Vaccines for children and programs aimed at maternal and child health have dramatically reduced death among young children.

But what about adolescents? The World Health Organization says their health is being neglected.

"When you look at adolescents, by that I mean the age group 10 to 19, we're finding 1.2 million die each year.

That's 3,000 deaths a day, that's, you know, 10 jumbo jets."

Here a family mourns the death of a 14-year-old girl, a WHO study finds most of the adolescents' deaths could be avoided.

The report says more than 2/3 of the deaths occur in sub-Saharan Africa and Southeast Asia.

This is the funeral of a child bride in Afghanistan.

Of all deaths, traffic injuries top the list, most kids are struck by a car while walking or riding a bicycle.

In India, for example, there are 90,000 deaths on the road each year; many of those are adolescents and children.

The causes of death differ by gender, age and region.

Boys between the age of 15 and 19 are more likely to die from traffic injuries than girls or younger boys.

Girls are more likely to die in childbirth, their body are not ready to have babies.

This play in Kyrgyzstan is meant to discourage the practice of child marriage.

Girls between 10 and 14 are at risk from respiratory infections like pneumonia that they get breathing in fumes from cooking fuels.

Teens who abuse alcohol or drugs, or those with mental health issues often cannot get the care they need to save their lives.

The WHO wants governments and health agencies to develop plans to improve the health of adolescents.

Governments have got to invest in young people. I mean, what's the countries' richest asset?

It's the young people, it's the children, actually, because they're the future."
Governments could create and enforce speed limits and make using seat belts mandatory.

Health agencies could encourage adolescents to develop healthy life styles.
The roots of diabetes, of heart attacks, of strokes, of lung cancer, the root of that lies in the adolescent years, how adolescents approach nutrition, and diet and exercise, whether they start to smoke or not, or abuse other substances."

Improving the physical, mental and sexual health of adolescents could result in significant economic returns, according to a study published in The Lancet in April.

The study reports that an investment of $4.60 per person per year would yield more than 10 times as much in benefits to society.