ASTMH 2018: Session 73 “Next Generation Rapid Diagnostic Tests for Malaria: Prospects and Considerations”

MESA Correspondents bring you cutting-edge coverage from the 67th ASTMH Annual Meeting

Session 73: “Next Generation Rapid Diagnostic Tests for Malaria: Prospects and Considerations”

Malaria rapid diagnostic tests (RDT) have transformed our ability to diagnose malaria at the point of care. Since their introduction in the mid-1990s, the focus has been on ensuring the quality of these products and that they demonstrate satisfactory sensitivity and specificity at a certain level, usually taken as 100 parasites per microliter of blood, a threshold considered to be clinically relevant for the diagnosis of acute P. falciparum malaria. New malaria RDTs with improved sensitivity are entering the market. Specifically, in 2017, an ultrasensitive RDT for P.falciparum was launched with a greater than tenfold improvement in analytical sensitivity for the commonly used HRP2 antigen.

In 2018, the WHO Global Malaria Program held a technical consultation to review the possible role of ultrasensitive tests in elimination.

In this symposium, a framework for understanding the value proposition for these new diagnostic tools was presented in the context of data generated with respect to elimination and malaria in pregnancy.

Xavier Ding presented on the performance of selected rapid diagnostic tests for the detection of asymptomatic malaria infections. He gave a comprehensive review of the performance of the best-in-class RDTs for P.falciparum malaria, including the recently launched ultrasensitive test.  Using a FIND-managed specimen bank Xavier confirmed the incremental improvement in diagnostic sensitivity of the ultrasensitive RDT for detection of asymptomatic cases, without reaching the sensitivity of molecular gene amplification tests.

Ana Maria Vazquez presented on the performance of the Alere™ Malaria Ag P.f ultrasensitive test (Abbott) for malaria in pregnancy. Through two studies in pregnant women, in collaboration with FIND (Geneva, Switzerland), she demonstrated improved sensitivity for diagnosis of malaria during pregnancy, and particularly for placental malaria.

Hannah Slater presented data on the sensitivity of the new RDT in different transmission settings, and then outlined a framework for combining new data on these tests with mathematical and statistical modelling approaches to estimate the utility of this test in different use case scenarios.

Scott Miller presented an overview of the evolving needs for new diagnostic tools for malaria control and elimination that will be required to support better case management and malaria elimination for both P.falciparum and P.vivax. Products currently entering the market are exciting improvements for the malaria community but further transformational improvements may require new technology beyond the lateral flow RDT platforms.

Co-Chairs: Gonzalo Domingo (PATH, Seattle, USA) and Xavier Ding (FIND, Geneva, Switzerland)

This report was written by Gonzalo Domingo with editorial support from Professor Graham Brown.