Asthma and infections


Do infections cause asthma?

You may remember that your asthma seemed to start in connection with a viral infection probably when you were a child. However, the infection probably did not cause the asthma; more likely, it only triggered the symptoms. The condition was already there and would have developed sooner or later, with or without the infection. You were probably born with a tendency to develop asthma.


Some children are allergic and have a mild form of asthma (inflammation of the airways) without being aware of it. Then they get a viral infection and the obvious asthma symptoms appear.

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Do infections trigger asthma?

Yes, viral respiratory infections, such as the common cold or flu, can trigger attacks in people who have asthma. Try to avoid contact with people if you know they have a respiratory infection.


Viral infections are thought to be more likely to trigger symptoms if the underlying inflammation in asthma is not properly treated.

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Why dont antibiotics help against asthmatic inflammation in the airways?

Penicillin and other antibiotics are only effective against bacterial infections. The inflammation in asthma is not caused by bacteria, so antibiotics have no effect. In addition, most infections of the airways are caused by viruses, and would not respond to antibiotic treatment.


People with asthma can get bacterial infections in the lungs (bronchitis or even pneumonia), which may need to be treated with antibiotics. But antibiotics do not have any effect on the long-term, underlying inflammation in asthma. This inflammation needs to be treated with a controller (anti-inflammatory) medication. And since the inflammation usually also causes tightening of the muscles around the airways and narrowing of the airways, it should also be treated with an airway opener or reliever medication (bronchodilator).

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Is asthma contagious?

No. Asthma cannot be spread to other people. On the other hand, a person with asthma can catch bronchitis just as easily as anyone else. And bronchitis can be contagious, in the same way as an ordinary cold.

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