"This week we publish surprising and, on the face of it, disturbing findings. According to Christopher Murray and colleagues at the Institute for Health Metrics and Evaluation (IHME) at the University of Washington in Seattle, there were 1·24 million deaths (95% uncertainty interval 0·93—1·69 million) from malaria worldwide in 2010—around twice the figure of 655 000 estimated by WHO for the same year. How should the malaria community interpret this finding? Before we answer that question, we need to look beneath the surface of this striking overall mortality figure.

"First, annual malaria mortality peaked in 2004 at 1·82 million. Since then, there has been a 32% reduction in malaria deaths, driven mainly by “accelerated decreases” in sub-Saharan Africa. Second, although there has also been a substantial decrease in the number of deaths outside sub-Saharan Africa, adults now make up the major burden in these regions. "In Asia and the Americas, the median proportion of deaths in those older than 15 years was 76% and 69%, respectively. Overall, the IHME data show that malaria deaths in 2010 in those aged 5 years and older were much higher than previously thought—524 000 deaths compared with 91 000 as estimated by WHO. Third, malaria accounts for many more child deaths in sub-Saharan Africa than previously estimated—24% of total child deaths, compared with the 16% previously calculated for 2008.

"The reliability of these findings will certainly be the subject of much debate, as were the similarly higher estimates for India (by different methods), reported in 2010. Murray and colleagues used inputs from vital registration systems, published and unpublished verbal autopsy reports, and estimates of malaria transmission intensity to construct an array of models, which were then assessed for predictive validity. The authors will need to make their data and assumptions fully available to others who will surely wish to reproduce their calculations."

The Lancet, Volume 379, Issue 9814, Page 385, 4 February 2012
doi:10.1016/S0140-6736(12)60169-X