儿童对七种当地过敏原进行了皮肤点刺试验。
生活在农场的儿童中，花粉症（3.1%对10.3%，P = 0.0002）、哮喘（1.1%对3.9%，P = 0.017）以及对至少一种常见当地过敏原的皮肤点刺反应呈阳性（18.8%对32.7%，P = 0.001）的患病率显著低于非农业环境中的儿童。在多因素逻辑回归模型中，调整遗传背景、父母教育程度、生活和居住条件以及饮食因素后，农场生活与过敏性致敏之间关联的优势比没有变化。只有在将“定期接触家畜和家禽 ”纳入模型后，优势比才发生显著变化（校正优势比0.48，95%可信区间0.30 - 0.75变为调整后优势比0.75，95%可信区间0.37 - 1.52），表明定期接触农场动物与特应性致敏风险降低之间存在关联。
农场儿童花粉症、哮喘和过敏性致敏患病率较低的可能解释是免疫耐受的发展，或者是农场儿童更多地接触畜舍或农舍中的微生物抗原，从而刺激了TH1细胞并抑制了TH2细胞。
