Burnet Institute Head, Biomedical Research, Professor James Beeson
On World Malaria Day, Burnet Institute’s Head, Biomedical Research, Professor James Beeson, has contributed to the Oxford University Press Blog on the continuing quest for a malaria vaccine. The following is an excerpt of Professor Beeson’s commentary.
The 2016 World Malaria Report estimates that there were approximately 215 million cases of malaria and 438,000 deaths in 2015. The majority of deaths occur in sub-Saharan Africa, and among young children, and malaria remains endemic in around 100 countries with over 3 billion people at risk. Over the past 15 years there have been major gains in reducing the global burden of malaria; however, it continues to be a major cause of mortality and morbidity globally.
April 25 marks World Malaria Day, highlighting key issues in the fight against this major disease. Plasmodium falciparum causes the bulk of malaria, with P. vivax being a second major cause. World Malaria Day 2016 highlights the need for innovation to develop effective vaccines, new drugs, and better diagnostics to ensure continued success towards malaria elimination.
An effective vaccine has long been a goal of the global community, and the tremendous benefits of low cost, safe, and highly effective vaccines have been demonstrated with other infectious pathogens. The WHO Malaria Technology Roadmap sets out the goals for malaria vaccine development with the aim of achieving a licensed vaccine with more than 75 percent efficacy by 2030, and vaccines that reduce malaria transmission to facilitate malaria elimination.
However, achieving highly efficacious vaccines has proved exceptionally challenging. The most advanced vaccine, known as RTS,S, and the only malaria vaccine to have progressed through formal phase III trials, showed significant, but modest, efficacy of 26-3 percent among infants and young children even with a booster dose.
Over recent years, major progress has been made in understanding … merozoites, (the form of the malaria parasite that invades red blood cells), as well as the nature and targets of immune responses that block infection. This has enabled the identification of several promising vaccine candidates.
Effective immunity appears to involve multiple different immune mechanisms, including the ability of antibodies produced by the immune system to directly block merozoite function, recruit complement proteins from the blood to kill or inactivate merozoites, and interact with leukocytes to clear infection.
The persisting challenges faced in malaria control and elimination, including escalating drug resistance, insecticide resistance, and insufficient funding, further strengthen the importance of the long term goal of developing highly effective malaria vaccines to protect humanity from one its greatest foes.
To read Professor Beeson’s commentary in full, go to www.blog.oup.com.