is bronchitis contagious?

August 12, 2024

Let's start first with what exactly is bronchitis. The bronchial tubes, which transport oxygen into and out of the lungs, are swollen due to inflammation. A thick mucus is then produced, which irritates the lungs and settles in your chest making you cough. It can be classified into two main types: acute bronchitis and chronic bronchitis.¹

• Acute: most often caused by viruses, sometimes bacteria.
• Chronic: often linked to irritants like smoking or environmental factors.

Is Acute Bronchitis Contagious?

Bronchitis itself, which is the inflammation of the airways, is not contagious. However, the viruses and bacteria that can lead to bronchitis can be contagious. For example, if you have the flu, you may also develop bronchitis. However, when your friend catches the flu from you, their airways do not always become inflamed like yours did.

Acute bronchitis is most often caused by a viral infection like the common cold or the flu. In fact, viruses cause up to 95 percent of all cases of acute bronchitis in healthy adults. ²

How Do Viruses Spread?

When a viral infection is in its active phase, it has the potential to spread through respiratory droplets released when an infected person coughs or sneezes. The viruses can also be contracted through contact transmission. This is when someone touches a contaminated surface, such as a doorknob, and then touches their eyes, nose or mouth. Then when a person contracts the flu or cold virus, it can cause inflammation and irritation in the respiratory tract, including the bronchial tubes. The virus can cause irritation to the lining of these tubes, leading to swelling and increased mucus production. As a result, the airways become narrowed, making it more difficult for air to pass through. This can cause symptoms such as coughing, wheezing, and shortness of breath. When the inflammation and mucus production are persistent, it can lead to the development of bronchitis.

Coughing is the most common symptom of bronchitis, which can be dry or produce mucus and usually goes away after a few weeks. Mucus color cannot predict whether an infection is viral or bacterial.²

Learn about bronchitis (and strep throat) symptoms and treatment

Is Viral Bronchitis Contagious?

Acute bronchitis, often triggered by viruses like the flu or the common cold, can be contagious. The viruses that cause acute bronchitis are easily spreadable from person to person. Viral acute bronchitis usually resolves within a few weeks without the need for antibiotics. Studies show that antibiotics for bronchitis won’t help otherwise healthy children and adults feel better.

Is Bacterial Bronchitis Contagious?

Bacterial bronchitis is typically not considered contagious in the same way that viral bronchitis is. Bacterial bronchitis is caused by a bacterial infection, rather than a virus. Bacterial infections are generally not as easily transmitted from person to person as viral infections. Bacterial infections can stem from a viral infection that has not been cured. Bronchitis happens when the bronchial tubes are aggravated, so any bacterial illness affecting the tubes can cause bacterial bronchitis.

However, it's important to note that the bacteria that cause bronchitis can still be spread through respiratory droplets when an infected person coughs or sneezes. So, while bacterial bronchitis itself may not be highly contagious, the bacteria responsible for the infection can potentially be transmitted to others.

To prevent the spread of bacterial bronchitis, it is still advisable for individuals with the infection to practice good respiratory hygiene, such as covering their mouth and nose when coughing or sneezing, and regularly washing their hands to minimize the risk of transmitting bacteria to others. Additionally, individuals who are at higher risk of complications from bacterial infections, such as those with weakened immune systems, or pre-existing pulmonary disease, may need to take extra precautions.

How Long is Bronchitis Contagious? The contagious period of bronchitis can vary depending on the type of virus involved. In general, individuals with bronchitis caused by viral infections are contagious for a few days, up to a week. It's important to note that since there are numerous viruses that can cause bronchitis, medical providers typically do not test for specific viruses. Therefore, it is best to assume that you could spread the disease while experiencing cold symptoms.

What's The Difference Between Bronchitis and a Cold? While the viruses that cause bronchitis and a cold can be similar, bronchitis often involves a more persistent and productive cough, as the virus has created inflammation in the chest. It may be accompanied by chest discomfort, which is less common with a simple cold. If symptoms worsen or last longer than a typical cold, it's advisable to seek medical advice.

Is Chronic Bronchitis Contagious?

No, chronic bronchitis itself is not contagious. Chronic bronchitis is a constant cough that lasts for three months or more and happens at least two years in a row. Most often, this is caused by exposure to irritants, such as cigarette smoke, air pollution, or industrial dust and chemicals.

Protecting Yourself and Others

Whether you're dealing with bronchitis or trying to avoid it, there are steps you can take to protect yourself and those around you:

• Practice Good Hygiene: Follow good hygiene practices like washing hands and using tissues to cover your mouth and nose when coughing or sneezing.
• Stay Informed: Knowing the difference between acute and chronic bronchitis can help you choose what's best for your health.
• Avoid Irritants: If you want to lower your risk of chronic bronchitis, stop smoking and avoid environmental irritants.
• Maintaining a healthy lifestyle: Exercise, balanced diet, hydration and sleep help support a strong immune system.
• Consult a Health Care Professional: If you suspect bronchitis or experience persistent symptoms, seek guidance from a health care provider, such as MedExpress. They can offer a proper diagnosis and recommend appropriate treatment. You can schedule an in-person visit at one of our centers, connect virtually with a provider right at home or just walk into any of our neighborhood medical centers at a time that works best for you.

Originally published December 2023. Updated August 2024.

References:

1 NIH. National Heart, Lung and Blood Institute. Bronchitis. Last updated on December 02, 2022. Accessed October 15, 2023.

2 National Library of Medicine. Acute bronchitis. Last updated February 2008 Feb. Accessed October 15, 2023.

3 CDC. Chest Cold (Acute Bronchitis) Basics. Last updated April 17, 2024. Accessed August 12, 2024.