The world is doing a much better job of keeping babies alive long enough to become children, children alive long enough to become teens and teens alive long enough to fully grow up, according to a report in today's JAMA Pediatrics. "I think that the overall highlight of the report is good news," says Dr. Nicholas J. Kassebaum, an author of the report by members of the Global Burden of Disease Child and Adolescent Health Collaboration. "Without exception child mortality has improved throughout the world for the last 25 years."

But it's not all good news. The children in poor countries who might have died as babies or toddlers a few years ago live long enough to suffer from the effects of birth defects or develop mental health problems or cancer. And increasingly, they live long enough to bear the burden of war and violence in their countries.

We talked with Kassebaum, of the Institute for Health Metrics and Evaluation at the University of Washington in Seattle, about how child and adolescent health has changed since 1990.

First the good news: Deaths of children and adolescents to age 19 were nearly cut in half, from 14.2 million deaths in 1990 to 7.3 million deaths in 2015. How did that happen?

A big part of that is improvement in vaccine coverage, in care for mothers during their pregnancy and in nutrition. Beginning in about the late 1980s, there was a global mobilization around the rights of the child. That brought together experts and a lot of governments saying that children should have a right to health, to education, to a life with opportunities. There was an increase in all kinds of things: development assistance, aid for HIV, immunization efforts, and efforts to help pregnant women. It was a synergistic effort. A lot of programs focused on children under five, so for the last two decades there has been enormous progress in young children not dying as much.

A couple of countries stand out for the progress they're making: Ethiopia and Malawi, for example. What have they done to bring about improvements?

Those two countries have made improvements in clean water supplies and in better sanitation practices. They've also taken really concerted efforts in trying to reach universal vaccine coverage. They also made strides in expanding education. Not so much health education but general education. We know that if moms are more educated, that correlates with women being more likely to be involved in the workforce, with women being more empowered in their own health care and the health of their children, and more in tune with their own nutrition and that of their families. So education is not a direct link to improved childhood health, but it sets things in motion for improved health.

When children can be better protected through their first five years, what life and death challenges do they face as they grow older?

The way it's gone so far is absolutely the way it should go: really focusing on vaccines, clean water, sanitation and antenatal care.

But once those are in place, and the children get older, the challenges become much more complex. You have lots of children surviving past their early years. But many of these countries may not have the necessary resources to have comprehensive childhood education. They may not be able to deal with congenital birth defects or cerebral palsy and childhood cancer and mental health disorders that start to crop up in later youth. A lot of countries are doing really well in reducing infectious diseases and providing better nutrition but haven't gotten to the point where they can manage the more complicated cases.

What kinds of complicated things happen after a child makes it safely through infancy?

It varies by location and age. In the youngest kids, a big problem is congenital birth defects, and the biggest of those is congenital heart disease, such as infants born with holes in their hearts or defects in heart valves. There's also sickle cell disease, an inherited disease of misshapen red blood cells that inhibits oxygen from reaching tissue, in sub-Saharan Africa. Those kids are more susceptible to getting sick and needing care early.

And then when you get to be older, pediatric cancer is a big problem. The treatment of common childhood cancers in the U.S. and Europe and Japan has been remarkable. But that has required a well-functioning health system. That's not available in poor countries. Even a lot of middle-income countries in Latin America have not seen improvements in the treatment of childhood cancer.

Then during adolescence, you see more injuries: road traffic accidents, drownings, self-harm and suicide are big problems. Systems are not in place to deal with immediate injuries. When girls get into adolescence, they start getting pregnant. Early teen pregnancy is still common in the developing world. Pregnancy-related death is one of the biggest risks in adolescent females.

Were there surprising findings in the report?

One thing that flies under the radar is the effect of war. In the Middle East, the biggest cause of death for all kids over the age of 5 in 2015 was the effects of war. [According to the report, "The direct mortality burden of war was extremely large in North Africa and the Middle East, where it ranked second for each sex among children aged 1 to 4 years and first in all subsequent age groups in 2015."] Then there are the long-term effects of war: PTSD, some injuries that affect children for the rest of their lives and the consequences of families being separated.

What's the purpose of a report like this, looking at the global health of children over time?

It's a kind of report card. For the last two decades, enormous progress has been made. Children under five are not dying as much. But you have to think of childhood and adolescence as a continuum. We have to continue to address the health challenges of all children and adolescents.

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