TUBERCULOSIS: stay informed

Health

GENERAL

What is tuberculosis?
Tuberculosis is an infectious disease caused by tuberculosis bacilli or bacteria called My-cobacterium tuberculosis. The most common form of tuberculosis is pulmonary tuberculosis (approx. 70% of cases). Other forms of tuberculosis, such as lymphatic tuberculosis or bone tuberculosis are not contagious.

What is latent tuberculosis infection?
A latent tuberculosis infection means that a person has, at some time in his life, been in contact with tuberculosis bacilli and has therefore been contaminated (infected). At this stage, the person is neither sick nor contagious. In most infected people (approx. 90%), tuberculosis never develops.

How is tuberculosis transmitted?
Tuberculosis bacilli are transmitted from person to person through the air. When coughing, the person with tuberculosis projects into the ambient air microscopic droplets which contain tuberculosis bacilli. These droplets stay in the air for a while and can therefore be breathed in by other people. But the risk of contamination only exists in the event of contact with a person suffering from contagious pulmonary tuberculosis.

When do we speak of a tuberculous disease or tuberculosis?
We speak of tuberculosis when the tuberculosis bacilli proliferate in the lungs, which can occur months or even years after contamination. Tuberculosis bacteria can also affect other parts of the body through the bloodstream (eg lymph nodes, central nervous system, bones). However, these forms of tuberculosis are not contagious. Tuberculosis is especially dangerous for young children and people with weakened immune systems. Today, tuberculosis has a good chance of being cured if treated correctly.

What are the typical symptoms of tuberculosis?
At first, the disease causes few painful symptoms: cough (sometimes bloody), fatigue, slight fever and night sweats. At an advanced stage, other symptoms may appear such as: weight loss, loss of appetite, chest pain.

When do we speak of contagious pulmonary tuberculosis?
We speak of contagious pulmonary tuberculosis when the disease has progressed to the point that the affected person expels tubercle bacilli when he coughs (or sneezes). It is only at this stage of the disease that the person with tuberculosis can infect other people (question 3).

How long can a person suffering from contagious tuberculosis infect other people?
A person suffering from contagious tuberculosis is placed in isolation in the hospital or at home, which means that they are kept away from those around them. She remains in isolation until she is no longer contagious, which is usually two to three weeks. After this time, it is no longer contagious. But she must continue her treatment, under medical supervision, for about six months or more until she is completely cured.

Who is at risk of being infected?
Only people who have very close contact (several hours in the same room) with a tuberculous and contagious person run a risk of contamination.

I was vaccinated against tuberculosis. Can I still be infected?
Yes, because the vaccinations against tuberculosis (BCG) of the past offer only very limited protection.

I had contact with a person suffering from pulmonary tuberculosis. What must I do now ?
The specialist tuberculosis service of the Cantonal Lung League will provide you with free advice and information on all aspects of tuberculosis. If you have been in very close contact with a person suffering from contagious pulmonary tuberculosis (question 6), you can make an appointment with this service (addresses in the appendix) to inform you and carry out a test which will show whether you have been contaminated.

I had contact with a person with tuberculosis other than pulmonary. What must I do now ?
Nothing ! You are in no danger. Such forms of tuberculosis are not contagious because the person with tuberculosis does not send out tubercle bacilli in the air if they cough.

How can a contagion be highlighted?
Contagion can be demonstrated by means of a tuberculin skin test or a blood test (also called interferon gamma test). The specialist tuberculosis service of the Cantonal Lung League will be happy to provide you with information on these tests and the interpretation of their results.

The result of the blood test is positive. What does this mean and what will happen now?
A positive test result means that contact with tubercle bacilli has occurred. The specialist tuberculosis service will inform you and your attending physician of this, asking you to agree on a date to carry out other examinations (X-rays, etc.) in order to be able to confirm or exclude tuberculosis.

I have been infected, can I put other people at risk?
No ! Contamination does not mean that you have tuberculosis or that you are contagious. So even if your blood test is positive, your loved ones are not in danger.

I have been infected. So what is the risk that I will later suffer from tuberculosis?
The tubercle bacillus is under control thanks to your immune system. It is therefore "dormant". 90% of all people infected do not develop tuberculosis. Only 10% of infected people develop the disease. Half of them develop tuberculosis within two years and the other half later in life. The risk increases when a person has a weakened immune system (for example, in the case of HIV infection, long-term cortisone treatment, immunosuppressive chemotherapy, diabetes or excessive consumption of alcohol and tobacco).