Why are malaria mortality rates different in recent studies?

Online Q&A
February 2012

An article in The Lancet on 3 February 2012 estimated that 1.24 million people died of malaria in 2010 while for the same year, WHO estimated 655 000 people died. 

WHO is grateful for efforts of all partners to improve estimates on malaria and other diseases in public health.

It is well appreciated in the public health community that estimates are very much influenced by the study sites, data, assumptions and methodology used in their studies. In this study, the variation in estimates of deaths over the age of 5 is because different methodologies were used.

WHO stands by their previous estimates that were based on the methodology developed by the UN agency in collaboration with other partners. WHO welcomes the Institute for Health Metrics and Evaluation’s estimates that actually show more similarities than differences.
 Both approaches show that an unacceptably high number of people still die from malaria. The trends in disease are steadily downward by both methods, thanks to investments in scaling up life-saving tools.

To improve disease estimates in the future, it is imperative that resource-constrained countries be supported to develop robust health information systems. This includes accurate diagnosis of causes of deaths; and that all experts working on disease estimates work together more collaboratively to produce accurate and timely data. This information is critical for the decision-making that ensures public health interventions reach the right communities and have the greatest potential of helping more people live longer, healthier lives.