Malaria: Kills half a million more people each year than previously thought

A new international study involving researchers from The University of Queensland (UQ) has found more than 1.2 million people died from malaria worldwide in 2010 – twice the number found in the most recent comprehensive study of the disease.

Head of UQ's School of Population Health and one of the study's co-authors, Dr Alan Lopez, said malaria is killing more people worldwide than previously thought, but the number of deaths has fallen rapidly as efforts to combat the disease have ramped up.

The researchers, from UQ and the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, say that deaths from malaria have been missed by previous studies because of the assumption that the disease mainly kills children under 5.

"Despite assumptions that mainly young children die from malaria, our study identified that 42 per cent of malaria deaths occur in older children and adults," Dr Lopez said.

The study found that more than 78,000 children aged 5 to 14, and more than 445,000 people ages 15 and older died from malaria in 2010, meaning that 42 per cent of all malaria deaths were in people aged 5 and older.

While the overall number of malaria deaths is higher than earlier reports, the trend in malaria deaths has followed a similar downward pattern, due to anti-malaria drugs and insecticide-treated bed nets driving mortality down.

"We have seen a huge increase in both funding and in policy attention given to malaria over the past decade, and it's having a real impact," Dr Lopez said.

"Reliably demonstrating just how big an impact is important to drive further investments in malaria control programs. This makes it even more critical for us to generate accurate estimates for all deaths, not just in young children and not just in sub-Saharan Africa."

Starting in 1985, malaria deaths grew every year before peaking in 2004 at 1.8 million deaths worldwide. Since then, the number of deaths has fallen annually and, between 2007 and 2010, the decline in deaths has been more than 7 per cent each year.

The study's lead author and Director of the IHME, Dr Christopher Murray, said the study's finding that many more adults are dying from malaria is surprising.

"You learn in medical school that people exposed to malaria as children develop immunity and rarely die from malaria as adults," said Dr Murray said.

"What we have found in hospital records, death records, surveys and other sources shows that just is not the case."

(Source: The University of Queensland (UQ): The Lancet)