The malaria mosquito forming the eye-sockets of a skull, representing death from malaria. Colour lithograph after A. Games, 1941.
Malaria remains one of the world’s biggest disease burdens, but where to invest the increasingly limited funds available for intervention? The way to know is through research. On World Malaria Day, Marta Tufet guides us through some of the trials looking to answer the difficult questions.
Once again we join the rest of the world in marking World Malaria Day. This year we’re being urged to “Invest in the Future: Defeat Malaria”, and indeed we must look at the future. But first let’s briefly take stock of past achievements.
Over the past decade, investment in malaria has led to unprecedented momentum with malaria deaths falling by over 20 per cent worldwide with 43 countries reducing malaria cases of death by 50 per cent or more. This progress is remarkable, but what will happen if support starts to decrease? The appetite for new initiatives brought on by the turn of the century has waned, and the 2008 economic crisis continues to threaten international budgets. Will we be able to sustain past achievements with reduced financial support? Probably not. As Mark Dybul, Director of the Global Fund to Fight AIDS, Tuberculosis and Malaria, rightly noted “infectious diseases don’t pay much attention to budget cycles”. Indeed, to understand the risk we are currently facing we need only remind ourselves of the WHO’s Global Malaria Eradication programme of 1955, of which the achievements were quickly reversed with a resurgence in the disease once the funding waned.
When it comes to malaria there is the hope that an effective vaccine would provide the answer. But optimism for a vaccine for this complex multiple-stage parasite is falling after a string of disappointing results that culminated last year when the most promising potential malaria vaccine, RTS,S, failed to show substantial protection in the key age group during a large Phase III clinical trial. Treatment is available for the disease, but as researchers from the Wellcome Trust’s Major Overseas Programmes are reporting, the parasite is quickly developing resistance to our frontline drugs, and unfortunately new antimalarials have not being developed at the same speed as have new antiretroviral drugs for HIV. An array of potential effective prevention and treatment intervention strategies for malaria do exist, but where resources are scarce, how are stakeholders to make informed decision on where to invest? The answer will come from research.
Randomised controlled trials are acknowledged to provide the most robust evidence of the utility of interventions to improve human and animal health, so to give you a flavour for the type of research that can help support some important policy decisions, I’d like to give you some examples of intervention trials which are currently supported by the Global Health Trials Initiative – a joint funding partnership of the Department for International Development, the Medical Research Council and the Wellcome Trust.
In Indonesia, Feiko Ter Kuile is looking at whether more frequent screening of pregnant women and subsequent treatment than currently recommended by national policy would be a more optimal and cost-effective strategy to reduce malaria infection at birth. In Uganda, Sarah Staedke is evaluating whether curative doses of antimalarial treatment at predefined intervals – regardless of infectious status – to schoolchildren could reduce malaria transmission at a population level. In the Gambia, Umberto D’Alessandro is researching whether a reduced dose of primaquine could still be effective against malaria. This drug is very effective against malaria and its use is recommended by WHO guidelines but in practice its use has been limited as at its current recommended dose it is toxic to people with G6PD deficiency, an inherited disorder of their red-blood cell metabolism that is particularly common in malaria endemic countries. In Senegal, to avoid a resurgence of malaria following the dramatic decreases following the distribution of insecticide treated bed nets, Badara Cisse is evaluating to what extent intensified malaria control, employing indoor residual spraying with insecticide and chemotherapy, targeted to villages with persistent transmission can virtually eliminate malaria.
This is just a glimpse of the types of questions that need to be answered to determine and improve the delivery and scale-up of key cost-effective interventions that together will reduce the burden of this deadly killer.
Marta Tufet
Marta Tufet is International Activities Adviser at the Wellcome Trust.
Image credit: Wellcome Library, London
Filed under: Health, Infectious Disease, International Tagged: Malaria, World Malaria Day
