Researchers at The Johns Hopkins University Bloomberg School of Public Health say infectious diseases caused two-thirds of the nearly 9 million child deaths globally in 2008.
Experts at WHO and UNICEF's Child Health Epidemiology Reference Group analyzed data from 193 countries and found child deaths declined globally in the last decade, but millions of children under age 5 die from preventable causes every year.
"These findings have important implications for national programs," Dr. Mickey Chopra, UNICEF chief of health says in a statement.
"The persistence of diarrhea, pneumonia and malaria, all of which are easily preventable and curable but which nonetheless remain the leading single causes of death worldwide, should spur us to do more to control these diseases."
The findings are published in The Lancet.