World Tuberculosis Day is observed on 24 March each year to commemorate the day in 1882 when Robert Koch announced his discovery of Mycobacterium tuberculosis as the causative agent of tuberculosis, making it possible to diagnose and treat the disease. The goal of the day is to raise public awareness of the devastating health, social and economic consequences of tuberculosis and to intensify efforts to end the global epidemic.

Tuberculosis remains one of the world’s deadliest infectious diseases. According to the World Health Organization (WHO), nearly 4,500 people die from tuberculosis every day, and about 30,000 people (including about 700 children) die from a preventable and curable disease. It is estimated that global tuberculosis control efforts have saved 54 million lives and reduced the tuberculosis mortality rate by 42% since 2000.

Tuberculosis can be defined as a disease caused by Mycobacterium tuberculosis, a bacterium that almost always affects the lungs. It is curable and preventable. Tuberculosis is spread from person to person through the air. When a person with pulmonary tuberculosis coughs, sneezes, or spits, he or she expels tubercle bacilli into the air. Although your body can harbor the bacteria that cause tuberculosis, your immune system can prevent you from getting sick. For this reason, a distinction is made between:

• Latent tuberculosis. You are infected with tuberculosis, but the bacteria in your body are in an inactive state and you have no symptoms. Latent tuberculosis is not contagious. However, it can become active tuberculosis, so treatment is important.
• Active tuberculosis. Also called tuberculosis disease, this condition makes you sick and, in most cases, can spread to others. It can occur weeks or years after infection with tuberculosis bacteria. Signs and symptoms of active tuberculosis include:
  • Cough that lasts three weeks or longer.
  • Coughing up blood or mucus.
  • Chest pain or pain when breathing or coughing.
  • Unintentional weight loss.
  • Fatigue.
  • Fever.
  • Night sweats.
  • Chills.
  • Loss of appetite.
  • Tuberculosis can also affect other parts of the body, including the kidneys, spine, or brain. When tuberculosis occurs outside the lungs, the signs and symptoms vary depending on the organs involved.

There are two types of tests used to detect tuberculosis bacteria in the body: the tuberculin skin test and blood tests. A positive tuberculin skin test or blood test only indicates that the person is infected with tuberculosis bacteria. It does not indicate whether the person has latent tuberculosis infection (LTBI) or has progressed to tuberculosis disease. Other tests, such as a chest X-ray or sputum sample, are needed to determine whether the person has tuberculosis disease.

When a case of tuberculosis is diagnosed and reported, a contact investigation is conducted in the patient’s environment to rule out other possible cases of infection or disease and, if necessary, to begin appropriate treatment as soon as possible. The Centers for Disease Control and Prevention recommends that persons at increased risk for tuberculosis be screened for latent tuberculosis infection. This recommendation includes people who:

• Have HIV/AIDS
• Use intravenous drugs.
• Are in contact with infected persons.
• Are from a country where tuberculosis is common, such as several countries in Latin America, Africa, and Asia.
• Live or work in areas where tuberculosis is common, such as prisons or nursing and convalescent homes.
• Work in health care and treat people at high risk for tuberculosis.
• Have children exposed to adults at risk for tuberculosis.

Without treatment, tuberculosis can be fatal. This active, untreated disease usually affects the lungs, but can also spread to other parts of the body. It is important to remember that proper treatment of tuberculosis is the best way to control the disease. The treatment of tuberculosis has two main objectives: to interrupt the transmission of the disease by acting on the people who are infected (so that they do not get sick) and to treat the sick to prevent them from transmitting the disease, curing their illness, and preventing them from developing complications. It is essential to complete treatment and not to discontinue it in order to avoid relapse and the emergence of drug-resistant tuberculosis, which is much more difficult to treat and more likely to cause complications.

Tuberculosis also remains a leading cause of death due to the rise of drug-resistant strains. Over time, some tuberculosis bacteria have developed the ability to survive in spite of drugs. This is partly due to people not taking the drugs as prescribed or not completing treatment. Drug-resistant strains of tuberculosis occur when the antibiotic is not effective and does not kill all the bacteria. The surviving bacteria become resistant to that drug and often to other antibiotics.

It is important to remember that tuberculosis remains a major public health problem and that it is essential to complete the contact tracing study and not to stop treatment until it is completed. This is the most important action that can be taken. If treatment is stopped early, tuberculosis bacteria have the potential to develop mutations that allow them to survive the most effective anti-tuberculosis drugs. The result is drug-resistant strains that are more deadly and much harder to treat. It’s in everyone’s hands!