A saliva-based rapid test to quantify the infectious subclinical malaria parasite reservoir

Abstract

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 falciparumgametocyte 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 forP. falciparumgametocyte carriers. The test is capable of identifying submicroscopic carriage in both clinical and nonclinical settings and is compatible with archived saliva samples.

Framework for a Community Health Observing System for the Gulf of Mexico Region: Preparing for Future Disasters

“…In particular, longitudinal cohort studies of the types described here that encompass large, well-characterized, and representative population samples could be expanded as needed to incorporate testing for COVID-19 and other infectious organisms at regular intervals. Such testing might focus on up-to-date technology based on minimally invasive, often self-administered, sampling [e.g., tests of saliva ( 145 , 146 ), nasopharyngeal swabs ( 144 ), dried blood spots ( 147 – 149 ), urine ( 150 , 151 ), and perhaps smartphone apps or other mobile monitoring health devices] to complement existing disease surveillance efforts. Broad scale surveillance for SARS-CoV-2 in wastewater is also possible, as already demonstrated in multiple localities ( 152 – 154 ).…”

The accelerated infectious disease risk in the Anthropocene: more outbreaks and wider global spread

“…However, if efficient and reliable health checks which can identify various diseases and which can be administered relatively timeand cost-efficiently to large numbers of passengers could be implemented, we may be able to significantly restrict the mobility of infected hosts. While such a proposal may sound like "pie in the sky" at the moment, rapid advances in diagnostic techniques, such as translational proteomics, may soon allow us to identify infected hosts using simple breathalyzer, saliva, or urine tests (Athlin et al, 2017;Nakhleh et al, 2017;Tao et al, 2019;Zainabadi et al, 2019). Furthermore, hygienic measures, such as the enforcement of handwashing and the wearing of facemasks in public transport hubs, complete and regular disinfection of important traffic hubs and vehicles (including the air and all surfaces), and much better vector control should become mandatory global standards of public health (e.g., Grout and Speakman, 2019;Nicolaides et al, 2019, reviewed in Huizer et al, 2015, especially in the most central of traffic hubs, such as the world's most connected airports (Guimerà et al, 2005;Bajardi et al, 2011).…”

Rapid range shifts in AfricanAnophelesmosquitoes over the last century

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