World malaria day 2014
25 April each year marks the World Health Organisation (WHO) World Malaria Day; the theme for the 2013-2015 campaign is ‘Invest in the future. Defeat malaria’. Malaria still carries a high disease burden with more than half a million people dying from malaria every year. One of the biggest weapons we currently use to fight malaria is a compound called artemisinin, which is derived from the sweet wormwood plant. Similar to other previously used anti-malarial treatments, malaria strains resistant to artemisinin are emerging in Western Cambodia and the Cambodia/Thailand border.
NDM spoke to Professor Nick White FRS, whose research has been instrumental in establishing artemisinin combination therapy as first-line treatment for malaria worldwide, about the discovery of artemisinin and what the emerging drug resistance means for the battle against malaria.
Q: How was artemisinin discovered as an effective malaria treatment?
Nick White: Artemisinin is a traditional Chinese medicine that has been known about for at least 2000 years but it was re-investigated in 1970s when Chinese scientists were researching the compounds in the Chinese Materia Matica. It took a long time thereafter to get artemisinin accepted by Western medicine. We did research into the anti-malarial properties of artemisinin and developed the idea that artemisinin in combination with other medications is the most effective treatment for falciparum malaria and the derivative artesunate reduces the mortality the mortality of severe malaria by a third.
NW: Simply put, it is the best anti-malarial there is. Artemisinin combination therapy it the first line treatment option all over the world. It has now replaced the failing previous anti-malaria treatments.
Q: When was artemisinin combination therapy recognised as the best treatment option for malaria?
NW: We developed this treatment in the 1990s; however as with any new medical advance, people were naturally cautious about accepting it. The idea that a traditional Chinese herb would be a really good treatment for malaria was not something that was readily accepted. There were also cost implications which delayed the acceptance of artemisinin as the best treatment option. Malaria is a disease that affects people in the poorest parts of the world, and therefore the drugs would mostly need to be paid for by aid. There can be quite high costs associated with growing and harvesting sweet wormwood, the plant from which artemisinin is produced. However, with large scale plantation, these costs have come down; it now costs less than $1 to treat each case of uncomplicated malaria. Finally, in 2006 the WHO gave a resounding endorsement and the policies changed almost immediately after that. Today artemisinin combination therapy is recognised as the first line treatment option for malaria- a landmark change in the way that malaria is treated.
Q: Are there concerns about artemisinin resistance and if so what does this mean for the future?
NW: There are enormous concerns because resistance has emerged, and furthermore it has emerged in Western Cambodia and the Thai-Cambodian border- the same place where resistance to the other malaria drugs came from. Resistance is now found throughout most of the mainland area of Southeast Asia. The problem is if that spreads to India and Africa, like it has twice before with previous anti-malarial drugs, then that could reverse all the substantial gains that have been made in recent years. The deployment of artemisinin in combination treatments and the deployment of insecticide treated bed nets which protect people from malaria, have together resulted in an approximate one third reduction in the global mortality. Whereas about ten years ago 3,000 people were dying every day, most of them African children, now about 2,000 people are dying every day, which is still far too many, but it means that overall more than 3 million lives have been saved since 2000. If resistance to these drugs spreads all of this could be reversed.