Division of Veterinary Epidemiology and Economics, Institute of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159c, 02-776 Warsaw, Poland.
Division of Veterinary Epidemiology and Economics, Institute of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159c, 02-776 Warsaw, Poland.
Prev Vet Med. 2023 Apr;213:105885. doi: 10.1016/j.prevetmed.2023.105885. Epub 2023 Feb 24.
A large-scale study was carried out in a Polish goat population in 2014-2022 to determine the herd-level (between-herd) and within-herd seroprevalence of small ruminant lentivirus (SRLV) infection. A total of 8354 adult goats (aged >1 year) from 165 herds located in various regions of Poland were serologically tested using a commercial ELISA. One hundred twenty eight herds were randomly selected while 37 were enrolled based on convenience non-random sampling. At least 1 seropositive result was obtained in 103 / 165 herds. For all these herds the probability that they were truly positive (herd-level positive predictive value) was calculated. It was ≥ 90% in 91 seropositive herds and 73% to < 90% in 12 herds in which only 1-4 goats were seropositive (22 goats in total). The seropositive goats in the latter herds were retested using a different commercial ELISA and 14 goats (9 males and 5 females) from 9 herds were confirmed to be seropositive (serial testing). The true herd-level seroprevalence was estimated at 61% (95% confidence interval [CI 95%]: 53%-68%). It differed significantly between herd size classes (p = 0.003): the highest prevalences were found in the medium (51 - 100 adult goats) and large herds (>100 adult goats) - 72% (CI 95%: 56-84%) and 86% (CI 95%: 67%-95%), respectively, while prevalences in very small (≤ 20 adult goats) and small herds (21 - 50 adult goats) were 46% (CI 95%: 34%-59%) and 57% (CI 95%: 43%-70%), respectively. The true herd-level seroprevalence differed significantly also between geographical regions of Poland (p = 0.003), with the highest values in the north-western and the lowest in the southern region of the country. The true within-herd seroprevalence estimated using a Bayesian approach ranged from 0.7% to 100% with the median (IQR) of 42% (17%-84%), and did not vary significantly between herd size classes (p = 0.393) or geographical regions of Poland (p = 0.570). Concluding, SRLV infection is widespread in the Polish goat population, the north-western region of Poland is most extensively infected, and herds counting > 50 adult goats are more often infected.
2014 年至 2022 年，在波兰的一个山羊群体中进行了一项大规模研究，以确定小反刍动物慢病毒（SRLV）感染的群体水平（群体间）和群体内血清流行率。使用商业 ELISA 对来自波兰各地 165 个不同地区的 8354 只成年山羊（年龄> 1 岁）进行了血清学检测。随机选择了 128 个群体，同时根据便利非随机抽样选择了 37 个群体。在 103/165 个群体中至少获得了 1 个阳性结果。对于所有这些群体，都计算了它们真正阳性的概率（群体水平阳性预测值）。在 91 个血清阳性群体中，≥90%的概率为 91%，而在 12 个群体中，只有 1-4 只山羊呈血清阳性（总共 22 只山羊），其概率为 73%-<90%。对来自这些群体的血清阳性山羊使用不同的商业 ELISA 进行了重复检测，来自 9 个群体的 14 只山羊（9 只雄性和 5 只雌性）被确认为血清阳性（连续检测）。群体水平的真实血清流行率估计为 61%（95%置信区间 [95%CI]：53%-68%）。它在群体规模类别之间有显著差异（p=0.003）：在中等（51-100 只成年山羊）和大型群体（>100 只成年山羊）中发现的流行率最高，分别为 72%（95%CI：56%-84%）和 86%（95%CI：67%-95%），而在非常小的（≤20 只成年山羊）和小群体（21-50 只成年山羊）中分别为 46%（95%CI：34%-59%）和 57%（95%CI：43%-70%）。在波兰的不同地理区域之间，群体水平的真实血清流行率也有显著差异（p=0.003），西北部地区的流行率最高，南部地区的流行率最低。使用贝叶斯方法估计的真实群体内血清流行率范围为 0.7%至 100%，中位数（IQR）为 42%（17%-84%），在群体规模类别（p=0.393）或波兰地理区域（p=0.570）之间没有显著差异。总之，SRLV 感染在波兰山羊群体中广泛存在，波兰西北部地区感染最为广泛，存栏>50 只成年山羊的群体更常感染。
