World Malaria Day is an annual event observed on April 25 to promote awareness of the global effort to control and eventually eradicate malaria. According to the World Malaria Report, malaria caused an estimated 241 million clinical episodes and 627,000 deaths in 2020 and it continues to be a leading cause of death and disease in many developing countries. Direct costs of the disease have been estimated at in excess of €10 billion per year with the indirect costs, in terms of lost economic growth, being many times more than this.
The first-ever vaccine for malaria was approved by the WHO for broad use in children in 2021, however, it requires four doses and the results of a phase-3 trial reduced the number of cases among young children by 50% and among infants by 25%. Further vaccines are currently undergoing clinical trials and early results from phase-2 trials indicate improved efficacy rates of over 75%. In addition, cancer therapeutic, repurposed to treat malaria, has been shown in ongoing clinical trials to be nearly 100% effective in clearing all malaria parasites from a patient in three days. The big challenge for humanity is to ensure that everyone can get access to these new vaccines and therapeutics.
Malaria is caused by a single-cell parasite, Plasmodium, which is carried by mosquitoes. Soft X-ray Tomography was an essential method used to study the nucleation and growth of the malaria pigment hemozoin in Plasmodium parasites. Hemozoin formation is necessary for malaria parasite survival in a human host.
Using a combination of soft X-ray tomography with X-ray fluorescence microscopy, an international team of researchers investigated the link between haemoglobin digestion and the rate of hemozoin formation. This synergy of X-ray methods enabled researchers also to observe a quinoline-type drug interfering with heme detoxification inside the parasite by capping hemozoin crystals and preventing their growth. These findings help identify and understand promising targets that may play a key role in developing new antimalarial medicine.
Dr. Sergey Kapishnikov et.al