New malaria study by Oxford Uni to inform WHO guidelines
New research will help treating children with a specific type of the disease.
Last updated 4th Oct 2024
Researchers from the Centre for Tropical Medicine and Global Health at Nuffield Department of Medicine at Oxford University have contributed to a new study which will help inform World Health Organization guidelines for treating children with malaria.
They found that giving children higher doses of primaquine substantially reduced recurrences of a specific type of malaria.
The form of the disease is known as Plasmodium vivax malaria.
The new study analysed the data of 3,514 children from 27 studies and 15 countries to determine the efficacy and safety of different primaquine dose strategies in children.
It showed a higher total dose of primaquine as part of the radical cure of P. vivax reduced the risk of recurrences.
In children with 30% or higher glucose-6-phosphate dehydrogenase activity- a genetic disorder that affects red blood cells- primaquine doses up to 0.5 mg/kg/day (for up to 14 days) were safe and well tolerated.
Plasmodium vivax is endemic in 49 countries and is becoming the predominant malaria species outside Africa.
Between five and 14 million cases of P. vivax malaria occur each year. P. vivax and P. ovale are the only major malaria parasites infecting humans that lie dormant for weeks to months after the initial infection, before activating to cause recurrent malaria episodes (relapses).
Primaquine is the only widely available treatment to prevent relapsing malaria and treatment is currently administered as tablets for all groups.
The lack of paediatric formulation, and the safety concerns with the use of higher doses and in G6PD deficient people, have been some of the practical challenges for the wider implementation of primaquine.
First author Associate Professor Rob Commons, from the Infectious Diseases Data Observatory, said: "As with many antimalarials, primaquine has been under-dosed in children for many years.
"This study demonstrates the importance of a higher total primaquine dose to prevent recurrent malaria and will be important as new child-appropriate primaquine medication becomes available in the near future.’"
Professor Karen Barnes from the same organisation said, "This manuscript demonstrates the potential of rapidly generating new knowledge to support the deployment of paediatric primaquine by pooling all available data, and bringing together those who generated these data in a WWARN Study Group.
"This approach avoids the considerable costs and delay of conducting new studies in young children, who are generally underrepresented in most P. vivax and ovale studies.’