Episode #3 | 15 October 2021
Malaria parasites mutate and have ability to evade rapid diagnostic tests
Results from a large study in Ethiopia showed that P. falciparum malaria parasites have mutated and have the worrisome ability to avoid being detected by the widely used rapid diagnostics tests, RDTs.
Controlling malaria requires an effective ‘test and treat’ strategy. Traditionally, the most utilized test in Africa is the rapid diagnostic test (RDT), which detects histidine-rich protein 2, a protein made by P. falciparum malaria parasites. Although histidine-rich protein is abundant in human blood during malaria infection and an excellent target for testing - it’s been reported since 2010 that mutations in the parasite have resulted in the deletion of the gene encoding this protein, enabling those parasites to avoid detection by RDTs.In a large study of nearly 13,000 participants conducted in Ethiopia results from RDTs were cross-referenced with those from more reliable methods of diagnosis. Researchers found that RDTs would miss an estimated 9.7% of cases owing to the deletion of this protein, significantly higher than the WHO’s 5% threshold for test regime change.