Tuberculosis: Captain of the Men of Death
May 24, 2023
Tuberculosis (TB) is a disease caused by a bacterium, Mycobacterium tuberculosis, that are spread from person to person through aerosols created when a person with disease of the lungs or throat coughs, sneezes, or speaks. When people nearby breathe in these bacterial aerosols, they may become infected. TB usually affects the lungs, but the disease is not limited to the lungs and can affect other parts of the body, such as the brain, the kidneys, or the spine.
The term “tuberculosis” was coined by Johann Schonlein in 1834 but it is an ancient human disease. TB was widespread in ancient Egypt and has been recognized in Egyptian mummies by palaeopathological changes, such as Pott’s disease, and Mycobacterium tuberculosis complex DNA has been detected and characterized from the Predynastic era (2), the Old, Middle and New Kingdoms (3). In 1825, clear evidence of TB was shown in an ancient Egyptian mummy, Irtyersenu. She was called ‘Dr Granville’s mummy’ and was the first ancient Egyptian mummy subjected to a scientific autopsy. Irtyersenu of the 26th Dynasty was aged about 50, from the necropolis of Thebes and dated to about 600 BC. Molecular re-examination of tissue was done, and a medical diagnosis was provided by a team of scientists in 2010(1). Palaeopathology and ancient DNA analyses showed clear evidence for Mycobacterium tuberculosis complex DNA in lung tissue and gall bladder samples, based on nested PCR of the IS6110 locus. It was concluded that tuberculosis is likely to have been the major cause of death of Irtyersenu.
As an ancient disease, TB has had its share of names. Ancient Greeks called it “phthisis” , ancient Romans called it “tabes”, and the ancient Hebrew term for it was “schachepheth”. Due to the pale appearance of patients, it was called “the white plague” in the 1700s. Even after Schonlein named it tuberculosis, TB was commonly called “consumption” in the 1800s. During the Industrial Revolution in the 18th and 19th centuries, overcrowded living conditions and poor sanitation facilitated the spread of TB. Due to the devastating effect on its victims, TB was referred to as the “Captain of all these men of death.”
The modern names for TB indicate the location of the disease: pulmonary, extrapulmonary. In addition, it also refers to possible treatments: drug-susceptible, drug-resistant, multidrug resistant, and extensively drug-resistant.
TB is treatable and curable in most cases. However, without proper treatment, it can be fatal. Misuse and mismanaged treatment has led to the emergence of multidrug resistant (MDR TB) and extensively drug resistant TB (XDR TB). MDR TB organisms are resistant to at least isoniazid and rifampin, the two most potent TB drugs. XDR TB is a rare type of MDR TB that is resistant to isoniazid and rifampin, plus any fluoroquinolone and at least one of three injectable second-line drugs (i.e., amikacin, kanamycin, or capreomycin). These patients are left with very few and less effective treatment options. XDR TB is of special concern in immunocompromised patients and can result in higher mortality.
March 24 has been denoted World Tuberculosis Day and marks the discovery of Mycobacterium tuberculosis, the etiological agent of tuberculosis, by Dr. Robert Koch in 1882. With TB continuing to be a public health problem, this day cannot be called a celebration but rather an opportunity to create public awareness about this devastating disease and how it can be controlled (4).
According to the World Health Organization, there were an estimated 10 million cases and 1.4 million deaths in 2019. Efforts to control and prevent TB have included vaccination (with the Bacille Calmette-Guérin/BCG vaccine), screening and treatment of infected individuals, infection control measures in healthcare settings, and public health campaigns to raise awareness of the disease. Several global initiatives like the Stop TB Partnership and the Global Fund to Fight AIDS, Tuberculosis, and Malaria support TB prevention and control efforts.
Centuries after identification of Mycobacterium tuberculosis, TB remains a global health challenge that continues to affect millions and is one of the top ten causes of death worldwide and a major public health concern.
References:
2. https://pubmed.ncbi.nlm.nih.gov/9879471/
3. https://pubmed.ncbi.nlm.nih.gov/9365482/
4. https://www.cdc.gov/tb/worldtbday/history.htm
5. ZK Sagawa et al. Safety and immunogenicity of a thermostable formulation of the ID93 + GLA-SE tuberculosis vaccine candidate in healthy adults. Nature Communications DOI: 10.1038/s41467-023-36789-2 (2023).