Garrido Haro Ana Dolores, Barrionuevo Samaniego Margoth Yolanda, Moreno-Caballeros Paola, Burbano-Enríquez Alexandra, Salas Torres Verónica Alexandra, Galante Mulki María Cristina, Wielick Constance, Ron-Román Jorge, Saegerman Claude
Agrocalidad Tumbaco, Quito 170903, Ecuador.
Research Unit of Epidemiology and Risk Analysis Applied to Veterinary Science (UREAR-ULg), Fundamental and Applied Research for Animals & Health (FARAH) Center, Faculty of Veterinary Medicine, University of Liege, 4000 Liège, Belgium.
Microorganisms. 2025 Jan 2;13(1):69. doi: 10.3390/microorganisms13010069.
Bovine brucellosis (bB) is a zoonosis mainly caused by the species in cattle. Bovine brucellosis can present with either a range of clinical symptoms, including spontaneous abortions in the last trimester of pregnancy, retained fetal membranes, and decreased milk production, or it can be asymptomatic. In Ecuador, vaccination against bB with S19 and/or RB51 is not mandatory and is the responsibility of the farmer. As serology is a convenient method for detecting antibodies against , evaluating the diagnostic performance and discriminative ability of such tests in various epidemiological settings is required. To estimate and compare the diagnostic sensitivity (Se) and specificity (Sp) of two screening tests, a new competitive (cELISA) and an indirect ELISA based on a new synthetic antigen (iELISA), a randomized, stratified, cross-sectional, serological survey was performed on the cattle population (3299 bovine sera from 223 farms) in continental Ecuador. A Bayesian approach was used to evaluate the two tests by estimating their respective diagnostic Se and Sp, as well as the true prevalence of bB in different sub-populations (non-vaccinated, vaccinated with S19 or RB51). The Se of both tests was similar across Bayesian models, with values around 94%. In contrast, the Sp of the iELISA, ranging between 97 and 98%, was significantly higher than that of the cELISA, which was approximately 94-95%. The true prevalence of bB was 1.63% (95% CrI: 0.56-2.54) in non-vaccinated cattle, decreased to 0.97% (95% CrI: 0.005-2.54) in S19-vaccinated cattle and was 2.75% (95% CrI: 0.50-5.32) in RB51-vaccinated cattle. The results of this study suggest that, with similar Se and higher Sp, the iELISA based on an innovative synthetic antigen (which is more standardizable) should be recommended as a possible screening test for bB in Ecuador. Also, the proposed approach suggests insights into the quality of the vaccination campaign and highlights the need for refining the Ecuadorian national brucellosis control program.
牛布鲁氏菌病（bB）是一种主要由牛体内的特定菌种引起的人畜共患病。牛布鲁氏菌病可能表现出一系列临床症状，包括妊娠晚期的自然流产、胎膜滞留和产奶量下降，也可能没有症状。在厄瓜多尔，使用S19和/或RB51疫苗对牛布鲁氏菌病进行疫苗接种并非强制要求，而是由养殖户自行负责。由于血清学检测是检测针对[相关病原体]抗体的便捷方法，因此需要评估此类检测在各种流行病学环境中的诊断性能和鉴别能力。为了估计和比较两种筛查检测方法——一种基于新合成抗原的新型竞争酶联免疫吸附测定法（cELISA）和间接酶联免疫吸附测定法（iELISA）——的诊断敏感性（Se）和特异性（Sp），对厄瓜多尔大陆的牛群（来自223个养殖场的3299份牛血清）进行了一项随机、分层、横断面血清学调查。采用贝叶斯方法通过估计各自的诊断Se和Sp以及不同亚群（未接种疫苗、接种S19或RB51疫苗）中牛布鲁氏菌病的真实患病率来评估这两种检测方法。在不同的贝叶斯模型中，两种检测方法的Se相似，约为94%。相比之下，iELISA的Sp在97%至98%之间，显著高于cELISA的Sp，后者约为94% - 95%。未接种疫苗的牛中牛布鲁氏菌病的真实患病率为1.63%（95%可信区间：0.56 - 2.54），接种S19疫苗的牛中患病率降至0.97%（95%可信区间：0.005 - 2.54），接种RB51疫苗的牛中患病率为2.75%（95%可信区间：0.50 - 5.32）。本研究结果表明，基于创新合成抗原（更具标准化）的iELISA具有相似的Se和更高的Sp，应推荐作为厄瓜多尔牛布鲁氏菌病可能的筛查检测方法。此外，所提出的方法为疫苗接种活动的质量提供了见解，并突出了完善厄瓜多尔国家布鲁氏菌病控制计划的必要性。
