A saliva-based rapid test to quantify the infectious subclinical malaria parasite reservoir
A large proportion of ongoing malaria parasite transmission is attributed to low-density subclinical infections not readily detected by available rapid diagnostic tests (RDTs) or microscopy. Plasmodium falciparum gametocyte carriage is subclinical, but gametocytemic individuals comprise the parasite reservoir that leads to infection of mosquitoes and local transmission. Effective detection and quantification of these carriers can help advance malaria elimination strategies. However, no point-of-need (PON) RDTs for gametocyte detection exist, much less one that can perform noninvasive sampling of saliva outside a clinical setting. Here, we report on the discovery of 35 parasite markers from which we selected a single candidate for use in a PON RDT. We performed a cross-sectional, multi-omics study of saliva from 364 children with subclinical infection in Cameroon and Zambia and produced a prototype saliva-based PON lateral flow immunoassay test for P. falciparum gametocyte carriers. The test is capable of identifying submicroscopic carriage in both clinical and nonclinical settings and is compatible with archived saliva samples.
Copyright © 2021 American Association for the Advancement of Science. This article first appeared in Science Translational Medicine, 2 Jan 2019• Vol 11, Issue 473.
Tao D, McGill B, Hamerly T, Kobayashi T, Khare P, Dziedzic A, Leski T, Holtz A, Shull B, Jedlicka AE, Walzer A, Slowey PD, Slowey CC, Nsango SE, Stenger D, Chaponda M, Mulenga M, Jacobsen KH, Sullivan DJ, Ryan SJ, Ansumana R, Moss WJ, Morlais I, Dinglasan RR. A saliva-based rapid test to quantify the infectious subclinical malaria parasite reservoir. Science Translational Medicine. 2019 Jan 2; 11(473): eaan4479. https://doi.org/10.1126/scitranslmed.aan4479