Types of Diseases

Health is a state of physical, mental, and social well-being in which individuals are able to function at their best.

A disease is a condition that disrupts how the body functions and can lead to ill health. There are two types of diseases:

  • Communicable diseases
  • Non-communicable diseases

Communicable Diseases

Communicable diseases, also known as infectious diseases, are caused by pathogens such as bacteria, viruses, parasites, and fungi.

These diseases spread from person to person in different ways. For example, through the air in tiny droplets, through contact with bodily fluids like blood, saliva, or mucus, or through contaminated surfaces or objects.

Some common examples of communicable diseases include:

  • The common cold
  • Influenza
  • Measles


Another example of a communicable disease is tuberculosis, which is a bacterial infection that mainly affects the lungs. However, it can also affect other parts of the body, including the brain, kidneys and bones.

How tuberculosis spreads

Tuberculosis spreads through the air when an infected person talks, coughs, or sneezes. This releases tiny droplets containing the bacteria into the air. Other people can inhale these droplets. As a result, they may become infected if their immune system cannot fight off the infection.

Also, tuberculosis can spread through contact with contaminated surfaces or objects, such as doorknobs, and it can be transmitted through sexual contact.

Tuberculosis is more likely to spread in crowded or enclosed spaces where there is poor ventilation. This is because the bacteria can remain in the air for longer periods of time.

Symptoms of tuberculosis

Symptoms of tuberculosis can include:

  • A persistent cough (lasting longer than three weeks)
  • Chest pain
  • Coughing up blood
  • Fatigue
  • Weight loss
  • Fever

Treating tuberculosis

Tuberculosis can be treated with a combination of antibiotics. However, it’s important to finish the full course of treatment to make sure that the infection is completely gone and to prevent the development of drug-resistant tuberculosis.

Here you can learn about antibiotic-resistant bacteria.

Tuberculosis can be prevented through vaccination with the BCG vaccine and by practising good hygiene, which reduces the risk of infection.

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