Malaria screening in resource-poor settings using a simple, power-free, cell phone-friendly device

描述(申请人提供)：疟疾是一种威胁生命的疾病，由四种疟原虫之一引起，这些寄生虫通过受感染蚊子的叮咬传播给人。仅在2012年，疟疾就造成超过62.5万人死亡，其中大部分是非洲儿童。由于疟疾在撒哈拉以南地区的高儿童死亡率和流行率，尼日利亚于2000年启动了一项新的方案--减少疟疾(RBM)，旨在通过采用推定治疗(PT)来减轻疟疾的负担，在许多情况下，仅以发烧为疟疾感染的单一征兆。这种方法是必要的，因为实验室支持有限，导致等待实验室诊断的时间很长，从而增加了与延迟的抗疟疾治疗相关的风险，这往往是当地卫生服务提供者唯一可用的选择。尽管研究表明，自采用PT方法的地区开始实施注重结果的管理方案以来，疟疾负担显著减少，但继续这种做法已经导致对疟疾的过度诊断、对其他疾病的低估、药物浪费增加、抗疟疾药物不良反应增加、寄生虫耐药性增加，并给当地卫生系统带来不必要的财政负担。我们建议开发一种基于磁悬浮原理的无抗体诊断筛查设备，允许将感染的红细胞与未感染的红细胞分离。我们的筛选设备重量轻、一次性、制造成本低，在室温下保质期不确定。该原型系统需要不到一滴指刺血液(&lt；1μ�L)和小体积的含有顺磁性离子的红细胞友好缓冲液。仅通过使用固定在包含血液的玻璃/塑料毛细管周围的塑料结构中的一组永久磁铁，就可以在几分钟内获得二元诊断结果。结果被记录下来，并使用标准的拍照手机进行存储。不需要额外的成像设备、染色试剂或消耗品。

DESCRIPTION (provided by applicant): Malaria is a life-threatening disease caused by one the four species of Plasmodium parasites that are transmitted to people through the bites of infected mosquitoes. In 2012 alone, malaria caused over 625 000 deaths, mostly among African children. Due to its high child mortality and prevalence in Sub-Saharan regions, in 2000 a new program was launched in Nigeria, the Roll Back Malaria (RBM), aiming at reducing the burden of malaria by using presumptive treatment (PT) based, in many cases, only on fever as single sign of malaria infection. This approach, necessary due to limited laboratory support leading to long waiting times for laboratory diagnostic and consequently increased risks associated with delayed anti-malaria treatments, is often the only available option for local health service providers. Although studies have shown a significant decrease in malaria burden since the beginning of the RBM program in areas where the PT approach is employed, continuation of this practice already led to over-diagnosis of the malaria, under-diagnosis of other illness, increased drug wastage, increase adverse anti-malaria drug reactions, increased parasite-drug- resistance, and unnecessary financial burden to local health systems. We propose to develop an antibody- free diagnostic screening device that is based on the principles of magnetic levitation, allowing for separation of infected red blood cells from un-infected red blood cells. Our screening device will be light-weight, disposable, and cheap to manufacture with an indefinite shelf life at room temperature. The prototype system requires less than a drop of fingerprick blood (<1 μ�L) and a small volume of RBC-friendly buffer containing paramagnetic ions. Binary diagnostic results is obtained within a few minutes solely by using a set of permanent magnets immobilized in a plastic structure surrounding a glass/plastic capillary containing the blood. Results are recorded and stored using a standard camera phone. No additional imaging equipment, staining reagents, or consumables are required.