In thinking about problems that currently affect developing nations, I try to remember that the US was a developing nation not so long ago.
Malaria once plagued the American south and Midwest. It's the reason English colonists abandoned the Jamestown, Virginia settlement for somewhere with fewer mosquitoes. In 1946, the Centers for Disease Control were formed to fight malaria. Five years later, malaria was eradicated in the United States. (Source)
In her memoir Little House on the Prairie, Laura Ingalls Wilder describes her family's experience with the disease in 1870:
Laura tried to get up, but she was too tired. Then she saw Ma's red face looking over the edge of the bed. Mary was all the time crying for water. Ma looked at Mary and then she looked at Laura, and she whispered, "Laura, can you?"
"Yes, Ma," Laura said. This time she got out of bed. But when she tried to stand up, the floor rocked and she fell down. . . . She knew she must get water to stop Mary's crying, and she did. She crawled all the way across the floor to the water-bucket. There was only a little water in it. She shook so with cold that she could hardly get hold of the dipper. But she did get hold of it. She dipped up some water, and she set out to cross that enormous floor again.
It drives me crazy when people say child mortality is saving us from environmental disaster. Do they wish that for their own families? Do they feel they have too many siblings, too many cousins, and we really ought to get some contaminated water or intestinal parasites in this country to deal with the problem?
No one wants that for their family. We want low child mortality and reasonable family size. Developed nations made that transition, but it took a while.
Hans Rosling does an excellent job at making public health statistics understandable to non-statisticians. I recommend his talk on "The good news of the decade”, especially for its comparison of child mortality rates across nations (at 8:40). Rosling notes that his home country of Sweden had a high child mortality rate in 1800, twice as high as anywhere now. Over time, with better education and better public health, the rate declined to its current low level. Most countries are currently on this journey of decreasing family size and child mortality, many of them progressing faster than Western countries ever did. (The site Gapminder lets you play with the charts yourself.)
While it's clear that large family size is correlated with child mortality, I'm not as convinced as Rosling is that lower child mortality is the main cause of smaller families. I gather it's a combination of fewer child deaths, female education, access to birth control, and urbanization.
The Ingalls family were typical 19th-century Americans – they had five children, one of whom died in infancy. I come from a typical 20th-century American family with two children, both still alive. I'm thrilled we made this demographic transition. My hometown no longer has malaria. I'm educated, I drink clean water, and I control my own fertility. When I choose, I will raise one or two children who will probably also be quite healthy.
We've come a long way. Now I want this life for everyone.