Man sitting on a case in a forest holding a cup from a thermos flask in his hand. He is gazing into the distance through trees with a small cloud of condensed breath in front of his face.

Respiratory system

The air passes through the mouth and nose, down the throat, past the larynx and vocal cords, and through the bronchial tubes into the lungs. From there, oxygen is released into the blood. Conversely, carbon dioxide is released from the lungs into the respiratory system for exhalation. Respiratory system disorders can hinder this vital process – and thus affect the body as a whole.

COVID-19: overview

COVID-19 is caused by an infection with SARS‑CoV‑2. The disease may be mild or very severe. Observing the public health rules and getting the coronavirus vaccine are important preventive measures.


Pneumonia typically brings on a sudden high fever, coughing and breathlessness. People without any pre-existing conditions normally recover after a few weeks.

Acute bronchitis

With acute bronchitis, the lower airways (bronchi) become temporarily inflamed. Initially, there is a dry cough but phlegm may later be coughed up from the airways.


An allergy occurs when the immune system has an overly sensitive reaction to a harmless substance such as plant pollen. There are various ways to treat an allergy.


Asthma is a chronic disease that causes a narrowing of the airways. An asthma attack makes breathing difficult. Asthma is treated effectively with medication.

Chronic obstructive pulmonary disease (COPD)

A persistent cough is the most obvious outward sign of chronic obstructive pulmonary disease (COPD). It develops gradually over several years.

Lung cancer

Lung cancer is one of the most common types of cancer. Around 57,000 people get lung cancer every year in Germany.

Hay fever

Many children and adults are affected by hay fever in the spring and summer months, when plants grow and bloom. It is caused by an allergic reaction to pollen in the air, affecting the upper airways.

Swine flu

Flu is a common respiratory infection in pigs, caused by influenza viruses that occur primarily in these animals. In rare cases, people can become infected and ill as a result.

Severe acute respiratory syndrome (SARS)

SARS is an infectious disease of the lungs, which is caused by the SARS-CoV coronavirus. The virus first appeared at the end of 2002 and spread to more than 30 countries until the middle of 2003.

Bird flu (avian influenza)

Bird flu (avian influenza) primarily affects birds but can also be transmitted to humans through close contact with infected birds. Infection is rare but often has severe symptoms.

Inflammation of the epiglottis (epiglottitis)

Inflammation of the epiglottis is usually caused by bacteria. Immediate treatment is required, as it can cause acute shortness of breath.


Acidosis is a condition in which the body’s pH balance is disrupted. As a result, the pH value of the blood drops and becomes “acidic”. This acidity is usually due to an underlying illness.

Pleural effusion

Pleural effusion is a build-up of fluid in the pleural space, i.e. the area between the lungs and the chest wall. Shortness of breath and chest pain are typical signs.

Cystic fibrosis

Cystic fibrosis is a rare, congenital metabolic disorder that cannot be cured. Treatments can help improve patients’ quality of life and life expectancy.

Legionnaires’ disease

Legionnaires’ disease (legionellosis) is a respiratory disease caused by bacteria. It may or may not be accompanied by pneumonia. The source of infection is contamination of the water supply.

Pulmonary embolism

A pulmonary embolism is usually caused by the blockage of a lung artery, for example if a blood clot from circulating blood has got into the lung. It is an emergency.


Anthrax is a rare disease. It is transmitted to humans by animals. Certain occupational groups are at high risk of contracting the disease. Read more about symptoms, causes, and treatment.

Hantavirus infections

Hantaviruses cause a flu-like illness with fever. It often also affects the kidneys. Rodents such as rats and mice and their droppings are carriers of the virus.

Whooping cough (pertussis)

Whooping cough is a highly infectious communicable disease that is triggered by bacteria. The disease can put severe stress on the body and is lengthy.

Tuberculosis (TB)

Tuberculosis (TB) is a bacterial infectious disease most commonly affecting the lungs. It is relatively rare in Germany.

Common cold

The first signs of a common colds are often sneezing and a sore throat. If rhinitis has fully kicked in, many people feel weak and ill.

False croup

False croup is a condition in the airways. It usually occurs in small children. Typical symptoms include a barking cough, a rasping sound when breathing in, and a slight shortness of breath.

Flu (Influenza)

Many people talk about the flu when they have a common cold. But the infections progress in different ways: a cold develops slowly, the flu quickly and fiercely.

Dust mite allergy

In dust mite allergies, it isn’t the dust itself that causes the symptoms. Instead, the symptoms such as sneezing are triggered by substances that are mainly found in the dust mites’ feces.

Obstructive sleep apnea (OSA)

People with obstructive sleep apnea (OSA) find it difficult to breathe while sleeping and have their breathing interrupted – usually without noticing it. So sufferers are very sleepy during the day.

Animal allergy

In an animal allergy it is not the fur that causes a reaction, but proteins that are found in the animal’s saliva, for instance. Avoiding contact with the animal can help, as can taking medication.

Pneumonic plague

It is true that the plague is now rare, but it has not been completely eradicated. Pneumonic plague may occur on its own or as a result of bubonic plague.