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 by researchers with the Johns Hopkins Bloomberg School of Public Health.
Their review of recent data from malaria endemic regions showed that improving child nutrition could prevent more malaria-related illnesses and deaths than previously thought. Their paper appears in the August 2004 supplement to the American Journal of Tropical Medicine and Hygiene.
“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 E. Caulfield, PhD, an associate professor with the 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.”
Nearly 550,000 annual malaria deaths are attributable to underweight in children less than 5 years of age, according to global burden of disease data published earlier this year. The investigators 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 2 times more like to die from malaria than children who are not undernourished, while moderately malnourished children were 4 times more likely to die. Severely malnourished children were 9 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.
Widespread zinc and vitamin A deficiencies in malaria endemic regions contribute to growth faltering and 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. Researchers stress that strategies to reduce the global malaria burden must include integrated nutrition programs 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,” Dr. Caulfield urged, “but the existing and emerging evidence strongly suggests that well-nourished children are better able to fight and survive malaria infection.”
“Undernutrition as an underlying cause of malaria morbidity and mortality in children less than five years old” was written by Laura E. Caulfield, Stephanie A. Richard and Robert E. Black.