Dietary deficiencies are responsible for "a substantial proportion" of malaria-related sickness and death among children, according to researchers at the Johns Hopkins Bloomberg School of Public Health.
The researchers say that a lack of vitamins and minerals are to blame for the high numbers of children who fall prey to malaria, especially in sub-Saharan Africa. They say that many of these deaths are "entirely preventable", and recommend that nutrition programmes be integrated into existing malaria prevention strategies.
The team, led by Laura Caulfield, an associate professor at the school's Centre for Human Nutrition, reviewed data from Ghana, Guinea-Bissau and Senegal, and found a strong link between malnourishment and the likelihood of malaria being fatal in children under the age of five.
Even mildly malnourished children were twice as likely to die from malaria than children who are not undernourished, and moderately malnourished children were four times more likely to die. For children with severe malnutrition, the risk of death from malaria was nine times greater than in those who were well nourished.
The researchers say that deficiencies in dietary iron, zinc, vitamin A and folic acid appear to increase the threat that malaria poses to child health. These vitamins and minerals are important to the human body's immune system, but are often scarce in areas where malaria is rife.
The researchers estimate that zinc and vitamin A deficiencies in children under five may each be responsible for about 20 per cent of malaria deaths in that age group every year — a total of nearly 400,000 deaths. Ninety per cent of the deaths due to vitamin A deficiency are in Africa, they say.
Until now, scientists have disagreed about whether being undernourished makes malaria worse, better or has no effect. Indeed some studies have even suggested being undernourished protects individuals from malaria by making them unattractive hosts for the malaria parasite.
But the new research suggests that being well nourished enables children to mount a strong immune response and beat the infection.
However, Caulfield's team warns that famine victims may also be exposed to increased risks from malaria by re-feeding programmes. Such programmes, they say, allow the malaria parasite to multiply more rapidly in the body than the restoration of the individual's ability to resist the disease.
"In famine relief, it is recommended that malaria chemoprophylaxis is provided at the time of re-feeding and that the population is monitored carefully for malaria and provided with appropriate treatment," write the researchers.
The research by Caulfield and colleagues is one of 37 papers published in a special supplement of the American Journal of Tropical Medicine and Hygiene.
The supplement, which is being made available worldwide for no cost, is called The Intolerable Burden of Malaria II: What's New, What's Needed. It gathers research on malaria from around the globe and features papers on anti-malaria drugs, insecticide treated nets, and other approaches to malaria control in use or development.
Each year, malaria kills between one and two million people, mostly in sub-Saharan Africa.
Researchers interested in receiving a hard copy of the journal supplement or the associated DVD should contact the FIC Communications Office at [email protected]
Reference: American Journal of Tropical Medicine and Hygiene 71 (Suppl. 2), 55 (2004)