Ehrlichiosis, caused by Gram-negative bacteria of the genus Ehrlichia, is considered an emerging infectious disease due to the increasing number of reported cases. Symptoms are non-specific and occur within 1 to 2 weeks following the bite of an infected tick. Confirmatory laboratory diagnostic methods vary in sensitivity and specimen requirements, which can lead to delayed diagnosis. PCR testing serves as an efficient approach to Ehrlichia confirmation in the acute stage of illness. Published assays have been effectively used to detect human ehrlichiosis at limit of detections ranging from 10 to 50 genomic copies (GC) of Ehrlichia DNA. With the discovery of new species capable of human infection, we wanted to develop assays that are sensitive and encompass a wide range of Ehrlichia. Here we developed and validated two sensitive and specific real-time PCR assays (PanE1 and PanE2) for the detection of Ehrlichia species, as well as two real-time PCR assays (ECh2 and ECh4) for the detection of Ehrlichia chaffeensis, specifically. The limit of detection was determined to be 10 GC per reaction with 100% confidence, and as little as 1 GC with lower efficiencies. Accuracy was assessed at 100% correlation. Specificity from exclusivity testing demonstrated that neither the Ehrlichia species assays (n = 60), nor the E. chaffeensis specific assays (n = 64) had cross reactivity with near neighbors or environmental bacteria. A positive predictive value of 100% and a negative predictive value of ≥93% was determined by evaluating banked clinical specimens from 62 patients with the assays. These real-time PCR assays are effective tools to detect human Ehrlichia species during the acute stage of illness. Early detection of Ehrlichia infection by these real-time PCR assays can facilitate diagnosis and treatment.

埃立克体病是由埃立克体属革兰氏阴性菌引起的，由于报告的病例数量不断增加，它被认为是一种新出现的传染病。症状是非特异性的，在被感染的蜱叮咬后 1 到 2 周内出现。验证性实验室诊断方法在敏感性和标本要求方面各不相同，这可能导致诊断延迟。PCR 检测是在疾病急性期确认埃立克体的有效方法。发布时间测定法已被有效地用于在检测范围为10至50个基因组拷贝（GC）的极限，以检测人类埃里希体病埃立克体脱氧核糖核酸。随着能够感染人类的​​新物种的发现，我们希望开发灵敏且涵盖范围广泛的埃立克体的检测方法。在这里，我们开发并验证了两种灵敏且特异的实时 PCR 检测方法（PanE1 和 PanE2），用于检测埃立克体属物种，以及两种实时 PCR 检测方法（ECh2 和 ECh4）用于检测埃立克体埃立克体。检测限确定为每个反应 10 次 GC，置信度为 100%，低至 1 次 GC，效率较低。准确度评估为 100% 相关。排他性测试的特异性表明，埃立克体属物种测定 ( n  = 60) 和恰菲埃里希体特定检测 ( n  = 64) 与近邻或环境细菌有交叉反应。100% 的阳性预测值和≥93% 的阴性预测值是通过使用这些检测评估来自 62 名患者的临床样本确定的。这些实时 PCR 检测是在疾病的急性阶段检测人类埃立克体的有效工具。通过这些实时 PCR 检测及早检测埃立克体感染可以促进诊断和治疗。