Tuberculosis is an infection caused by the Koch bacillus, it primarily afflicts the lungs and it is contagious, healthy persons receiving the infection if living or working in the same place with the infected person. By coughing, the infected person spreads the germs into the air, and others inhale them.
One way to diagnose TB is by performing a skin test called the intra-dermal reaction of tuberculin. The person that is suspected to be or to have been infected with TB is considered to have developed a hypersensitivity to the TB germ.
The test consists in injecting into the skin a purified protein derived from the TB germ. After more then 48 hours the skin area will present a bump. If the bump is large, the test is considered to be positive, meaning that the TB infection has occurred.
Even if the test is negative, it should be repeated after a while, because the test is not a 100 percent accurate.
Another method of diagnosing TB is performing a thoracic X-Ray which shows where in the lungs is the infection localized and how greatly it is expanded.
If the suspect person coughs, doctors take the sputum and with the help of the microscope they search for the TB germs in the sputum. This is quite an accurate method of diagnosing TB.
After diagnosing TB, doctors have to test what drugs will be most efficacious against the particular strain of the TB bacteria, using genetic engineering techniques like polymerase chain reaction (PCR).
To prevent the spread of TB in other people, health authorities have ordered that every child to get a shot of the bacillus Calmette Guerin (BCG) vaccine. This is a vaccine prepared of a weakened Tb germ, and it is considered to be the most effective vaccine in preventing childhood cases of TB.
Other general preventing methods of spreading the TB is hospitalizing the infected person, and practically isolating it from those who are healthy. Treatment must be followed at least 6 months continuously because interrupting the treatment could lead to spreading the disease in other organs, like: kidneys, intestinal tract, and lymph nodes, and even leading to the death of the infected person.
In treating TB, doctors use a combination of antibiotics because because only one drug could lead to the bacterial resistance to this drug. The drugs used nowdays are: isoniazid, rifampin, pyrazinamide, and ethambutol, in different combinations.
Generally if the treatment is followed all the way, a person can heal without problems, and reintegrate within the society in about 6 to 9 months.