Borel N, Doherr M G, Vretou E, Psarrou E, Thoma R, Pospischil A
Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 268, CH-8057 Zurich, Switzerland.
Prev Vet Med. 2004 Oct 14;65(3-4):205-16. doi: 10.1016/j.prevetmed.2004.08.005.
Our aim was to assess the seroprevalence of Chlamydophila (Cd) abortus (Chlamydia psittaci serotype 1), denoted ovine enzootic abortion (OEA), in the Swiss sheep population. A competitive enzyme-linked immunosorbent assay (cELISA) was adapted for the investigation of pooled serum samples (pool approach) and receiver-operator characteristic (ROC) analysis was applied to define the cut-off of the pool approach. At a cut-off value of 30% inhibition, the flock-level pooled sensitivity and specificity were 92.9% and 97.6% when compared to classifying the flock based on individual-animal samples. Subsequently, sera from 775 randomly selected flocks out of 11 cantons of Switzerland were investigated using the pool approach. The cantons included in the study represented 72% of the Swiss sheep flocks and 76% of Swiss sheep population. Antibodies against Cd. abortus were found in almost 19% (144) of the 775 examined sheep flocks. Test prevalences were adjusted for the imperfect test characteristics using the Rogan-Gladen estimator and Bayesian inference. Seroprevalence was highest (43%) in the canton Graubunden. In the remaining 10 cantons the seroprevalence ranged from 2 to 29%. The cELISA in combination with testing pooled sera and statistical methods for true prevalence estimation provided a good survey tool at lower costs and time when compared to other approaches.
我们的目的是评估瑞士绵羊群体中流产嗜衣原体（Cd）（鹦鹉热衣原体血清型1，即绵羊地方性流产病原体）的血清阳性率。我们采用了一种竞争性酶联免疫吸附测定法（cELISA）来检测混合血清样本（混合样本法），并应用受试者工作特征（ROC）分析来确定混合样本法的临界值。与基于个体动物样本对羊群进行分类相比，在抑制率临界值为30%时，羊群水平的混合样本敏感性和特异性分别为92.9%和97.6%。随后，我们使用混合样本法对瑞士11个州中随机选取的775个羊群的血清进行了检测。纳入研究的州代表了瑞士72%的绵羊群和76%的绵羊数量。在775个受检羊群中，近19%（144个）检测出抗流产嗜衣原体抗体。使用罗根 - 格拉登估计器和贝叶斯推断法对检测的不完美特征进行了校正，以计算检测患病率。格劳宾登州的血清阳性率最高（43%）。在其余10个州，血清阳性率在2%至29%之间。与其他方法相比，cELISA结合检测混合血清以及用于真实患病率估计的统计方法，以较低的成本和时间提供了一种良好的调查工具。
