Pneumonia is the leading cause of death among children under 5, according to a new study led by researchers at the Johns Hopkins Bloomberg School of Public Health. They examined the distribution of child deaths globally by cause in 2010 and found that 64 percent were attributable to infectious causes and 40 percent occurred in neonates. The authors' findings, published in the May issue of the Lancet, suggest a decline in the total number of deaths between 2000 and 2010, however, they caution the decline is not sufficient enough to reach Millennium Development Goal number 4, which seeks to reduce child mortality by two-thirds in 2015.
"The numbers are staggering," said Robert Black, MD, MPH, senior author of the study and the Edgar Berman Professor and chair in the Bloomberg School's Department of International Health. "Of 7.6 million deaths globally in children younger than 5, 1.4 million or 18 percent were a result of pneumonia, 1.1 million or 14 percent were related to preterm birth complications and 0.8 million or 11 percent were a result of diarrhea. Despite tremendous efforts to identify relevant data, the causes of only 2.7 percent of deaths in children younger than 5 years were medically certified in 2010. National health systems, as well as registration and medical certification of deaths, need to be promoted and strengthened to enable better accountability for the survival of children."
Researchers updated the total number of deaths in children ages 0-27 days and 1-59 months and applied the deaths by cause to their corresponding country. To calculate the numbers, they used vital registration data for countries with an adequate vital registration system; applied a multinomial logistic regression model to vital registration data for low-mortality countries without adequate vital registration and used a similar multinomial logistic regression with verbal autopsy data for high-mortality countries. To generate regional and global estimates, the team aggregated country results. Researchers found that although the burden of deaths among children younger than 5 decreased by 2 million between 2000 and 2010, continued reduction at this rate would not reduce child mortality by two-thirds between 1990 and 2015 as outlined by the United Nations' Millennium Development Goal number 4. Among the causes of death that decreased globally, uncommon causes such as tetanus, measles and AIDS dropped at an annual rate sufficient to attain Millennium Development Goal number 4, and in Africa, malaria experienced a similar reduction.
"Pneumonia, measles and diarrhea contributed the most reduction between 2000 and 2010, however, the reduction was not significant enough to achieve Millennium Development Goal number 4," said Li Liu, PhD, MHS, lead author of the study and an assistant scientist with the Bloomberg School's Department of International Health. "Among the 3 leading causes of death from 2000-2010, diarrhea declined the fastest at 4 percent, followed by pneumonia at 3 percent and preterm birth complications at only 2 percent. Child survival strategies should direct resources toward the leading causes of child mortality, with attention focusing on infectious and neonatal causes."
The authors suggest, "More rapid decreases from 2010-2015 will need accelerated reduction for the most common causes of death, notably pneumonia and preterm birth complications. Continued efforts to gather high-quality data and enhance estimation methods are essential for the improvement of future estimates."
"Global, regional, and national causes of child mortality: an updated systematic analysis for 2010 with time trends since 2000," was written by Li Liu, Hope L. Johnson, Simon Cousens, Jamie Perin, Susana Scott, Joy E. Lawn, Igor Rudan, Harry Campbell, Richard Cibulskis, Mengying Li, Colin Mathers, and Robert E. Black.