Laboratory of Infectious Animal Diseases, Zoonosis and Sanitary Regulation, Institution of Agricultural Research and Higher Education, Univ. Manouba, National School of Veterinary Medicine of Sidi Thabet, 2020, Sidi Thabet, Tunisia.
Laboratory of Parasitology, Institution of Agricultural Research and Higher Education, Univ. Manouba, National School of Veterinary Medicine of Sidi Thabet, 2020, Sidi Thabet, Tunisia.
BMC Vet Res. 2020 Nov 12;16(1):441. doi: 10.1186/s12917-020-02651-6.
Tick-borne encephalitis virus (TBEv) is a flavivirus that circulates in a complex cycle involving small mammals as amplifying hosts and ticks as vectors and reservoirs. The current study aimed to investigate the presence of TBEv in Tunisian sheep. A sample of 263 adult sheep were selected from 6 localities where Ixodes ricinus is well established. Sera were screened using ELISA for TBEv IgG detection, then the doubtful and positive sera were tested by the seroneutralisation test (SNT) and screened for West Nile Virus (WNv) IgG for cross-reaction assessment.
The ELISA for TBEv IgG detected one positive serum and 17 borderlines. The SNT showed one positive serum among the 18 tested, giving an overall antibody prevalence of 0.38% (95% CI = 0.07-2.12%). All but one serum tested negative to WNv ELISA. None of the sheep farmers reported neurological signs among sheep or humans in their households.
The results may indicate the circulation of TBEv for the first time in Tunisia and in North Africa. Further studies based on either virus isolation or RNA detection, are needed to confirm the presence of TBEv in North Africa.
蜱传脑炎病毒（TBEv）是一种黄病毒，在涉及小型哺乳动物作为扩增宿主、蜱作为媒介和储存宿主的复杂循环中传播。本研究旨在调查突尼斯绵羊中是否存在 TBEv。从伊氏锥虫（Ixodes ricinus）广泛存在的 6 个地点中选择了 263 只成年绵羊作为样本。使用 ELISA 检测 TBEv IgG 来筛选血清，然后用血清中和试验（SNT）检测可疑和阳性血清，并筛查西尼罗河病毒（WNv）IgG 以评估交叉反应。
ELISA 检测 TBEv IgG 检测到 1 份阳性血清和 17 份边界血清。SNT 检测到 18 份血清中有 1 份阳性血清，总抗体流行率为 0.38%（95%CI=0.07-2.12%）。除了 1 份血清外，所有血清对 WNv ELISA 均为阴性。没有一位绵羊饲养员报告其家中的绵羊或人类有神经症状。
这些结果可能首次表明 TBEv 在突尼斯和北非传播。需要进一步进行基于病毒分离或 RNA 检测的研究，以确认 TBEv 在北非的存在。
