Zheng F Y, Chen Q W, Li Z, Gong X W, Wang J D, Yin H
State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 1 Xujiaping, Yanchangbao, Lanzhou 730046, Gansu, China.
State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 1 Xujiaping, Yanchangbao, Lanzhou 730046, Gansu, China.
Res Vet Sci. 2016 Feb;104:146-51. doi: 10.1016/j.rvsc.2015.12.018. Epub 2015 Dec 23.
Bovine ephemeral fever (BEF) is an arthropod-borne viral disease that occurs throughout mainland China. LS11 obtained in the 2011 BEF epidemic was a wild strain, and its virulence and antibody response have never been studied in China. Therefore, the issues were investigated in this work. Experimental cattle were intravenously infected with different doses of BEF virus, and some non-infected cattle were simultaneously monitored. Blood and serum samples were collected from all animals over the course of our study. Infected cattle were challenged for a second time with BEF virus to determine protective period of the antibodies. BEF virus was detected in blood samples from infected cattle, but not in monitored cattle. The neutralizing antibodies (nAbs) against BEFV were easier to be detected and persisted for longer periods in cattle infected with higher doses of BEFV than in those infected with lower doses. When the titer of nAbs was equal to 5 or 6, re-infected cattle still could mount a challenge against BEFV. However, after 3 or 6months, when nAbs were no longer apparent, re-infected cattle displayed typical symptoms of BEF. Our findings indicated that vaccination should be performed once the titer of nAb decreased to 5 or 6.
牛流行热（BEF）是一种在中国大陆广泛传播的节肢动物传播的病毒性疾病。2011年牛流行热疫情中获得的LS11是一株野生毒株，其毒力和抗体反应在中国尚未被研究过。因此，本研究对这些问题进行了调查。对实验牛静脉注射不同剂量的牛流行热病毒，并同时监测一些未感染的牛。在研究过程中从所有动物采集血液和血清样本。用牛流行热病毒对感染牛进行二次攻毒，以确定抗体的保护期。在感染牛的血液样本中检测到牛流行热病毒，但在监测牛中未检测到。与低剂量感染的牛相比，高剂量感染牛更容易检测到抗牛流行热病毒中和抗体（nAbs），且中和抗体持续时间更长。当nAbs滴度等于5或6时，再次感染的牛仍能抵抗牛流行热病毒。然而，3或6个月后，当nAbs不再明显时，再次感染的牛出现了典型的牛流行热症状。我们的研究结果表明，当nAb滴度降至5或6时应进行疫苗接种。
