Nutrient deficiencies double risk of malaria deaths in children

A large percentage of child deaths related to malaria are attributable to undernutrition and deficiencies of vitamin A, zinc, iron and folate, according to a new report from Johns Hopkins researchers.

They found that mildly malnourished children were twice like to die from malaria than children who are not undernourished, with the risk increasing with greater malnutrition.

The review of recent data from malaria endemic regions shows that improving child nutrition could prevent more malaria-related illnesses and deaths than previously thought.

"While undernutrition's role in exacerbating diarrheal disease and respiratory infections is well known, scientific evidence has been mixed regarding its role in malaria infection," explained lead author Laura Caulfield, an associate professor with the Johns Hopkins Bloomberg School of Public Health's Center for Human Nutrition.

"Despite the fact that people have thought that undernutrition prevents malaria, the bulk of evidence suggests that undernutrition contributes significantly to the malaria burden," she added.

Nearly 550,000 annual malaria deaths are attributable to underweight in children less than five years of age, according to global burden of disease data published earlier this year.

The investigation, described in a supplement to this month's American Journal of Tropical Medicine and Hygiene, looked at malaria morbidity and mortality risk due to underweight and specific micronutrient deficiencies in countries including The Gambia, Vanuatu, Ghana, Guinea-Bissau and Senegal.

While underweight children had only a slightly increased risk of a clinical malaria attack, the data on mortality risk in underweight children were dramatic. Mildly malnourished children were twice like to die from malaria than children who are not undernourished, while moderately malnourished children were four times more likely to die. Severely malnourished children were nine times more likely to die.

While the risk of malaria mortality increases with the severity of undernutrition, most child deaths occur in only mildly to moderately undernourished children, because of the high prevalence of children of this nutritional status in many countries, revealed the research.

Widespread zinc and vitamin A deficiencies in malaria endemic regions compromise a child's ability to fight infection. Zinc improves growth and enhances the body's ability to respond to infection, and vitamin A plays an essential role in the immune response and is believed to be necessary for host resistance to malaria.

The researchers stress that strategies to reduce the global malaria burden must include integrated nutrition programmes that address growth faltering and improve the micronutrient status of young children.

"We still need more research to better understand the complex relationship between nutrition and malarial infection but the existing and emerging evidence strongly suggests that well-nourished children are better able to fight and survive malaria infection," said Dr Caulfield.