Tuberculosis: The Not So Ancient Disease

“If the importance of a disease for mankind is measured by the number of fatalities it causes, then tuberculosis must be considered much more important than those most feared infectious diseases, plague, cholera and the like. One in seven of all human beings dies from tuberculosis.” –Robert Koch, 1882

Consumption, the white plague, the white death, the wasting disease and phthisis pulmonaris are some of the many names for one of the deadliest diseases from ancient times, tuberculosis (TB). The industrial revolution of the 18^th and 20^th centuries led to a significant increase in the population, unsanitary living conditions, and overpopulation in most industrial booming towns and cities. This quick urban growth led to a heightened exposure to the disease, making it epidemic in much of Europe, North and South America, and African and Asia.  At its height TB reached a prevalence of more than 900 deaths per 100,000 in the 18^th century, killing more people in the last 200 years than any other disease. Its high prevalence rates (up to 100% in certain populations) gave it a spot light amongst some of the deadliest diseases in history such as the bubonic plague, cholera, measles, smallpox, and typhus. Despite its chronic condition in adults, in children and infants the disease would often manifest in acute forms killing them within days or weeks of infection.

In 1865 a French military physician, Jean-Antoine Villemin, successfully managed to inoculate rabbits with TB, thus implying that TB was contagious. At that moment in time contagion was viewed as a radical ancient notion that simply could not exist in civilized societies. Accepting the existence of such notions would instill fear in the masses and prejudice against those who had or were suspected of having the disease.  Several years later on March 24, 1882 scientist Robert Koch introduced his findings on the causes of tuberculosis to the scientific community, revolutionizing medical science. By culturing the Mycobacterium Tuberculosis pathogen from diseased tissue and staining it he had managed to isolate the one disease that was killing more people than any other at the time. Not only did he isolate it, but also succeeded in culturing, and inoculating laboratory animals, essentially, reproducing the disease. Koch successfully established a relation of cause and effect between the bacillus and the disease, setting in motion an etiological revolution.  However, it would be another 64 years before soil biologist Selman Waksman developed streptomycin, the first effective antibiotic against Tuberculosis.

“After the presentation, Koch’s audience sat in stunned silence, needing some time to allow the realization to sink in that the mystery of humankind’s deadliest disease had just been unraveled.” – Historical Perspectives on the Etiology of Tuberculosis, David Barnes Ph.D.

With more than one hundred and thirty years of research since then, TB has been tested, studied, and documented.  Once known as the ‘deadliest disease’ scientists concur that even the most hopeless cases of TB are treatable and curable for adults. Yet, TB remains an opportunistic disease in people with HIV and a leading cause of death in many places around the world. In adults, once contracted, the disease can often lay dormant for years where it is subsequently exposed to children, who are far more susceptible to the disease. Often the onset of symptoms is hard to detect before it’s too late, while the tests used for diagnosis don’t produce accurate results. TB is diagnosed using a sputum test that analysis mucus from the lungs.  However, children often don’t produce enough mucus for an adequate sample. A missed diagnosis can be deadly, since the disease can spread from the lungs into the brain and bone marrow of a child, killing them before the first physician visit.

A timeless disease, TB continues to plague a significant percentage of humankind. According to the World Health Organization, tuberculosis is second only to HIV/AIDS as the greatest killer from a single infectious agent.  Despite this knowledge many people still do not believe that it can affect them, and that the time of TB has long since passed. Common misconceptions about TB include the differentiation between the infection and the disease, it’s current effect on a global scale, and who can contract the disease. TB infection and TB disease are significantly different. The world is broken up into three separate categories: those who do not have TB, those who are infected with TB, and those whose infection has developed into the TB disease. According to the CDC a misconception about TB is that it is no longer a major public health problem. In fact, of the 7 billion persons in the world, 2.3 billion are already infected with TB, and about 9 million develop TB disease each year. Furthermore, TB causes about 1.4–2 million deaths annually. In 2008, the Charlotte County Health Department in Florida created an info flyer with some of the most common misconceptions of disease. It debunks the stigmatization against individuals associated with poor hygiene and low economic status as being the sole contractants of TB, some patients actually have no identified risk factors and should not be ruled out because of this preconceived notion of who a TB patient is.

References:

Johnston W.D., in: Kiple K.F. (Ed.), Cambridge World History of Human Disease, Cambridge University Press, Cambridge, 1993, pp. 1059–1068.

Barnes, D. S. 2000. Historical perspectives on the etiology of tuberculosis. Microbes Infect. 2: 431-440.