Tuberculosis, or TB, has been around for centuries, is widely viewed as a disease of overcrowding and malnutrition today about 1.4 million people still die of TB. Tuberculosis is still the biggest single infectious killer, beaten only by HIV/AIDS, with 95% of cases in low income countries. Some victims of TB contract it as a result of other infections, such as the musician Tom Fogerty who was infected by a blood transfusion.
In the Western world, about one in five deaths were caused by it between the 17th and 19th centuries. Before antibiotics and improved sanitation made inroads, it was widely seen as a romantic illness, often affecting the young, who wasted away, often helped in this with the commontreatment of blood letting, by physicians. It is an illness that has had a huge impact on art, music and litereature, in a similar way that AIDS has in the modern age.
Famous victims include the Romantic Poet John Keats, composer Frederic Chopin, and novelists Emily Bronte and Robert Louis Stevenson, but some scholars think that the disease may be as old as humanity itself, and the Egyptian King Tutankhamun may also have suffered from it.
A detailed genetic study of 250 strains of the bacteria from around the world has shown that the disease originated with the emergence of our ancestors, the early homo sapiens, from Africa some 70,000 years ago.
This research also shows that early humans did not contract it from ther domesticated animals, as this was before farming developed. The leading author of the study, Inaki Comas said “This implies that the bacteria have been able to survive in small, unter-gatherer populations. At the same time we show that its evolution paralels with that of humans and benefists from human demographic explosions. ” As humans spread and multiplied, so did the bacterium.
I think these researchers should go visit a reconstructed Iron Age village, as I did at St Fagans Museum near Cardiff last year. The roundhouses of our ancesters could get incredibly smoky, and the only way to avoid the smoke was to sit low down, not a great lifestyle for healthy lungs, so the disease thrives in a combination of crowded living space but also smoky conditions, hence during the industrial revolution it became an epidemic.
Paralel research by 3 other teams of scientists show how the genetic mutations that have allowed the bacteria to become resistant to antibiotics, largely relegating it to a disease of the poor and underpriveliged. Some of the genes they have discovered were not known to be involved in resistance, so there may be new methods on the horizon for treating our long time companion.