Five million children die every year — but most of these deaths could be prevented. Understanding why children die is one of the most important steps toward reducing global child mortality.

In a new analysis, researchers from Our World in Data examined the leading causes of death among children worldwide using data from the Global Burden of Disease study. Their interactive visualization reveals major differences between countries and age groups, while also highlighting how many of these deaths are avoidable with better healthcare, vaccination, nutrition, and safety measures.

In 2023, around 4.7 million children under the age of five died globally. More than 40% of these deaths were linked to infectious diseases such as pneumonia, malaria, diarrheal illnesses, and measles. Another 42% were caused by birth-related complications, including premature birth, neonatal suffocation, and infections during the first weeks of life.

Respiratory infections were the leading infectious cause, responsible for approximately 667,000 deaths, while malaria caused more than 400,000 child deaths worldwide. Premature birth complications accounted for more than 620,000 deaths.

The data also show a sharp contrast between low- and high-income countries. In Nigeria, infectious diseases remain the dominant cause of child mortality, accounting for more than half of all deaths among children under five. Malaria alone caused nearly one in five child deaths there in 2023. Researchers note that many of these deaths could be prevented through vaccination, access to treatment, and improved maternal and newborn care.

In higher-income countries such as the United Kingdom, infectious diseases are far less common causes of childhood death. Instead, most deaths are associated with complications related to premature birth and congenital conditions. Nearly 40% of child deaths in the UK were linked to preterm birth complications.

The causes of death also change as children grow older. Among children aged 5 to 14, injuries become much more significant. Road accidents, drowning, and other injuries account for nearly one-third of deaths in this age group worldwide. Childhood cancers also represent a substantial share.

Researchers emphasize that progress is possible. Over recent decades, deaths from childhood cancer and traffic accidents have declined sharply in many countries thanks to medical advances, vaccination programs, and improved public safety measures.

According to the authors, reducing child mortality begins with understanding where, why, and how children are dying — and using that knowledge to guide prevention efforts and healthcare investments.