Next-generation rapid tests for malaria
What is this project?
This project is focused on development of improved rapid diagnostic tests (RDTs) for Plasmodium falciparum malaria parasites, and the evidence generation to support their implementation. These tests are sensitive enough to detect malaria in particularly difficult-to-diagnose groups of people, such as pregnant women, and can also support elimination efforts by detecting asymptomatic infections with low parasite densities.
Why are we working on it?
The sensitivity of conventional malaria RDTs is roughly equivalent to that of light microscopy, and is not good enough to detect infections with low parasite densities that can still enable transmission of the infection, which can often be asymptomatic. Point-of-care tests with enhanced sensitivity that are still easy to use in very minimally resourced health facilities are also needed for “active case finding” – the proactive screening of communities to identify infections in people with or without symptoms, vital for disease elimination.
Pregnant women with malaria are a key population for these tests. Low parasite densities coupled with their tendency to hide out in the placenta means that infections during pregnancy are typically missed by light microscopy or conventional RDTs. These undetected parasites can cause damage ranging from maternal anaemia to low birth weight – an important contributor to infant mortality.
What does it involve?
Several promising, innovative technologies have been developed with our support, and we are now assessing their diagnostic performance for the detection of low-density or placenta-sequestered malaria infections occurring during pregnancy.
One is a rapid test to detect Plasmodium falciparum parasites that is 10 times more sensitive than current RDTs when tested in the laboratory, which we are currently trialing in various countries. Use of this highly sensitive (hs)RDT in active case finding is also being evaluated, as a first step to gather national and then global evidence to establish this as the optimal RDT to support elimination efforts.
Alongside these efforts focused on pregnancy, we are also evaluating improved RDTs that can detect specific antigen combinations (pLDH/HRP2) for P. falciparum alone as well as both P. falciparum and P. vivax together. These assessments will generate evidence that could support WHO pre-qualification.
What do we expect to achieve?
These studies will provide critical evidence about the performance of new tests and their capacity to improve detection – and therefore treatment – of malaria in pregnant women. This information could pave the way to policies recommending the use of such tools for malaria detection in pregnant women.
Active case finding work will serve as a path-finder for engagement with national and regional malaria control programmes, allowing us to build a global evidence base to support evaluation of the tools needed for effective disease elimination.
What is the timescale?
These activities are expected to run for 7 years, between 2014 and 2021.
Partners and funding
The P. falciparum hsRDT was developed in partnership with Standard Diagnostics, supported by the Bill & Melinda Gates Foundation and PATH. The pLDH/HRP2 RDTs were developed in partnership with Abbott, the Bill & Melinda Gates Foundation and PATH.
Evaluation activities are supported by the Australian government, UK aid from the British people, as well as the Bill & Melinda Gates Foundation.
For more information please contact us.