Malaria kills more people worldwide than once thought, study says

In an alarming statistical turn, the number of malaria deaths every year may be vastly underestimated, according to new research re-examining mortality rates from 1980 to 2010.

According to a study published in the journal the Lancet, in 2010 there were 1.24 million deaths from malaria worldwide -- nearly twice the World Health Organization estimate of 655,000.

And while it’s true that malaria deaths have dropped by about 32% since their peak of 1.82 million in 2004, in many regions adults now account for a large slice of the mortality figures.

That’s surprising, because many researchers thought most malaria deaths occurred in children in the 0-to-5-years age range, perhaps because many adults survive a malaria infection as children and should be less vulnerable to one later in life.

But it turns out they may have overlooked many malaria deaths in older children and adults. For example, in 2010, the WHO estimated that 91,000 people age 5 and up died from malaria; but according to the new figures, there were 524,000 deaths in that age group.

Not everyone has accepted the new numbers. The WHO says it stands by its figures, according to this Reuters story.

And according to an editorial accompanying the study, “the authors will need to make their data and assumptions fully available to others who will surely wish to reproduce their calculations.”

But, the editorial concludes, “malaria might be a far more important cause of childhood mortality than previously thought. If correct, this finding has substantial implications for child survival programmes. It also seems clear that malaria is a greater long-term threat to adult health than we previously imagined.”

The research was funded by the Bill and Melinda Gates Foundation, which has invested millions in malaria-eradication efforts worldwide.

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