What is tuberculosis?
Tuberculosis is an infectious disease that is transmitted between people mainly by inhalation, that is, by inhaling droplets expelled by the sick person when coughing, talking or sneezing. When you inhale air with bacilli, they will settle in the lungs. It is caused by Mycobacterium tuberculosis, also known as Koch's bacillus. It is a serious but potentially curable disease.
What forms of tuberculosis are there?
There are three forms of tuberculosis:
- Pulmonary tuberculosis: the lung is the main organ affected by the disease, since the contact of the bacillus (belonging to the mycobacteria family) with the body is made by inhalation
- Extrapulmonary tuberculosis: the following organs can be affected: lymph nodes, pleura, meninges, pericardium, bones, kidneys, liver, intestines, skin, among others
- Disseminated tuberculosis: when the bacillus reaches the bloodstream, the whole body can be affected
What are the symptoms?
The symptoms of the disease are:
- persistent cough for more than 2 to 3 weeks
- tiredness
- slimming
- night sweats
- increase in body temperature at the end of the day (evening fever)
In pulmonary tuberculosis, the main symptoms are:
- Easy tiredness
- loss of appetite
- weakness
- slimming
- night sweats
- usually low fever of predominance at the end of the day and night
- persistent cough, often with yellowish or greenish sputum and which may contain blood
In extrapulmonary tuberculosis, there are a wide variety of complaints, depending on the organ affected.
Do all those infected have symptoms?
No. When bacilli inhaled during inspiration reach and settle in the lungs, one of the following situations may occur:
- Through their natural defenses, the individual is able to eliminate bacilli from the lungs
- Appearance of symptoms when the bacillus overcomes and overcomes natural defenses – tuberculosis disease
- There are no symptoms, but the bacilli can remain inside the body for long periods of time – latent tuberculosis
How is it transmitted?
Tuberculosis is mainly transmitted through the air through the inhalation of droplets, expelled by the sick person when breathing, coughing, talking or sneezing. When you inhale air with bacilli, they will settle in the lungs.
Are all forms of tuberculosis contagious?
No. Patients with pulmonary tuberculosis who release the bacillus into the air during breathing, talking, coughing or sneezing can become infected. Forms of extrapulmonary tuberculosis are not contagious.
How can I prevent it?
Tuberculosis can be partially prevented and avoided. If you have had contact with a TB patient, you should be screened. Go to your health center and talk to a professional. It may also be indicated for preventive treatment.
The patient and those around him can act in order to prevent contagion, namely, by:
- Wearing a mask
- Ensure physical distancing conditions in a well-ventilated space exposed to sunlight
- The tuberculosis bacillus is very sensitive to the action of ultraviolet rays
- ensure good hygiene, housing and nutrition
People at risk, including close contacts of patients with respiratory tuberculosis, should be screened for tuberculosis, which consists of a clinical assessment, lung x-ray, tuberculin skin test and/or IGRA test. Preventive treatment consists of regimens of one or two antibiotics in periods between 3 and 9 months.
Who is most at risk of getting TB?
Generally, only 10% of infected people develop the disease, and this risk is higher in immunocompromised populations, namely young children, people infected with human immunodeficiency virus (HIV) or taking immunosuppressive medication.
Risk groups are people:
- at the extremes of age (children and the elderly)
- malnourished
- with AIDS virus infection
- with diabetes
- com cancer
- whose medication compromises natural defenses, such as chemotherapy or long-term use of corticosteroids
- with chronic lung diseases
- patients taking biologic or immunosuppressive treatments
Children under the age of 6 exposed to tuberculosis have a high risk of developing the disease.
How is the diagnosis made?
The diagnosis of tuberculosis is based on the laboratory identification of Mycobacterium tuberculosis in organic products (sputum, most of the time). Confirmation of the disease and the susceptibility profile to antibacillary drugs allows the choice of the correct treatment.
Nowadays, microbiological and molecular biology tests are used, making it possible to diagnose the disease and the mutations that confer resistance to first-line antibacillary drugs.
What is the incubation period?
After infection with Mycobacterium tuberculosis, it takes an average of 4 to 12 weeks for the detection of primary lesions.
What is the treatment of tuberculosis?
Usually, tuberculosis is treated through the oral administration of drugs (first-line antibacillary drugs), which are provided free of charge at the Pulmonology Diagnostic Centers, which are differentiated health units in the area of tuberculosis.
The minimum duration of treatment is 6 months and the maximum can reach 24 months. Even so, the duration is the responsibility of the doctor, who evaluates case by case according to the severity and clinical evolution of the disease.
Where is tuberculosis treated?
The follow-up of patients, the screening of cohabitants and the treatment of the disease are preferably carried out in the Pulmonological Diagnostic Centers, spread throughout the country. Hospitalization is only proposed when clinical conditions require it.
Does the treatment have any side effects?
In most cases, the drugs used in the treatment of tuberculosis are well tolerated. The most common side effect is gastrointestinal intolerance.
Rare side effects are: allergic skin reactions, toxic effects on the liver, increased uric acid, blood disorders such as anaemia or reduced platelet count and joint pain.
If any side effect is suspected, the patient should consult their doctor, who will decide on possible changes or suspensions of therapy.
Is there vaccination for tuberculosis?
In June 2016, given the epidemiological evolution of tuberculosis in Portugal, it was decided to change the BCG vaccination strategy in Portugal and only children with individual or community risk factors for tuberculosis were vaccinated.
Source: Directorate-General for Health (DGS)