Clinical accuracy of malaria loop-mediated isothermal amplification assay as a stand-alone screening tool at a non-endemic Northern California regional health system

Malaria is critical to rule out in febrile returned travelers. We evaluated the performance of the Alethia Malaria loop-mediated isothermal amplification (LAMP) assay for rapid one-time malaria screening using nucleic acid amplification testing. Retrospective analysis of 51 archival blood specimens collected from 32 patients with malaria and 25 uninfected controls showed Malaria LAMP assay to have sensitivity of 100% (95% CI 93.0-100) and specificity of 100% (95% CI 86.7-100) using blood smear microscopy as the reference standard. Prospective evaluation of Malaria LAMP as a single screening test in 205 patients identified 4 (1.95%) positives which were all confirmed as Plasmodium falciparum by PCR, with parasitemia quantified as <0.1% (n = 2), 1.0% (n = 1), and 4.6% (n = 1). Alternative diagnoses were found in 129 of 201 (64.2%) of LAMP negative patients, and no patient was subsequently diagnosed with malaria. The Malaria LAMP offers a sensitive and rapid stand-alone screening alternative in non-endemic settings.(c) 2022 Elsevier Inc. All rights reserved.