Tuberculosis: The Ultimate Killer

Tuberculosis is one of three deadliest infectious diseases in the world. The AIDS virus annually takes approximately about three million lives and malaria about one million.

The vast majority of people (90%) infected by tuberculosis have so called latent and asymptomatic tuberculosis. Probability of transformation of latent tuberculosis into active one is about 10%.

Decreased immune resistance caused by AIDS significantly increases the likelihood of tuberculosis development. It’s considered that is the main reason for dramatically increased number of infected in Asia and Africa in last few decades.

In developed countries of Europe and America frequency of tuberculosis also grows, especially among the people of lower social status, drug addicts and long-time prisoners.

Despite those daunting figures tuberculosis is now much less widespread than it was among archaeological and historical populations of 18th and 19th century. A poet John Bunyan then said that tuberculosis is truly “captain of the dead” who destroys the whole families.

John Bunyan

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Information’s from England in the early 19th century shows that 25% of all deaths were caused by tuberculosis. A hundred years later tuberculosis was still responsible for 17% of all deaths in France. The intensity of fear from tuberculosis we can see in popular literature and music of that time. Almost every opera, book and novel mentions tuberculosis as synonym for death or something in that context.

Since the middle of 19th century the frequency of tuberculosis in Europe and America is gradually dropping for even today unknown reasons. Some scientist’s think that tuberculosis was a part of natural selection of that time which couldn’t be or destined to be stopped.

In 1882 Robert Koch isolated the cause of tuberculosis but first vaccinations with BCG (Bacillus Calmette-Guerin) vaccines began to be implemented in 1922. Successful treatments of tuberculosis started in 1946 by discovery and mass usage of streptomycin antibiotic.

     Robert Koch                          Bacille Calmette-Guerin                            BCG Vaccine

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The cause of tuberculosis is micro bacteria which has several variants. The Mycobacterium bovis causes tuberculosis in cattle and can be transmitted on humans by consuming milk that wasn’t pasteurized or with eating infected meat. That happens in rare cases.

Much often cause of tuberculosis is Mycobacterium tuberculosis which is spreading directly from human on human, usually trough respiratory system. Infected person transmits the disease by coughing, sneezing and speaking or singing. Spreading of disease is possible only if tuberculosis is in active state. So if someone have latent one it’s safe to interact.

Probability of infection depends on multiple factors: the time spent with infected person, virulence of germs and immunological capacity of person.

Tuberculosis starts to develop when its germs reach the lungs. Lungs are the main center of disease which very soon progress and spreads on lymph nodes. In most modern cases lungs heal up without any consequences. If the lungs don’t recover tuberculosis can spread on kidneys, brain and bones causing various deformations and finally death.

X-ray of advanced bilateral pulmonary tuberculosis

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