Department of Virology, Veterinary Faculty, Necmettin Erbakan University, Ereğli, 42310 Konya, Turkey.
Prev Vet Med. 2023 Apr;213:105871. doi: 10.1016/j.prevetmed.2023.105871. Epub 2023 Feb 13.
Bluetongue (BT) is an endemic disease of small ruminants in Turkey, and it has substantial socio-economic impact at national level. To reduce this impact, vaccination has been used for the control of BT but sporadic outbreaks have been reported. Although sheep and goat farming plays an important role in rural communities, little is known about the BT epidemiological situation in small ruminants in Turkey. Therefore, this study aimed to estimate the seroprevalence of the bluetongue virus (BTV) and to identify the potential risk factors associated with BTV seropositivity in small ruminants. This study was conducted in the Antalya Province in the Mediterranean region of Turkey, from June 2018 to June 2019. A total of 1026 blood samples, from clinically healthy goats (n = 517) and sheep (n = 509), obtained from randomly selected unvaccinated flocks (n = 100) were tested for BTV anti-VP7 antibodies by using a competitive enzyme linked immunosorbent assay test. A questionnaire was administered to the flock owners to obtain data related to sampled flocks and animals. At the animal level, the true prevalence of BTV antibodies was 74.2% (n = 651/1026, 95% CI = 70.7-77.7) with 85.3% (n = 370/509, 95% CI = 80.6-89.9) seropositive sheep and 63.3% (n = 281/517, 95% CI = 58.2-68.4) seropositive goats. The true flock-level seroprevalence of BTV was higher in goats (100.0%, 95% CI = 92.8-100.0) than in sheep (98.8%, 95% CI = 86.6-100.0). The intra-flock seroprevalence within seropositive flocks varied between 36.4% and 100%, with a mean value of 85.5% and 61.9% in sheep and goat flocks, respectively. The logistic regression model revealed that odds of seropositivity for sheep were significantly higher in female animals (OR: 1.8, 95% CI = 1.1-2.9), animals older than 24 months old (OR: 5.8, 95% CI = 3.1-10.8), Pirlak breed (OR: 3.3, 95% CI = 1.1-10.0) and Merino breed (OR: 4.9, 95% CI = 1.6-14.9), whereas for goats, it was higher in female animals (OR: 1.7, 95% CI = 1.0-2.6), animals older than 24 months old (OR: 4.2, 95% CI = 2.7-6.6) and Hair breed (OR: 5.6, 95% CI = 2.8-10.9). The use of insecticides was identified as a protective factor. The present study revealed that BTV infection is widespread in sheep and goats in the Antalya Province. It is recommended to implement biosecurity measures in flocks and use insecticides to mitigate the spread of infection and contact between hosts and vectors.
土耳其的小反刍动物蓝舌病（BT）是一种地方性疾病，在国家层面上具有重大的社会经济影响。为了降低这种影响，已经使用疫苗接种来控制 BT，但仍有散发病例报告。尽管绵羊和山羊养殖在农村社区中发挥着重要作用，但对土耳其小反刍动物 BT 的流行病学情况知之甚少。因此，本研究旨在估计蓝舌病毒（BTV）的血清流行率，并确定与 BTV 血清阳性相关的潜在风险因素。本研究在土耳其地中海地区的安塔利亚省进行，时间为 2018 年 6 月至 2019 年 6 月。从随机选择的未接种羊群（n=100）中采集了 1026 份来自临床健康山羊（n=517）和绵羊（n=509）的血液样本，使用竞争酶联免疫吸附试验检测 BTV 抗-VP7 抗体。向羊群所有者发放了一份问卷，以获取与采样羊群和动物相关的数据。在动物水平上，BTV 抗体的真实流行率为 74.2%（n=651/1026，95%CI=70.7-77.7），绵羊的血清阳性率为 85.3%（n=370/509，95%CI=80.6-89.9），山羊的血清阳性率为 63.3%（n=281/517，95%CI=58.2-68.4）。BTV 在山羊中的真实群体血清流行率（100.0%，95%CI=92.8-100.0）高于绵羊（98.8%，95%CI=86.6-100.0）。在血清阳性的羊群中，羊群内的血清流行率在 36.4%至 100%之间不等，绵羊和山羊的平均血清阳性率分别为 85.5%和 61.9%。逻辑回归模型显示，绵羊的血清阳性率在雌性动物（OR：1.8，95%CI=1.1-2.9）、24 个月以上的动物（OR：5.8，95%CI=3.1-10.8）、Pirlak 品种（OR：3.3，95%CI=1.1-10.0）和 Merino 品种（OR：4.9，95%CI=1.6-14.9）中显著更高，而对于山羊，在雌性动物（OR：1.7，95%CI=1.0-2.6）、24 个月以上的动物（OR：4.2，95%CI=2.7-6.6）和 Hair 品种（OR：5.6，95%CI=2.8-10.9）中更高。使用杀虫剂被确定为保护因素。本研究表明，BTV 感染在安塔利亚省的绵羊和山羊中广泛流行。建议在羊群中实施生物安全措施，并使用杀虫剂来减轻感染的传播和宿主与媒介之间的接触。
