Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

An existing malaria rapid diagnostic test (RDT) can be adapted to predict the delayed anaemia that can complicate severe malaria in patients treated with artemisinin-based antimalarial drugs

Researcher checking a child affected with malaria for anaemia

“These findings are relevant to the thousands of western travellers treated each year for malaria and for non-immune adults in low malaria transmission places like Bangladesh, Thailand and Myanmar,” said Dr Charlie Woodrow, one of the study’s lead authors, based at the Mahidol Oxford Tropical Medicine Research Unit (MORU) in Bangkok, Thailand.

“Using a modified rapid test – a dipstick, if you will – physicians can predict who is at high risk of delayed anaemia and anticipate the need for hospital admission and blood transfusion,” explained Dr Woodrow. “Patients identified as being low risk, on the other hand, can be reassured and told to come back only if their symptoms worsen.”

Artesunate, the most commonly used artemisinin for severe malaria, rapidly cures patients with severe malaria but frequently induces anaemic episodes called post-artesunate delayed hemolysis (PADH) for which a simple predictive method has been needed.

The researchers, based in France, Thailand and Bangladesh, found that the underlying event in PADH, the expulsion of artesunate-exposed parasites from their host red blood cells by “pitting”,  leaves behind the parasite component PfHRP2 in the red cell. So using a dipstick to measure the amount of PfHRP2 in the blood just after parasite clearance indicates the number of "deparasitized" red cells – and the risk of life-threatening anaemia.

The finding that PfHRP2 persists in deparasitized red cells also solves a long-standing mystery – why the rapid diagnostic test for falciparum malaria stays positive for so long after treatment.

“Our work hence joins together three separate strands of study – the process of pitting, the persistence of PfHRP2 after treatment and the risk of delayed haemolysis after artesunate,” said Dr Woodrow.

Led by researchers at the National Institute of Blood Transfusion, Paris Descartes University with support from, among others, scientists at the Mahidol Oxford Tropical Medicine Research Unit (MORU) at Mahidol University, Bangkok, Thailand and the Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, the study was funded by the French National Research Agency, the Wellcome Trust (UK) and the Bill and Melinda Gates Foundation.

Study Reference:

Persistence of the Plasmodium falciparum protein HRP2 in the circulation of artesunate-treated malaria patients predicts post-artesunate hemolysis.Ndour PA, Larréché S, Mouri O, Argy N, Gay F, Roussel C, Jauréguiberry S, Perillaud C, Langui D, Biligui S, Chartrel N, Mérens A,  Kendjo E, Ghose A, Hassan MMU, Hossain MA, Kingston HWF, Plewes K, Dondorp AM, Danis M, Houzé S,  Bonnefoy S, Thellier M, Woodrow CJ, Buffet PA,  French Artesunate Working Group. Sci Transl Med. 2017 Jul 5;9(397). pii: eaaf9377. doi: 10.1126/scitranslmed.aaf9377.

Similar stories

The RECOVERY Trial: One year on

OCGHR Research

The Randomised Evaluation of COVid-19 thERapY (RECOVERY) trial was officially launched on 23 March 2020. It is the world's largest COVID-19 drug trial. Thanks to the ground-breaking work of RECOVERY, clinicians treating patients hospitalised with severe COVID-19 now have two treatments that are known to improve survival.

Researchers call for access to Ivermectin for young children

OCGHR Publication Research

Millions of children weighing less than 15kg are currently denied access to Ivermectin treatment due to insufficient safety data being available to support a change to the current label indication. The WorldWide Antimalarial Resistance Network’s new meta-analysis provides evidence that supports removing this barrier and improving treatment equity.

Gender imbalance in visceral leishmaniasis clinical trials

OCGHR Publication Research

Researchers have found that despite an ongoing trend for a decreasing proportion of males being enrolled in antileishmanial therapeutic efficacy trials over time, there are still 1.8 times as many males as females involved in clinical trials. A new systematic review and meta-analysis suggests that existing knowledge on drug efficacy is derived from a study population that is heavily skewed towards adult males. At the same time, substantially less is known about the optimal treatment response in female patients.

New report highlights growing concern of vaccine falsification

MORU OCGHR

The Medicine Quality Research Group has published a new Medical Product Quality Report focussing on increasing issues around substandard and falsified (SF) COVID-19 vaccines. With the implementation of the key innovations of COVID-19 vaccines, there have been growing numbers of reports of SF vaccines in the public domain. Given the vital role they will play in ending the pandemic and protecting the global population but severe issues with equitable access, SF vaccines are highly likely to be a growing problem.

RECOVERY trial closes recruitment to colchicine treatment for patients hospitalised with COVID-19

OCGHR Research

Established to test a range of potential treatments for COVID-19, the RECOVERY trial has included a comparison of colchicine, an anti-inflammatory drug that is commonly used to treat gout, vs. usual care alone. There has been no convincing evidence of the effect of colchicine on clinical outcomes in patients admitted to hospital with COVID-19, and recruitment to the colchicine arm of the RECOVERY trial has now closed. Recruitment to all other treatment arms – aspirin, baricitinib, Regeneron’s antibody cocktail, and dimethyl fumarate – continues as planned.

World’s largest clinical trial for COVID-19 treatments expands internationally

EOCRU OCGHR OUCRU OUCRU-Nepal Research

The Randomised Evaluation of COVID-19 Therapy (RECOVERY) Trial, the world’s largest clinical trial for COVID-19 treatments, has now expanded internationally with Indonesia and Nepal among the first countries to join. The first patients have been recruited to RECOVERY International.