Tuberculosis is an infectious disease that has been known and present since the first appearance of man on Earth.
Some prehistoric animal fossil remains have shown the presence of this bacterium. Several scientific studies have taken place that have tried to understand whether tuberculosis originated in animals and then made the "species jump" to humans or vice versa.
Some researchers have sequenced the common ancestral ancestor by geolocating it in West Africa about 40,000 years ago. By that time, Homo Sapiens populations had already begun migrations to the Asian continent and Australia.
In more recent research published in Nature Genetics, entire genomes of Mycobacterium tuberculosis complex (MTBC) were sequenced, with the goal of characterizing global diversity and reconstructing the evolutionary history of the TB pathogen. The results were outstanding: MTBC was localized to the African continent about 70,000 years ago, at the height of the Middle Paleolithic period.
In addition to "recent" skeletal findings (4000 B.C.) that showed men with tuberculosis, the first to describe the disease was Hippocrates in the 5th century B.C.: the disease was widespread in the population with very dangerous effects such as fever and hemoptysis (the emission with coughing of blood from the respiratory tract). It was only thanks to Avicenna in the 10th century AD, with his "Canon of Medicine," that we had the first descriptive documentation of the infectious disease and the detail of prevention through quarantine to limit contagion.
The pathogen was described scientifically by Robert Koch (1882), a Nobel laureate in 1905: the Mycobacterium Tuberculosis.
The first major therapy saw the use of streptomycin (1946), but previously rest was prescribed in places called "sanatoriums" with a suitable climate.
One therapy used was artificial pneumothorax, the machinery allowed the injured or even collapsed lung to rest of the injuries sustained, to promote their resolution.
The 1980s were marked by two important events that affected the course of tuberculosis:
- the emergence of strains resistant to antimicrobial therapy;
- the emergence of HIV, which assumed it as the first comorbidity.
In the 19th century it was defined, given the historical period, as a romantic disease called the "evil of living": suffering from tuberculosis granted the privilege of greater "sensitivity." Young men and women of the nobility purposely "whitened" their faces in order to be defined as "sick" in a kind of purity through noble disease-death (an Italian example was Giacomo Leopardi).
Byron in 1828 reported in his writings that he would have liked to die of tuberculosis, and George Sand proudly called Chopin the "Tisic Lover": the one who coughed gracefully. Let's also not forget "The Lady of the Camellias" (Dumas son) and "Les miserables" (V.Hugo) with all the ideal of the disease.
Tuberculosis thus increased in popularity, becoming the disease of the true artist.
The great Koch after working on anthrax (Bacillus anthracis was his discovery) published, in 1882 his work on mycobacterium and the date of March 24 was identified since then as World Tuberculosis Day.
In Italy as in Europe much attention was devoted to the importance of Koch's bacillus. In the 1930s many sanatoriums dedicated to these patients were built
.A gigantic work was the one in Sondalo, in 1932, 8 inpatient pavilions and 1 surgical were built, the buildings were nine stories connected to the road network and immersed in a wooded area.
The detection of tuberculous leptomeningitis in Homo Erectus fossils found in Turkey showed human involvement for TB as early as 50,000 years ago. This was confirmed by the great tuberculosis scholar Giorgio Besozzi (pulmonologist) who said that the bacterium was one of the first living organisms that humans had to evolve with, living with. Famous are his words "Man was born and disease was already waiting for him!".
To focus on the danger of this disease, 2013 figures count 1,500,000 deaths worldwide of which 350,000 are infected with HIV. The two figures are impressive when compared to the number of infections: 9,000,000 highlighting the role of partners of the most important sexually transmitted disease.
STOP TB is the most dangerous disease in the world.
STOP TB, the medical network coordinated by WHO, estimates that 4,500 people die every day worldwide. The humanitarian involvement about which little is told.
In South America, and more specifically in Peru, Chaky oncay (Inca) is being studied, thus furthering the search for tuberculosis: the "Tuberculosis" study group of the Universidad San Marcos in Lima at the Institute of Med. Tropical "Daniel A. Carrion" is furthering research on new vaccines and the study on antibiotic resistance, a support from Italy is the dermatological collaboration for cutaneous tuberculosis.
All over the world today, the greatest attention is being paid to this infectious disease, which, among its cousins, is the greatest cause of morbidity and mortality. Many tests show that about 80 percent of residents in several African and Asian nations test positive for tuberculin.
It is estimated that one quarter of the world's population is affected by latent TB infection, as our immune system can cope with the disease and the microorganism remain silent for years. Infected individuals may not develop the disease, have no symptoms and do not give infection. Some will end their lives without having developed the disease, others will get sick after years.
Actively developing the disease are highlighted at-risk individuals such as:
- HIV positive;
- subjects who use drugs;
- subjects with medical conditions, diabetics or malnourished;
- infants and children;
- elderly people.
Developing countries are certainly the most at risk, due to the poor living conditions (food shortages and poor nutrition) of some segments of the population and poor hygiene conditions. All factors that affect the immune system and the lowering of its levels.
Let's briefly recall that Mycobacterium Tuberculosis is a gram-positive, aerobic bacterium that is transmitted through droplets (flugge) of saliva emitted by infected individuals, by coughing, sneezing, and phonation. It usually affects the lungs by destroying the alveoli (at the end of the bronchioles) but other organs can also be involved such as lymph nodes, glands, bones, intestines, urinary tract, and the skin.
Typical symptoms of pulmonary TB are dry cough, fever, chest pain, sweating, weight loss and also hemoptysis, which is blood with sputum.
For preventive purposes, the application of proper hygiene and maintaining a balanced diet are recommended.
To limit infection, the key action is early diagnosis. Diagnosis is made by the Mantoux test (or tuberculin skin test) with further investigations, such as sputum microscopy (for bacterial), chest X-ray and CT scan. The Quantiferon test on venous blood has now increasingly replaced the Mantoux.
Therapy, typically 6-8 months, includes molecules such as: isoniazid, rifampin, streptomycin, pyrazinamide, ethambutol. As anticipated more and more antibiotic resistance continues to be recorded, one form is known to resist isoniazid and rifampin.
Correct drug intake must be verified, and the pathological course must be monitored with periodic examinations and checks.
Vaccination with BCG, consisting of a live attenuated bovine Tbc strain, does not always work in adults and cannot be used in infants with HIV; in the latter, it may result in the onset of the disease. Data report that its protective efficacy is therefore higher in children than in adults. The vaccine was put into production in 1921 and is administered to young children in nations with a high incidence of tuberculosis. Vaccination prevents severe childhood forms.
In Italy it is administered to a few at-risk groups.
Scientific research has been at a standstill for decades both in developing an alternative vaccination to BCG and in improving greater efficacy of the vaccine itself. In recent years, innovative projects are emerging in many parts of the globe, which gives us hope for creating new therapies to reduce the spread of this bacterium.
