Ars Technica has an interesting article about a recent conference in Germany that asked, what are the biggest challenges for global health? The conferees picked out "peak child" as a major one. As Ars Technica reports:
The majority of the world's nations now look very much like the industrialized world, with small family sizes and life expectancies of around 70 years and up. Many of them, however, have gotten there without the sort of economic growth that preceded a graying population in the industrialized world. As a result, one of the big challenges in global health is now caring for an older population on a low budget.
The trends were driven home by the Karolinska Institute's Hans Rosling, who relied on graphs that can be created using a site called Gapminder.org. These track various demographic features of most of the world's nations, such as life expectancy, GDP per capita, etc. The plots can be rolled forward and backward in time, and individual countries can be traced as changes occur. Rosling used a series of these graphs to demonstrate a number of points about the trends that have taken place over the past century.
Rosling started with a plot of family size vs. life expectancy; in the 1960s, the industrial world occupied the upper-left corner of the graphs below, with small families and longer life expectancies. Track forward to today, and all but a few African countries (many of which are suffering from HIV epidemics) have made their way to the upper left of the graph. Now, as he pointed out, Bangladesh is where Germany was in the 1960s. For adults, the greatest risk of death is in traffic accidents; for children, it's drowning. "The world has gotten better," Rosling declared. "It's bullshit to say otherwise."
The net result is that we reached what he termed "peak child" in about 2005. The world used to be dominated by the population in the lowest age brackets. That's now starting to shift—with the biggest chunk of the population now being in adolescence. The world isn't getting gray just yet, but, as Rosling put it, "we now just have adult population growth."
But that's going to pose some significant challenges, since Bangladesh hasn't tracked Germany exactly. If you plot life expectancy against GDP/capita, you'll see that Bangladesh's growing life expectancy hasn't been paralleled by economic growth. Similar things are happening all over the globe; Vietnam now has a life expectancy that US had during Vietnam war, but its purchasing power is where the US was during its Civil War. "We've never had a point in our history where countries have modern life expectancy illnesses without the income to support treatments," Rosling concluded.
This isn't to say that diseases related to abject poverty weren't a problem; there are certainly areas of the globe with failed governments or persistent poverty that don't have the basic nutrition and sanitation to see these sorts of extended life expectancies. But, in general, those have become the exceptions.
The whole article is well worth reading.