A new attempt to quantify malaria deaths over the past 30 years suggests the death toll, especially among adults, has been greatly underestimated. The figures also show the fragility of the gains made in fighting the disease.
Collecting data on malaria deaths is notoriously tricky; the countries where the disease is most prevalent have the weakest statistics. And even where causes of death were recorded, the researchers found many deaths were simply attributed to “fever” – probably malaria, but possibly not. In addition, a malaria infection is often a contributory cause of death along with other health problems.
However, after some complicated number-crunching, researchers, based at the Institute for Health Metrics in Seattle, believe they have produced the best estimates so far of how many people in the world die of malaria.
The figures, published in the London-based medical journal, The Lancet, some surprises, principally because they are significantly higher than those issued last year by the World Health Organization (WHO) – more than eight times higher in the case of older children and adults in Africa, where most of the deaths occurred. The difference was smaller in the case of children under five, but the researchers said they believed malaria was a more important cause of death in under-fives than the 2011 World Malaria Report estimated, causing 24 percent of child deaths in Africa.
Christopher Murray and his colleagues said they believed the fact that almost half a million extra deaths occurred in adults and older children each year had practical implications. “Traditional teaching in most medical schools argues that acquired immunity [in endemic areas] means that adults have clinical malaria, but are not likely to die from it. Inspection of the basic... data, however, clearly shows a substantial percentage of malaria deaths in individuals aged 15 years and over, even in endemic areas such as sub-Saharan Africa.”
In the light of this they suggest a shift of control strategies to pay more attention to all adults, not just women and children, in the distribution of insecticide-treated bed nets.
The research also tracked malaria deaths through time, from 1980 to 2010. Global malaria deaths almost doubled between 1980 and 2004; child deaths in Africa almost tripled over the same period. The researchers suggest the HIV/AIDS epidemic and resistance to chloroquine as probable causes, along with an increase in population in malaria-endemic areas.
After that the number of deaths started to fall, although they are still not down to 1980 levels. The results of hard-fought campaigns, and the resources provided by the Global Fund to fight AIDS, Tuberculosis and Malaria, do show up in the figures. The authors say “the risk of malaria death in several countries that have scaled up control efforts, such as Zambia, Tanzania, Kenya and Ethiopia, has decreased between 2000 and 2010 figures”.
The reverses of the 1980s and 1990s signal the fragility of the gains in the war against malaria, and the researchers say this underscores the danger posed by the world economic crisis, and the slowdown in health funding. They conclude: “The announcement by the Global Fund [in November] that their next round of funding would be cancelled raises enormous doubts as to whether the gains in malaria mortality reduction can be built on or even sustained.”
Sarah Kline, executive director of Malaria No More UK, told IRIN this fragility of funding, especially from the Global Fund, was a big source of discussion and anxiety for the whole malaria community. “The total funding gap for malaria, from all sources, if we are going to meet our 2015 targets, is around US$3 billion a year, although we did have some positive announcements at Davos about extra funding from the Gates Foundation, and the governments of Saudi Arabia and Japan.”
The funding gap was also addressed by the Liberian President Ellen Johnson Sirleaf when she was elected to head the African Leaders' Malaria Alliance on 2 February, and urged African countries to step up their own funding for control campaigns and find innovative sources of finance to close the gap.