四川省达州市山羊场布鲁氏菌感染风险因素病例对照研究

Case-control Study on Herd-level of Risk Factors Associated with Goat Brucellosis in Dazhou City of Sichuan Province

为了解四川省达州市山羊场布鲁氏菌病传播的风险因素,根据阳性养殖场分布情况,采用病例对照研究的方法,在全市6个区(县)的58个阳性场(病例)和387个阴性场(对照)进行问卷调查,对养殖场基本情况、饲养管理状况、生物安全措施等方面的25项风险因素进行单因素分析、Pearson相关性检验和多因素Logistic回归分析,同时构建Logistic回归方程,计算模型的预测概率并建立ROC曲线。结果显示:该市羊场感染布鲁氏菌的风险因素为:"养殖场存栏量在50头以上"(OR=9.08,95%CI:2.91~28.39,P<0.01);"养殖场启用年限在2012年前"(OR=12.57,95%CI:3.69~42.85,P<0.01);"养殖场近1年内引入过羊只"(OR=9.11,95%CI:1.08~77.29,P=0.04);"从达州市以外地区引羊"(OR=19.30,95%CI:1.94~192.41,P=0.01);"新购入羊只不隔离直接混群"(OR=6.78,95%CI:1.33~34.45,P=0.02);"临产母羊不隔离饲养"(OR=5.63,95%CI:1.61~19.72,P=0.01)。拟合回归模型的ROC曲线下面积为92.6%(95%CI:88.9%~96.4%),说明该模型预测羊场是否感染布鲁氏菌的能力较好。研究结果表明,达州市山羊场感染布鲁氏菌的主要风险因素为对外引羊,以及养殖场户生物安全意识和布鲁氏菌病认知度较差。这提示相关部门应重点加强羊只移动的检疫监管,积极对养殖场户开展布鲁氏菌病宣传干预。

In order to recognize the risk factors of goat brucellosis transmission in Dazhou City of Sichuan Province,according to the distribution of brucellosis-positive goat farms and adopting the case-control study method,a total of 58 brucellosis-positive farms（cases）and 387 negative farms in 6 districts（counties）were investigated by questionnaires.Then single factor analysis,Pearson＇s correlations and multi-factor regression analysis were carried out towards 25 risk factors including basic conditions of the farm,feeding and management status,bio-safety measures and others.Meanwhile,the logistic regression equation was constructed,the predicted probabilities were calculated,and the ROC curves were also built.Results showed that,the risk factors of brucellosis in goat farms of Dazhou City were ：the number of goats in the farm was above 50（OR=9.08,95%CI ：2.91~28.39,P0.01）,the farm was put into use before the year of 2012（OR=12.57,95%CI：3.69~42.85,P0.01）,the farm had introduced goats within one year（OR=9.11,95%CI：1.08~77.29,P=0.04）,some goats were introduced from areas outside of Dazhou（OR=19.30,95%CI ：1.94~192.41,P=0.01）,the newly purchased goats were mixed directly without isolation and quarantine（OR=6.78,95%CI ：1.33~34.45,P=0.02）,the parturient goats weren＇t isolated（OR=5.63,95%CI ：1.61~19.72,P=0.01）.The area under the ROC curve of the fitted regression model was 92.6%（95%CI ：88.9%~96.4%）,indicating the model had a good ability to predict whether the farm was infected by brucellosis.Results showed that,the main risk factor of brucellosis infection was introducing goats from areas outside of Dazhou City,as well as the poor awareness and recognition of the farmers in aspects of bio-safety and brucellosis,hence the relevant departments should focus on strengthening inspection and supervision towards goats with frequent movements,and the publicity and intervention of brucellosis should be actively carried out.