How we got to survive to retirement, continued

As you will recall, early in the 20th Century children stopped dying en masse from infectious diseases because of milk pasteurization, and chlorination of drinking water, both of which our current secretary of HHS objects to, evidently because he wants kids to die. Anyway, to continue . . .

 

Gains in life expectancy were temporarily set back by the 1918 influenza pandemic, but then resumed their relentless rise. You can see that the rise actually started to take off in 1890, before the widespread adoption of pasteurization and chlorination. The reasons for this are unclear but it’s generally believed that better nutrition was important. It probably didn’t hurt that doctors stopped bleeding and purging people, and adopted sanitary practices. Even if they weren’t doing much good, they were doing less harm. 

 

 

 

However that may be, although physicians led the way in campaigning for pasteurization and clean drinking water, medical intervention as such had little or nothing to do with that upward line until after WWII. We noted earlier that tuberculosis (TB) was the second leading cause of death in 1900. Pasteurization largely eliminated human cases of bovine tuberculosis from contaminated cow’s milk, but TB is mostly transmitted through the air. Nevertheless deaths from tuberculosis in the U.S. declined sharply and steadily throughout the 20th Century. There was no treatment for TB until 1944, but this had no discernible effect on the downward trend, which continued as before.

Knowledge of the contagious nature of TB resulted in some public health interventions that may have contributed to the decline. These included isolating people with TB in so-called sanatoria, and public education campaigns to discourage spitting. These probably had little impact, however.
 

So RFK Jr. is about 1% right in that people who are in better health are somewhat less susceptible to infectious disease. The biggest reason for the decline in TB deaths was indeed probably better living conditions. TB is an opportunistic infection that is most likely to strike people with weakened immune systems, which can be caused by malnutrition. The nutritional status of the population improved markedly throughout the early 20th Century and this is thought to be perhaps the biggest contributor to the decline in TB. Less crowded and better ventilated housing also likely contributed. (Effective antibiotic treatment of tuberculosis did not enter the picture until the 1950s.)

These factors may have contributed to declines in deaths from pneumonia and influenza as well. It’s hard to say because the influenza virus mutates constantly and its virulence and transmissibility vary from year to year. (Virulence means the severity of disease a pathogen is likely to cause, transmissibility is the likelihood of infected person infecting others.) After the WWI flu pandemic burned itself out, flu was much less a problem. But pneumonia is often caused by bacteria and, while it’s likely that better nutrition and living conditions also meant people were less susceptible to bacterial pneumonia, that effect was not as strong as the decline in TB infections.

Bacterial pneumonia can be a complication of influenza and other viral infections, or strike people who are debilitated for other reasons, including old age. I got pneumonia while I was recovering from my surgery, which is actually fairly common. Fortunately, by the time that happened to me, it was readily treatable with antibiotics, which is a damn good thing because I was very, very sick. (Oh yeah. The doctor gave me too short of a course and it recurred, so I had to start over. This is the best way to create antibiotic resistant strains of bacteria. We’ll have more to say about that later.) 

So sure, every physician and public health researcher and practitioner in the world agrees that among the essential keys to population health are good nutrition and healthy living conditions. That isn't some big secret that THEY have been suppressing. Before the 20th Century, aristocrats and kings on average lived no longer than peasants, because bacteria and viruses don’t care about your social class, and without vaccines and antibiotics, infectious diseases might kill fewer people than they did in the 19th Century but they'd still be leading causes of death and disability, surgery would be unsafe, and epidemics would periodically decimate the population. More on that next.