
Saliva-based Rapid Diagnostic Tests
Despite widespread malaria control efforts, residual malaria transmission continues to be observed, calling in to question whether the global malaria elimination goals can actually be achieved. A large proportion of this residual malaria parasite transmission is due to low numbers of parasites that cannot be detected by available blood-based rapid diagnostic tests (RDTs) or microscopy. This subclinical or “carrier” population is a major obstacle to achieving the global malaria elimination goals, as they comprise the parasite reservoir that leads to infection of mosquitoes and persistent local transmission. However, no point-of-need (PON) RDTs for malaria parasite detection have made it to the market, much less one that is highly mobile and can perform non-invasive sampling of saliva outside a clinic, for example in schools or homes. We discovered a conserved, strain-transcending Plasmodium parasite protein marker (PSSP17) present in the saliva of children with a subclinical malaria parasite infection (both asexual blood stages and sexual stage gametocytes). We have developed and validated a prototype PON RDT to fulfill this unmet need. We have recently expanded our later flow platform to COVID-19 and anemia. See here for more details: https://www.nibib.nih.gov/ntac-challenge-winners