Development a point-of-care lateral flow test for artemisinin-resistant malaria

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Artemisinin-based combination therapy is currently recommended by WHO for treatment ofuncomplicated falciparum malaria. However, artemisinin resistance is threatening the effectivenessof these antimalarials and has spread rapidly in South-East Asia [1]. Should artemisinin-resistantmalaria (ARM) spread from this region to Africa, as did resistance to older antimalarials, much of theprogress made in reducing the prevalence of malaria could be reversed.While the mechanism of ARM is still only partially understood, multiple single-nucleotidepolymorphisms in the propeller domain of a kelch gene, located on chromosome 13, have beenshown to be associated with artemisinin resistance [2]. Two single nucleotide polymorphisms,C580Y and R539T, are the most prevalent SNPs associated with ARM and account for 85% in SouthEast Asia, with some areas having a prevalence as high as 90% [3].Since the discovery of the molecular markers for ARM, nucleic-acid based tests such as polymerasechain reaction (PCR) have been used to test for ARM. However PCR-based techniques requirecomplex apparatus, trained personnel and external power, and therefore are not readily available inresource-poor settings. This method is useful for epidemiological studies but does not allow forresults to be used in case-management as the molecular testing is conducted long after thecollection of blood from the patient.To overcome these challenges, other techniques such as loop-mediated isothermal amplification(LAMP)-based methods have been developed. LAMP has many advantages due to its low cost andsimplicity, and is increasingly used as point-of-care tests by clinicians for other infectious diseases. Ithas been shown to be user-friendly and cost-effective [4]. MicrofluidicsTo date there is no point-of-care (POC) test available to detect ARM. A POC test for AMR in malariaendemic areas could help to inform clinicians about appropriate case management for patients.Currently alternative drug regimens such as the use of partner drugs and longer treatments arebeing evaluated for ARM, however this can lead to drug toxicity and multidrug-resistant malaria [5].POC tests for ARM would therefore enable clinicians to provide appropriate treatment and limit theoveruse of existing antimalarials. POC tests would also provide real time data for epidemiologicalstudies.ObjectivesThe main objective of this project is to develop a new low cost test that will combine microfluidicsand finger prick sampling to enable for the first time the testing of ARM at the POC. The test woulduse LAMP to test for the most common SNPs conferring ARM and would use lateral flow andmicrofluidic technology. The test should have sensitivity and specificity as close as possible to PCR,while being suitable for use in low-resource environments, with the minimal requirements foradditional equipment.