The rotating-crystal magneto-optical detection (RMOD) method has been developed for the rapid and quantitative diagnosis of malaria and tested systematically on various malaria infection models. Very recently, an extended field trial in a high-transmission region of Papua New Guinea demonstrated its great potential for detecting malaria infections, in particular Plasmodium vivax. In the present small-scale field test, carried out in a low-transmission area of Thailand, RMOD confirmed malaria in all samples found to be infected with Plasmodium vivax by microscopy, our reference method. Moreover, the magneto-optical signal for this sample set was typically 1–3 orders of magnitude higher than the cut-off value of RMOD determined on uninfected samples. Based on the serial dilution of the original patient samples, we expect that the method can detect Plasmodium vivax malaria in blood samples with parasite densities as low as \(\sim\)5–10 parasites per microliter, a limit around the pyrogenic threshold of the infection. In addition, by investigating the correlation between the magnitude of the magneto-optical signal, the parasite density and the erythrocytic stage distribution, we estimate the relative hemozoin production rates of the ring and the trophozoite stages of in vivo Plasmodium vivax infections.

旋转晶体磁光检测 (RMOD) 方法已开发用于疟疾的快速定量诊断，并在各种疟疾感染模型上进行系统测试。最近，在巴布亚新几内亚的一个高传播地区进行的扩展现场试验证明了它在检测疟疾感染方面的巨大潜力，特别是间日疟原虫。在目前在泰国低传播地区进行的小规模实地试验中，RMOD 在所有被发现感染间日疟原虫的样本中确认了疟疾通过显微镜，我们的参考方法。此外，该样本集的磁光信号通常比未感染样本上确定的 RMOD 截止值高 1-3 个数量级。基于原始患者样本的连续稀释，我们预计该方法可以检测血液样本中的间日疟原虫疟疾，其寄生虫密度低至\(\sim\)每微升 5-10 个寄生虫，热原阈值附近的限制感染。此外，通过研究磁光信号强度、寄生虫密度和红细胞阶段分布之间的相关性，我们估计了体内间日疟原虫感染的环和滋养体阶段的相对血红素生成率。