职业接触生猪人群戊型肝炎病毒感染的随访检测

One-year follow-up study on the prevalence of antiI-hepatitis e ivrus antibody among persons who work with swine

目的评估职业接触生猪者感染戊型肝炎病毒的危险程度。方法选择从事生猪饲养、屠宰、集市销售和兽医等4个职业接触生猪人群作为研究对象,进行一年的随访。随访开始和结束时,分别采集静脉血5ml,按4倍的比例倍比稀释进行抗HEV-IgG半定量检测,同一研究对象的血清同时进行平行检测。用单因素和多因素Logistic回归方法分析结果及其危险因素。结果随访未发现急性戊型肝炎病例。两次横断面调查结果显示,职业人群抗HEV-IgG阳性率分别为68.99%与70.30%。11.36%（5/44,95%CI：3.79-24.56%）的人抗体阳转,是一般人群的2.64倍（95%CI：1.13-6.20）。在随访开始时抗体阳性的人群中,18.18%（24/132）的人抗体呈4倍以上增高;2.27%（3/132）的人抗体阴转,12.12%（16/132）的人抗体有4倍以上下降;抗体阳性但抗体水平基本不变的占67.42%（89/132）。随着年龄的增长,感染率有明显的增高趋势。结论职业接触生猪与戊肝感染有关,个人不良卫生习惯可增加感染的风险。

Swine was considered to be the principle source of human HEV infection in Eastern China. A cross-sectional survey was performed in both 2005 and 2006 respectively in the same swine-related population （including swine farmers, butchers, meatmen and veterinarians） with a structural questionnaire to explore the risk for infection during occupational contact with swine. Simultaneously, 5 ml of periodic venous blood was collected with informed consent. The reactivity of IgG anti- HEV was investigated serologically and determined in semi-quantification by 4-fold dilution with commercial HEV ELISA kits. HEV infection in the present study was validated by positive conversion or increase by ≥4-fold of IgG anti-HEV level. The serum sampled from the same person in both 2005 and 2006 were tested in parallel to avoid possible bias. The seroprevalence of IgG anti-HEV in the swine-related population was relatively stable for both calendar years （68.99% vs. 70.30%）. No clinical case of HEV infection was recorded during one-year follow-up. 11.4% （5/44, 95%CI ： 3.79-24.56%） of IgG anti-HEV-negative persons in 2005 got positive conversion, which was higher than that of general population （RR= 2. 64, 95% CI： 1.13- 6.20）. In the 132 anti-HEV-positive persons in 2005, the proportions of those who boosted by ≥4-fold boost, altered within 4-fold, decreased by ≥4-fold and got negative conversion in the reactivity of IgG anti-HEV were 18. 18% （24）, 67.42% （89）, 12.12 % （16） and 2.27 % （3） after one-year follow-up respectively. The experience of working with swine was associated with HEV infection significantly. The risk of HEV infection was larger in the elder persons than in the younger ones in the seropositire population through multivariate logistic regression analysis. And poor sanitary habits was another risk factor of HEV infection among swine-related population.