Elnekave E, Zamir L, Hamd F, Even Tov B, Klement E
Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, POB 12, Rehovot 76100, Israel.
Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, POB 12, Rehovot 76100, Israel; Israeli Veterinary Services, Kanot Local District, Israel.
Prev Vet Med. 2015 Jun 15;120(2):236-240. doi: 10.1016/j.prevetmed.2015.03.011. Epub 2015 Mar 21.
Foot and mouth disease (FMD) is considered one of the most important diseases of cattle. Recurrence of FMD outbreaks in Israel is common, even though routine vaccination of livestock is mandatory and control measures are applied during the outbreaks. Grazing beef herds are occasionally involved in these outbreaks and play an important role in disseminating the disease, due to the large efflux of animals from these herds to feedlots. Nevertheless, the risk factors for the occurrence of FMD among these herds have never been investigated. In 2011, Israel faced a large scale outbreak of serotype O FMD virus, which strongly affected beef cattle. We conducted a case-control study of 44 beef cattle herds grazing in the Golan Heights in order to determine the risk factors for FMDV infection. Data were analyzed using a generalized estimation equation (GEE) with a logit link function. Multivariable analysis was conducted for factors with p-value lower than 0.1 in the univariable analysis. The presence of calves under 6 months of age was found as a significant risk factor for FMDV infection in the univariable analysis (odds ratio (OR)=5.95, confidence intervals of 95% (CI95%)=1.59-22.29, p=0.008). This was also the only variable that remained statistically significant in the multivariable analysis. Herds in which more than 6 months between vaccination of adults and exposure had elapsed were in higher risk, albeit not statistically significant, for the occurrence of FMDV infection (OR=3.29, CI95%=0.83-12.99, p=0.089). The higher probability of infection in herds, which included young calves may be a result of their higher susceptibility due to administration of only one or no vaccine prior to the outbreak. The results of the study thus support increasing the frequency of vaccination of both cows and calves in grazing beef herds. Intensifying surveillance where young calves are abundant may also prove efficient for early detection of infected herds and for mitigating outbreaks of FMDV.
口蹄疫（FMD）被认为是牛最重要的疾病之一。尽管以色列对家畜进行强制常规疫苗接种，并在疫情爆发期间采取控制措施，但口蹄疫疫情在该国反复出现仍很常见。放牧的肉牛群偶尔会卷入这些疫情，并在疾病传播中发挥重要作用，因为这些牛群中有大量动物流向饲养场。然而，这些牛群中口蹄疫发生的风险因素从未得到过调查。2011年，以色列面临O型口蹄疫病毒的大规模疫情，对肉牛造成了严重影响。我们对在戈兰高地放牧的44个肉牛群进行了病例对照研究，以确定口蹄疫病毒感染的风险因素。使用具有logit链接函数的广义估计方程（GEE）对数据进行分析。对单变量分析中p值低于0.1的因素进行多变量分析。在单变量分析中，发现存在6个月龄以下的犊牛是口蹄疫病毒感染的一个重要风险因素（优势比（OR）=5.95，95%置信区间（CI95%）=1.59 - 22.29，p = 0.008）。这也是多变量分析中唯一在统计学上仍具有显著意义的变量。成年牛接种疫苗与接触病毒之间间隔超过6个月的牛群，发生口蹄疫病毒感染的风险更高，尽管在统计学上不显著（OR = 3.29，CI95% = 0.83 - 12.99，p = 0.089）。包含幼龄犊牛的牛群感染概率较高，可能是由于在疫情爆发前只接种了一剂疫苗或未接种疫苗，导致它们易感性较高。因此，该研究结果支持增加放牧肉牛群中母牛和犊牛的疫苗接种频率。在幼龄犊牛数量较多的地方加强监测，也可能被证明有助于早期发现感染牛群并减轻口蹄疫病毒的疫情爆发。
