Miyama Takeshi, Watanabe Eiji, Ogata Yoshimi, Urushiyama Yoshiro, Kawahara Naoya, Makita Kohei
Veterinary Epidemiology Unit, Division of Health and Environment Sciences, Graduate School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai Midorimachi, Ebetsu, Hokkaido 069-8501, Japan; Yamagata Prefecture Agricultural Mutual Aid Association, 1333 Koseki, Tendo, Yamagata, 994-8511, Japan.
Yamagata Prefecture Agricultural Mutual Aid Association, 1333 Koseki, Tendo, Yamagata, 994-8511, Japan.
Prev Vet Med. 2018 Jan 1;149:15-20. doi: 10.1016/j.prevetmed.2017.11.008. Epub 2017 Nov 7.
A cross-sectional study was designed to generate information on the herd level prevalence and the risk factors for Leptospira serovar Hardjo (L. Hardjo) in Yamagata, the southern Tohoku, Japan. Bulk tank milk samples from 109 dairy herds were used to test the herd level sero-prevalence of L. Hardjo using a commercial ELISA kit, which detects both L. interrogans serovar Hardjo and L. borgpetersenii serovar Hardjo. A questionnaire survey was conducted at the sampled farms, and univariable and multivariable analyses were performed. Spatial clustering of L. Hardjo at the herd level was examined using spatial scan statistics. Seventy-one herds were found to be positive for L. Hardjo, and the apparent herd prevalence was 65.1% (95% CI: 56.2-74.1%). The risk factors for sero-positivity were larger herd size (p=0.004) and cows with a history of staying in Hokkaido (p <0.001). The spatial scan statistic detected a most likely cluster (relative risk=1.87, log likelihood ratio=9.93, radius=13.70km, p<0.01) in the southern part of the study area where there are large herd sizes and farm density is high. This study revealed that L. Hardjo is prevalent throughout Yamagata, and large scale herd owners introducing cows from Hokkaido in particular should be aware of the risk of infection.
一项横断面研究旨在获取有关日本东北南部山形县钩端螺旋体Hardjo血清型（L. Hardjo）的畜群水平患病率及其风险因素的信息。使用来自109个奶牛场的散装罐牛奶样本，通过一种商业ELISA试剂盒检测L. Hardjo的畜群水平血清阳性率，该试剂盒可检测问号钩端螺旋体Hardjo血清型和博氏钩端螺旋体Hardjo血清型。在抽样农场进行了问卷调查，并进行了单变量和多变量分析。使用空间扫描统计方法检查了L. Hardjo在畜群水平上的空间聚集情况。发现71个畜群L. Hardjo呈阳性，表观畜群患病率为65.1%（95%可信区间：56.2 - 74.1%）。血清阳性的风险因素是畜群规模较大（p = 0.004）和有在北海道停留史的奶牛（p < 0.001）。空间扫描统计在研究区域南部检测到一个最可能的聚集区（相对风险 = 1.87，对数似然比 = 9.93，半径 = 13.70公里，p < 0.01），该区域畜群规模大且农场密度高。这项研究表明，L. Hardjo在山形县普遍存在，特别是从北海道引进奶牛的大规模畜群所有者应意识到感染风险。
