Tuberculosis (TB) has infected humans since ancient times with evidence of TB found in the bones of Egyptian mummies from as early as 3000 BC. In the medieval period deaths from TB were blamed on vampirism with the slow decline in health thought to literally be the life being sucked from victim. It wasn’t until Robert Koch discovered the bacteria responsible in 1882 that a true cause was identified.
The large-scale migration to cities during the industrial revolution led to its endemic increase and TB is usually associated with nineteenth and early twentieth century urban poverty. One in seven people died from TB before the discovery of antibiotics in the 1940s. In particular it was endemic in urban areas amongst the working and more impoverished classes who lived and worked in close quarters. TB is spread through droplets in the air arising from the cough of an infected person. For those who caught the disease there was only a 20% chance of survival. There was no cure before antibiotics and stays in sanatoria were prescribed to allow patients to recover in isolation from the population in places with clean fresh air. The richer you were, the nicer the sanatoria, with Davos in the Swiss Alps popular with the more wealthy patients. TB was called consumption or the white plague in the nineteenth century and was romanticised as a disease because it led to a slow death. Novels, operas and films depict it this way with heroines delicately coughing into handkerchiefs and dying gracefully in Les Miserables, La Traviata and Moulin Rouge. The romantic poet Lord Byron even wrote that he would like to die from consumption. The reality is certainly not so romantic.
The decline in TB in the twentieth century mirrored improvements in living and working conditions amongst the poor and the advent of antibiotics to treat it. Today the death rates have improved but 1.5million people worldwide still die of TB and 9.6 million people contracted it in 2014. TB is becoming more problematic as the number of cases that are antibiotic resistant increase and the percentage of deaths from those infected by TB is expected to rise again unless new treatments are found. In Ireland there are around 400 cases each year. People who are most susceptible are smokers, people with diabetes and HIV, and people on immunosuppressant drugs.
Researchers at Trinity College Dublin however have made a breakthrough in potential new avenues of TB treatment. 25% of Europeans have a different form of a protein called Mal which makes this group more susceptible to contracting TB but until now it wasn’t clear why. Interferon Gamma is described by the group like putting a fire-lighter on a fire – it sets off a strong immune response to an infection like TB. The group discovered that the different form of Mal affects how strongly your body responds to Interferon Gamma as it is involved in cell signalling in response to the Interferon Gamma. This may help explain why individuals have different responses to TB. Some develop extreme symptoms which they die from, others recover after a time, and others who are exposed never develop any symptoms. Researchers now hope that optimised and personalised treatments could be developed to suit the individual based on this new information. It also has implications for other illnesses where Interferon Gamma is involved.