Institute of Diagnostic Virology, Greifswald-Insel Riems, Germany.
Central Veterinary Research Laboratory, Dubai, United Arab Emirates.
Transbound Emerg Dis. 2020 Nov;67(6):2881-2891. doi: 10.1111/tbed.13660. Epub 2020 Jul 2.
Peste des petits ruminants (PPR) is a fatal disease of small ruminants which has spread rapidly to previously PPR-free countries in recent decades, causing enormous economic losses in the affected regions. Here, two newly emerged PPR virus (PPRV) isolates from India and from the Middle East were tested in an animal trial to analyse their pathogenesis, and to evaluate serological and molecular detection methods. Animals infected with the two different PPRV isolates showed marked differences in clinical manifestation and scoring. The PPRV isolate from India was less virulent than the virus from the Middle East. Commercially available rapid detection methods for PPRV antigen (two Lateral Flow Devices (LFDs) and one antigen ELISA) were evaluated in comparison with a nucleic acid detection method. For this purpose, ocular and nasal swabs were used. Due to the easy non-invasive sampling, faecal samples were also analysed. For all rapid antigen detection methods, a high specificity of 100% was observed independent of the sample matrix and dilution buffers used. Both antigen ELISA and LFD tests showed highest sensitivities for nasal swabs. Here, the detection rate of the antigen ELISA, the LFD-PESTE-TEST and the LFD-ID Rapid-Test was 78%, 75% and 78%, respectively. Ocular swabs were less suitable for antigen detection of PPRV. These results reflect the increased viral load in nasal swabs of PPRV infected goats compared to ocular swabs. The faecal samples were the least suitable for antigen detection. In conclusion, nasal swab samples are the first choice for the antigen and genome detection of PPRV. Nevertheless, based on the excellent diagnostic specificity of the rapid tests, positive results generated with other sample matrices are solid. In contrast, negative test results can be caused on the reduced analytical sensitivity of the rapid antigen tests and must be treated with caution.
小反刍兽疫（PPR）是一种致命的小反刍动物疾病，近几十年来已迅速传播到以前无 PPR 的国家，给受影响地区造成了巨大的经济损失。在这里，我们对来自印度和中东的两种新出现的 PPR 病毒（PPRV）分离株进行了动物试验，以分析其发病机制，并评估血清学和分子检测方法。感染两种不同 PPRV 分离株的动物在临床表现和评分上表现出明显的差异。来自印度的 PPRV 分离株的毒力比来自中东的病毒低。我们对市售的两种 PPRV 抗原快速检测方法（两种侧向流动设备（LFD）和一种抗原 ELISA）与核酸检测方法进行了比较。为此，我们使用了眼部和鼻腔拭子。由于易于非侵入性采样，我们还分析了粪便样本。对于所有快速抗原检测方法，观察到高特异性 100%，与使用的样本基质和稀释缓冲液无关。两种抗原 ELISA 和 LFD 检测均显示出对鼻腔拭子的最高敏感性。在这里，抗原 ELISA、LFD-PESTE-TEST 和 LFD-ID Rapid-Test 的检测率分别为 78%、75%和 78%。眼部拭子不太适合用于检测 PPRV 抗原。这些结果反映了 PPRV 感染山羊鼻腔拭子中的病毒载量高于眼部拭子。粪便样本最不适合用于检测抗原。总之，鼻腔拭子样本是检测 PPRV 抗原和基因组的首选。然而，基于快速检测的优异诊断特异性，其他样本基质产生的阳性结果是可靠的。相比之下，阴性检测结果可能是由于快速抗原检测的分析灵敏度降低造成的，必须谨慎处理。
