Antimalarial drug resistance: at what cost?

The treatment efficacy of Artemisinin Combination Therapies (ACTs), the current frontline treatment against falciparum malaria, is dwindling in many parts of Southeast Asia due to the spread and emergence of antimalarial drug resistance. If this resistance continues to spread or emerge, what will be the global cost?

A recent study published in Malaria Journal compares the projected health and economic consequences if widespread malaria resistance to ACTs spreads or emerges in many more countries. A team lead by the Mahidol Oxford Research Unit (MORU) in Bangkok Thailand developed an economic model to explore a scenario where ACTs failed at a rate of 30 per cent and treatment for severe cases of malaria is reverted to quinine.

“We’re not trying to assess how this antimalarial resistance is likely to spread or how the whole scenario will unfold, but rather consider the consequence of a significant drop in the efficacy of ACTs,”says Dr Yoel Lubell, Health Economist at MORU. “With the confirmation that artemisinin resistance is prevalent in many parts of Southeast Asia, this modelled scenario is not a distant reality, rather a genuine threat that is already evolving here and now. It is only by understanding the scale and potential impact of what might happen in the future that we can begin to prepare for and respond to the complex issues now.”

The model projects that the scenario of widespread antimalarial resistance will result each year in an increase of more than 116,000 deaths, an excess of $32 million in healthcare costs, and an estimated $385 million from productivity losses due to extended patient illness.

This conservative estimate of both the economic and human cost of antimalarial resistance gives an overview of what national governments, health care practitioners, funders, researchers and policy makers may face in the future. The study points to potential avenues to prolong the efficacy of these life-saving medicines, such as extending the dose regimen of ACTs to maintain high patient cure rates, or introducing ACTs with new partner drugs, once existing drugs start to fail more dramatically.

“These figures highlight the potential magnitude of the threat posed by antimalarial resistance to patients, healthcare systems and the economy of affected countries,” says Prof Philippe Guérin, Director of the Worldwide Antimalarial Resistance Network.

“Massive investments have been made to control and decrease successfully the malaria burden. We need to take action now to fight the emergence and spread of malaria drug resistance. This global threat requires that all stakeholders work together to deliver effective measures to prevent this from becoming a terrible reality. We have a limited window of opportunity to respond now,” concludes Prof Guérin.

Download the Malaria Journal paper:

Yoel Lubell, Arjen Dondorp, Philippe J Guérin, Tom Drake, Sylvia Meek, Elizabeth Ashley, Nicholas PJ Day, Nicholas J White and Lisa J White. Artemisinin resistance - modelling the potential human and economic costs. Malaria Journal 2014, 13:452. First available 23 November 2014.  doi:10.1186/1475-2875-13-452