Malaria control vs elimination vs eradication
On 24 September The Lancet reported the presentation of this year's Lasker-DeBakey Clinical Medical Research Award to Tu Youyou, a Chinese pharmacologist, for discovering the antimalarial drug artemisinin in the 1970s. Breakthroughs in malaria research such as hers, together with increased funding and control efforts during the past decade, have led to impressive reductions in mortality in many developing countries.
These successes were recently acknowledged by the Roll Back Malaria (RBM) Partnership, a coalition of more than 500 public and private sector partners, tasked with facilitating and coordinating implementation of malaria control. Their new report, A Decade of Partnership and Results, noted that, in the past decade 1•1 million deaths in children with malaria have been averted in sub-Saharan Africa. During 2000—09, the overall number of malaria cases was reduced by 23% in 105 countries and the number of deaths by 38%, with 43 countries (11 of them in Africa) cutting malaria cases or deaths by 50% or more. The report also states that in the past 4 years, Morocco, Turkmenistan, and the United Arab Emirates have been certified by WHO as having eliminated malaria. All these successes have been achieved in part by large increases in funding for malaria, from about US$100 million in 2003 to $1•5 billion in 2010. Energised by these gains, RBM has set new targets: to achieve near zero deaths by 2015, and further elimination of the disease in an additional eight to ten countries.
But celebration of success needs to be tempered with caution. The RBM report warns that some countries have not yet begun to scale up malaria interventions, while others are struggling to sustain their success. Resistance to drugs and insecticides are further threatening gains. Moreover, given that donor funding for malaria has actually fallen in the past 2 years, the anxiety is that donors will be tempted to stop funding successful countries and divert funds elsewhere to high-burden nations. One only has to look back at the Global Malaria Eradication Programme, launched by WHO in 1955, whose achievements were rapidly lost when support waned, which led to a resurgence in malarial disease. An analysis unveiled in New York this week estimated for the first time the ongoing public health and economic benefits of sustaining malaria control activities in countries that have brought the malaria burden down. In four countries alone—Ethiopia, Rwanda, Zambia, and Tanzania (Zanzibar specifically)—sustained control could avert about 151 million malaria cases during the next 5 years, similar in impact to child vaccination campaigns.
One contentious issue is measurement of disease burden, which for malaria is further challenged by its complex epidemiology. Figures from the annual WHO malaria report continue to be disputed by experts. Last year, an article by Dhingra and colleagues in The Lancet showed that there are more than 13 times more malaria deaths (205 000) in India than currently estimated by WHO (15 000). The study points to the fact that the scale of the disease burden could be greatly underestimated elsewhere in the world. Such discrepancies in measurement will affect disease-control strategies and have serious consequences for current debates about funding. There is an urgent need for improved estimates of malaria incidence and mortality. A potentially useful initiative is the creation of a Malaria Policy Advisory Committee, proposed by the WHO Global Malaria Programme. But this committee will only work if it is truly independent of WHO. Such a body could serve as a crucial bridge between WHO and the scientific community.
But what of the next 10 years in malaria control? As noted in The Lancet's Malaria Elimination Series, daunting challenges lie ahead. A key message was that elimination is all about managing expectations and defining what in fact is a good end game—effective control. Following the call by Melinda and Bill Gates in October, 2007, to eradicate malaria, next month their Foundation will host the 2011 Malaria Forum—Optimism and Urgency—in Seattle. It promises to be a high-level event, with leading scientists and agency heads in full attendance. The meeting aims to draw attention to malaria control and elimination; promote continued momentum to achieve malaria control targets by 2015 and the longer-term goal of eradication; and define the challenges ahead and discuss how to address them.
As Maria Freire, president of the Lasker Foundation, notes, three attributes were key to Tu Youyou's malaria work: creativity, innovation, and determination. These qualities will also be crucial for the malaria community to make progress during the next decade. Business as usual will not do.
Full article available online