Mucus in the bronchial tubes when you have bronchitis
Excess mucus in the bronchial tubes

What is bronchitis?

Bronchitis occurs when the bronchioles (air-carrying tubes in the lungs) are inflamed and make too much mucus. There are two basic types of bronchitis:

  • Chronic bronchitis is defined as cough productive of sputum that persists for three months out of the year for at least two consecutive years. The cough and inflammation may be caused by initial respiratory infection or illness, exposure to tobacco smoke or other irritating substances in the air. Chronic bronchitis can cause airflow obstruction and then is grouped under the term chronic obstructive pulmonary disease (COPD).
  • Acute or short-term bronchitis is more common and usually is caused by a viral infection. Episodes of acute bronchitis can be related to and made worse by smoking. Acute bronchitis could last for 10 to 14 days, possibly causing symptoms for three weeks.

What is the difference between bronchitis and pneumonia?

In terms of symptoms, these two diseases may seem very similar. Both cause cough, fever, fatigue, and a heavy feeling in your chest. Bronchitis can sometimes progress to pneumonia.

Despite similarities, the conditions are different. First, bronchitis involves the bronchial tubes, while pneumonia affects the alveoli, or the air sacs in the lungs. Second, pneumonia symptoms are usually much worse. In addition, pneumonia can be life-threatening, especially in older people and other vulnerable groups.

If your symptoms do not get better in a week or so, it is best to contact your doctor.

What causes bronchitis?

Usually, acute bronchitis is brought on by a viral infection, though it may also be caused by a bacterial infection. The flu and colds are examples of viral infections.

Chronic bronchitis is usually, but not always, caused by smoking tobacco. It can also be caused by exposure to secondhand cigarette smoke, air pollution, dust, or toxic gases. Your risk can be increased by family history of bronchitis, having asthma and allergies, and having gastroesophageal reflux disease (GERD).

What are the symptoms of bronchitis?

Symptoms of bronchitis include:

  • A cough that is frequent and produces mucus.
  • A lack of energy.
  • A wheezing sound when breathing (may or may not be present).
  • A fever (may or may not be present).
  • Shortness of breath.

Is bronchitis contagious?

Acute bronchitis can be contagious because it is usually caused by infection with a virus or bacteria. Chronic bronchitis is not likely to be contagious because it is a condition usually caused by long-term irritation of airways.

How long are you contagious if you have acute bronchitis?

If you have begun taking antibiotics for bronchitis, you usually stop being contagious 24 hours after starting the medication. If you have a viral form of bronchitis, antibiotics will not work. You will be contagious for at least a few days and possibly for as long as a week.

How is acute bronchitis spread?

If bronchitis is caused by a viral or bacterial infection, it is spread the same ways that colds are spread—by germs traveling through the air when someone coughs or sneezes. You can breathe the germs in if you are close enough. You could also touch something that has germs on it, like a door, and then transfer the germs by touching your nose, mouth or eyes. That is why good hand washing practices are important for adults and children.

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