Tbc Health

Archive for the ‘Treatment of Tuberculosis’ Category

Tuberculosis is a germ infection caused by Mycobacterium tuberculosis which generally affects the lungs, but it can also affect kidneys, lymph nodes, spine, intestinal tract and brain.

Tuberculosis is spreading by air, if an infected person coughs sneezes or shouts, the germs spreading into the air. By inhaling them other people get infected.

After the discovery of the BCG vaccine and of the antibiotic treatment of TB, the number of TB cases declined in the early 1980’s and experts thought that the disease would be eradicated by 2010. But between 1985 and 1991 more and more cases of TB were discovered in US. Since 1992, in US, the number of reported cases declined continuously and so, in 2004 there was a 46% drop of reported cases from 12 years earlier.

One of the reason why tuberculosis has spread so quickly lately is the increased number of patients infected with HIV. HIV leads to a weakened immune system, and so, TB has a free way to develop, and passes quickly from the primarily stage to the secondary stage.
The germ can reactivate if a person has a weakened immune system like in the cases of AIDS, post surgery, after other infections, in miners and foundry workers, and in those who have scars of healed tuberculosis.

Also, the risk of catching TB increases with the frequency of contacting other infected people, with miserable living conditions and with poor nutrition.

Another factor that helps tuberculosis to spread is the fact that some patients do not finish their antibiotic treatment. This treatment must be followed a long period of time (6 to 9 months), and often, if patients feel better they interrupt the treatment, believing that they are cured, but this is only an illusion, because TB germ is still alive, can activate instantly and spread itself to other healthy people. This fact also could lead to the mutation of the germ that becomes multi drug resistant, and does not respond properly to the known treatment, and so, scientists must discover new efficient drugs.

Nowadays people have businesses to take care of, and they have to travel a lot. Tourism as well has developed and gained a lot of interested people in this activity. All these activities can lead to a contamination with the TB bacterium and its transportation back home where healthy people are.

In preventing Tb from spreading, governments need to develop special international measures and communicate with people. Also, regular controls should be made along with the education for health.

As any other health problems tuberculosis needs to be treated. While treating is not as easy at it seams, specialists tried to develop a vaccine to prevent it. Nowadays we know a vaccine for tuberculosis that is called BCG or Bacille Calmette Guerin. This vaccine was first used in 1921 and it is the only vaccine available in our days for protection against tuberculosis. Some categories of people, such as children are more protected than others after taking this vaccine.

The development of the vaccine took place in the beginning of the last century when Calmette and Gurein, two scientists from the Institute Pasteur isolated a live attenuated strain of Mycobacterium bovis. This strain was subcultured every three weeks for many years. After about thirteen years it was proved that the strain was less virulent for animals such as cows or guinea pigs. During all those years of research some genetic changes occurred to the original strain o Mycobacterium bovis. Those altered organisms were called BCG.

Nowadays there are several strains of BCG. As a vaccine against tuberculosis, BCG was first used n 1921. The cultures of BCG were distributed later to several laboratories all over the world where the vaccine strain called BCG continued to be cultured. After a while it was proved that the strain spread all around the globe had no longer identical genetic properties. Even the original strain maintained in Paris continued his change. To limit these changes the organism is maintained in several laboratories using a seed lot production technique to limit the genetic variations using freeze-dried cells so that each batch starts with the same cells.

Since the day of its first usage more than 1 billion people used this vaccine. It is known that for the first time this vaccine was given to children, after extensive tests in animals.

Until now, no problems seemed to occur after the usage of this vaccine, but the specialists believe that persons who are immune compromised might be at risk for developing serious infections caused by the BCG itself.

A tragic accident took lace in Lubeck where more than 25 % of the children that received this vaccine developed tuberculosis. Later it was proved that this was an accident and the cause of the created situation was a batch contaminated with a virulent strain of M. tuberculosis.

The BCG vaccines that are in use at this moment are produced in different areas throughout the world and it is known that they are not identical