Tuberculosis - History

History

Tuberculosis has been present in humans since antiquity at the latest. The earliest unambiguous detection of M. tuberculosis involves evidence of the disease in the remains of bison dated to approximately 17,000 years ago. However, whether tuberculosis originated in bovines, then was transferred to humans, or whether it diverged from a common ancestor, is currently unclear. A comparison of the genes of M. tuberculosis complex (MTBC) in humans to MTBC in animals suggests humans did not acquire MTBC from animals during animal domestication, as was previously believed. Both strains of the tuberculosis bacteria share a common ancestor, which could have infected humans as early as the Neolithic Revolution. Skeletal remains show prehistoric humans (4000 BC) had TB, and researchers have found tubercular decay in the spines of Egyptian mummies dating from 3000–2400 BC. Phthisis is a Greek word for consumption, an old term for pulmonary tuberculosis; around 460 BC, Hippocrates identified phthisis as the most widespread disease of the times. It was said to involve fever and the coughing up of blood, which was almost always fatal. Genetic studies suggest TB was present in the Americas from about the year 100 AD.

Before the Industrial Revolution, folklore often associated tuberculosis with vampires. When one member of a family died from it, the other infected members would lose their health slowly. People believed this was caused by the original person with TB draining the life from the other family members.

Although the pulmonary form associated with tubercles was established as a pathology by Dr Richard Morton in 1689, due to the variety of its symptoms, TB was not identified as a single disease until the 1820s, and was not named tuberculosis until 1839 by J. L. Schönlein. During the years 1838–1845, Dr. John Croghan, the owner of Mammoth Cave, brought a number of people with tuberculosis into the cave in the hope of curing the disease with the constant temperature and purity of the cave air; they died within a year. Hermann Brehmer opened the first TB sanatorium in 1859 in Sokołowsko, Poland.

The bacillus causing tuberculosis, Mycobacterium tuberculosis, was identified and described on 24 March 1882 by Robert Koch. He received the Nobel Prize in physiology or medicine in 1905 for this discovery. Koch did not believe the bovine (cattle) and human tuberculosis diseases were similar, which delayed the recognition of infected milk as a source of infection. Later, the risk of transmission from this source was dramatically reduced by the invention of the pasteurization process. Koch announced a glycerine extract of the tubercle bacilli as a "remedy" for tuberculosis in 1890, calling it 'tuberculin'. While it was not effective, it was later successfully adapted as a screening test for the presence of presymptomatic tuberculosis.

Albert Calmette and Camille Guérin achieved the first genuine success in immunization against tuberculosis in 1906, using attenuated bovine-strain tuberculosis. It was called bacillus of Calmette and Guérin (BCG). The BCG vaccine was first used on humans in 1921 in France, but only received widespread acceptance in the USA, Great Britain, and Germany after World War II.

Tuberculosis caused the most widespread public concern in the 19th and early 20th centuries as an endemic disease of the urban poor. In 1815, one in four deaths in England was due to "consumption". By 1918, one in six deaths in France was still caused by TB. After determining the disease was contagious in the 1880s, TB was put on a notifiable disease list in Britain, campaigns were started to stop people from spitting in public places, and the infected poor were "encouraged" to enter sanatoria that resembled prisons (the sanatoria for the middle and upper classes offered excellent care and constant medical attention). Whatever the (purported) benefits of the "fresh air" and labor in the sanatoria, even under the best conditions, 50% of those who entered died within five years (circa 1916).

In Europe, rates of tuberculosis began to rise in the early 1600s to a peak level in the 1800s, when it caused nearly 25% of all deaths. Mortality then decreased nearly 90% by the 1950s. Improvements in public health began significantly reducing rates of tuberculosis even before the arrival of streptomycin and other antibiotics, although the disease remained a significant threat to public health such that when the Medical Research Council was formed in Britain in 1913, its initial focus was tuberculosis research.

In 1946, the development of the antibiotic streptomycin made effective treatment and cure of TB a reality. Prior to the introduction of this drug, the only treatment (except sanatoria) was surgical intervention, including the "pneumothorax technique", which involved collapsing an infected lung to "rest" it and allow tuberculous lesions to heal. The emergence of MDR-TB has again introduced surgery as an option within the generally accepted standard of care in treating TB infections. Current surgical interventions involve removal of pathological chest cavities ("bullae") in the lungs to reduce the number of bacteria and to increase the exposure of the remaining bacteria to drugs in the bloodstream, thereby simultaneously reducing the total bacterial load and increasing the effectiveness of systemic antibiotic therapy. Hopes of completely eliminating TB (cf. smallpox) were dashed after the rise of drug-resistant strains in the 1980s. The subsequent resurgence of tuberculosis resulted in the declaration of a global health emergency by the World Health Organization in 1993.