Kifaro Emmanuel G, Nkangaga Japhet, Joshua Gradson, Sallu Raphael, Yongolo Mmeta, Dautu George, Kasanga Christopher J
Department of Microbiology and Parasitology, Sokoine University of Agriculture.
Onderstepoort J Vet Res. 2014 Apr 23;81(2):E1-5. doi: 10.4102/ojvr.v81i2.717.
Rift Valley fever virus (RVFV) is an acute, zoonotic viral disease caused by a Phlebovirus, which belongs to the Bunyaviridae family. Among livestock, outbreaks of the disease are economically devastating. They are often characterised by large, sweeping abortion storms and have significant mortality in adult livestock. The aim of the current study was to investigate RVFV infection in the Kigoma region, which is nestled under the hills of the western arm of the Great Rift Valley on the edge of Lake Tanganyika, Tanzania. A region-wide serosurvey was conducted on non-vaccinated small ruminants (sheep and goats, n = 411). Sera samples were tested for the presence of anti-RVFV antibodies and viral antigen, using commercial enzyme-linked immunosorbent assay and reverse transcriptase polymerase chain reaction, respectively. The overall past infections were detected in 22 of the 411 animals, 5.4% (Confidence Interval (CI) 95% = 3.5% - 8.1%). The Kigoma rural area recorded the higher seroprevalence of 12.0% (CI 95% = 7.3% - 18.3%; p < 0.0001), followed by Kibondo at 2.3% (CI 95% = 0.5% - 6.5%; p > 0.05) and the Kasulu district at 0.8% (CI 95% = 0.0% - 4.2%; p > 0.05). The prevalence was 12.5% and 4.7% for sheep and goats, respectively. Reverse transcriptase polymerase chain reaction results indicated that only eight samples were found to be positive (n = 63). This study has confirmed, for the first time, the presence of the RVFV in the Kigoma region four years after the 2007 epizootic in Tanzania. The study further suggests that the virus activity exists during the inter-epizootic period, even in regions with no history of RVFV.
裂谷热病毒（RVFV）是一种由白蛉病毒引起的急性人畜共患病毒性疾病，该病毒属于布尼亚病毒科。在牲畜中，该病的爆发会造成经济上的巨大损失。其特征通常是大规模、席卷式的流产风暴，成年牲畜死亡率很高。本研究的目的是调查坦桑尼亚坦噶尼喀湖岸边、东非大裂谷西支山脉脚下的基戈马地区的裂谷热病毒感染情况。对411只未接种疫苗的小反刍动物（绵羊和山羊）进行了全区域血清学调查。血清样本分别使用商业酶联免疫吸附测定法和逆转录聚合酶链反应检测抗RVFV抗体和病毒抗原的存在情况。在411只动物中，有22只检测到既往感染，占5.4%（95%置信区间=3.5%-8.1%）。基戈马农村地区的血清阳性率最高，为12.0%（95%置信区间=7.3%-18.3%；p<0.0001），其次是基邦多，为2.3%（95%置信区间=0.5%-6.5%；p>0.05），卡苏卢区为0.8%（95%置信区间=0.0%-4.2%；p>0.05）。绵羊和山羊的患病率分别为12.5%和4.7%。逆转录聚合酶链反应结果表明，在63份样本中只有8份呈阳性。本研究首次证实，在坦桑尼亚2007年动物疫情爆发四年后，基戈马地区存在裂谷热病毒。该研究进一步表明，即使在没有裂谷热病毒病史的地区，病毒在动物疫情间歇期也有活动。
