Most of the improvement of disease outcomes over the past two centuries is due to better prevention rather than better treatments. And most of the things that prevent disease are done for comfort rather than for disease prevention. That is why many diseases decreased in the 1800s before scientists even realized that germs exist and cause infections! Public health was already improving because people didn’t like drinking sewage and wanted better foods and more comfortable housing with running water and sewage. Vanessa Heggie wrote that one of the first examinations of this trend was discovered in regards to the decline of tuberculosis.
[Tuberculosis] eventually killed [George Orwell] in 1950 at the age of just 47.
Tuberculosis was a major European health concern in the nineteenth and early twentieth century… At times it was probably the single biggest killer of young adults, feared particularly because it seemed to attack those in the prime of their lives. Treatments were varied and sometimes desperate: Sulfa-based drugs, open air treatment, bed rest, and surgery (including a phrenic nerve crush) were all tried on Orwell.
The first effective drug treatment for tuberculosis, streptomycin, was only released in 1947 – and it was too expensive for many sufferers (Orwell used the proceeds from the American sales of Animal Farm to fund his treatment). The first preventive, the BCG vaccination, was introduced in 1953.
We might expect that these drugs were crucial in the fight against tuberculosis, but in the 1960s and 1970s… Thomas McKeown argued that something else had caused the massive decline in deaths from this disease. In The Modern Rise of Population (1976) he did something deceptively simple: he plotted the rate of death from tuberculosis in England and Wales over time, and marked on the graph the introduction of drugs and vaccines… It’s immediately obvious that the major decrease in the disease happened long before streptomycin was invented.
McKeown argued that it was not drugs, or vaccines, or scientific medicine which conquered this infectious disease, but money [and]… the crucial factor was improved nutrition – this became known as the McKeown Thesis. Many doctors, biologists and pharmacologists rejected this conclusion… In particular the historian Simon Szreter has done some meticulous work on statistics and death records, and suggested that sanitary measures, clean water and public health are the real causes of the decline in tuberculosis mortality (he’s also made it clear how political this process of interpretation can be…)
Heggie points out that McKeown’s graph may overstate the reduction in tuberculosis mortality before antibiotics because of overdiagnosis, but McKeown’s overall point remains valid. Danika Barry reproduced the graph: