Plague Unit, Institut Pasteur de Madagascar, Antananarivo, 101, Madagascar.
Epidemiology and Clinical Research Unit, Institut Pasteur de Madagascar, Antananarivo, 101, Madagascar.
BMC Infect Dis. 2020 Jan 30;20(1):90. doi: 10.1186/s12879-020-4812-7.
Plague is a highly fatal disease caused by Yersinia pestis. Late diagnosis hampers disease outcome and effectiveness of control measures, induces death and disease spread. Advance on its diagnosis was the use of lateral flow rapid diagnostic test (RDT).
We assessed the performance of the plague RDT based on Y. pestis F1 antigen detection more than 15 years after its deployment in Madagascar. We compared the RDT with bacteriological culture results, using data from plague notified cases collected during the periods for which both tests were performed independently and systematically.
Used with bubonic plague (BP) patient samples, RDTs had a sensitivity of 100% (95% CI: 99.7-100%), a specificity of 67% (95% CI: 64-70%) with a good agreement between bacteriology and RDT results (86%; κ = 0.70, 95% CI 0.67-0.73). For pneumonic plague (PP), RDT had a sensitivity of 100% (95% CI: 91-100%) and a specificity of 59% (95% CI: 49-68%) and concordance between the bacteriological and plague RDT results was moderate (70%; κ = 0.43, 95% CI 0.32-0.55). Analysis focusing on the 2017-2018 plague season including the unprecedented epidemic of PP showed that RDT used on BP samples still had a sensitivity of 100% (95% CI: 85-100%) and a specificity of 82% (95% CI: 48-98%) with a very good agreement with bacteriology 94% (κ = 0.86, 95% CI 0.67-1); for PP samples, concordance between the bacteriological and plague RDT results was poor (61%; κ = - 0.03, 95% CI -0.17 - 0.10).
RDT performance appeared to be similar for the diagnosis of BP and PP except during the 2017 PP epidemic where RDT performance was low. This RDT, with its good sensitivity on both plague clinical forms during a normal plague season, remained a potential test for alert. Particularly for BP, it may be of great value in the decision process for the initiation of therapy. However, for PP, RDT may deliver false negative results due to inconsistent sample quality. Plague diagnosis could be improved through the development of next generation of RDTs.
鼠疫是由鼠疫耶尔森菌引起的一种高致命性疾病。延迟诊断会影响疾病的预后和控制措施的效果，导致死亡和疾病传播。鼠疫诊断方法的进步是基于鼠疫耶尔森菌 F1 抗原检测的侧向流动快速诊断检测（RDT）。
我们评估了 15 年多后在马达加斯加部署的鼠疫 RDT 的性能。我们将 RDT 与细菌培养结果进行了比较，使用了在这两种检测独立和系统进行的时期内收集的鼠疫报告病例的数据。
用于检测腺鼠疫（BP）患者样本时，RDT 的灵敏度为 100%（95%置信区间：99.7-100%），特异性为 67%（95%置信区间：64-70%），细菌学和 RDT 结果之间具有良好的一致性（86%；κ=0.70，95%置信区间 0.67-0.73）。对于肺鼠疫（PP），RDT 的灵敏度为 100%（95%置信区间：91-100%），特异性为 59%（95%置信区间：49-68%），细菌学和鼠疫 RDT 结果之间的一致性为中等（70%；κ=0.43，95%置信区间 0.32-0.55）。针对包括 PP 前所未有疫情在内的 2017-2018 年鼠疫季节的分析表明，用于 BP 样本的 RDT 仍具有 100%的灵敏度（95%置信区间：85-100%）和 82%的特异性（95%置信区间：48-98%），与细菌学具有极好的一致性 94%（κ=0.86，95%置信区间 0.67-1）；对于 PP 样本，细菌学和鼠疫 RDT 结果之间的一致性较差（61%；κ= -0.03，95%置信区间 -0.17-0.10）。
RDT 的性能对于 BP 和 PP 的诊断似乎相似，除了在 2017 年 PP 疫情期间 RDT 的性能较低。这种 RDT 在正常鼠疫季节对两种鼠疫临床形式均具有良好的灵敏度，仍然是一种潜在的警报检测方法。特别是对于 BP，它可能在启动治疗的决策过程中具有重要价值。然而，对于 PP，由于样本质量不一致，RDT 可能会产生假阴性结果。通过开发下一代 RDT 可以提高鼠疫诊断水平。
