WHO approves new testing tool to combat recurring malaria

A groundbreaking testing tool that could help reduce recurring cases of one of the world's most persistent forms of malaria has received approval from the World Health Organization (WHO).

The new diagnostic tool tests for glucose-6-phosphate dehydrogenase (G6PD) deficiency, a genetic condition affecting over 500 million people worldwide. This enzyme deficiency can make certain malaria treatments dangerous for patients, as these medications can destroy their red blood cells.

"This prequalification can help strengthen the global malaria response by reducing P. vivax reinfections and limiting transmission," said Dr. Daniel Ngamije Madandi, WHO's Director of Global Malaria Programme, in a statement.

The impact could be significant, as Plasmodium vivax (P. vivax) malaria affected approximately 9.2 million people in 2023. The parasite is present in all WHO regions except Europe, making it a global health concern.

The WHO explains that a G6PD deficiency is a genetic condition that affects more than 500 million people.

"While most people are unaware of their G6PD deficiency and go through life without suffering ill effects, certain drugs administered to prevent malaria relapse caused by P. vivax can result in acute haemolysis (destruction of red blood cells). Without accessible and reliable G6PD testing, it has been challenging to safely provide anti-relapse treatments, limiting the widespread use of this effective therapy," explains the WHO.

The new tool will now be used to analyse results of patients with G6PD activity levels above and below the normal levels and in turn provide critical information to clinicians to decide which of P. vivax anti-relapse treatment regimens is most appropriate. The testing device, SD Biosensor, Inc., is designed for use in both laboratory and field settings. It works with a hand-held analyser that delivers results within minutes, making it particularly valuable in resource-limited areas.

"The prequalification of this G6PD enzyme test for patients with P. vivax malaria can help countries in enhancing access to much-needed quality-assured tests, enabling safe and effective treatment and prevention of this type of relapsing malaria," said Dr Yukiko Nakatani, WHO Assistant Director-General for Access to Medicines and Health Products in a statement released on Wednesday evening.

The approval comes after WHO's recent update to its malaria guidelines in late 2024, which included recommendations for tafenoquine-based treatments. When combined with chloroquine, these treatments offer new hope for preventing malaria relapses caused by P. vivax.

However, the WHO notes that more testing options are needed. Dr. Nakatani called for manufacturers to submit additional products for prequalification to expand the range of available diagnostic tools.

"Currently, no other prequalification applications are received for this type of test. We encourage the submission of additional products to expand the range of effective diagnostic tools available to countries in need," she added.

The development is particularly relevant for countries like Kenya, where malaria remains a major public health challenge, with climate change expanding the disease's reach into previously unaffected regions.

Approximately 70% of the population at risk of infection, with the disease accounting for approximately 15% of all outpatient consultations in Kenyan health facilities. Children under 5 years and pregnant women remain the most vulnerable groups.

The disease contributes to about 10% of deaths in children under five years. Infection patterns vary significantly across the country's different geographical regions. The Lake Victoria region and coastal areas experience year-round malaria transmission, with the highest burden in counties like Siaya, Kisumu, Homa Bay, Migori, Kilifi, and Kwale. These areas have climate conditions that favor mosquito breeding throughout the year.

Areas like parts of Nyanza, Western, and Central regions, particularly those at elevations between 1,300-1,700 meters, experience seasonal malaria transmission. These regions are seeing an increase in cases due to climate change affecting traditional weather patterns.

Nairobi and the central highlands historically have had minimal malaria risk due to their higher altitude and cooler temperatures. However, climate change is gradually altering this pattern.

Control and treatment of malaria in the country remains a challenge because there's growing concern about emerging resistance to artemisinin-based combination therapies (ACTs).

[email protected]