How Long Is Bronchitis Contagious?
Key takeaways:
Acute bronchitis is a lower respiratory tract infection that causes inflammation of the large airways.
People with acute bronchitis are most contagious for the first few days of their illness, although their cough might last longer.
Cough from bronchitis can continue even after you stop being contagious. You don’t have to wait for your cough to go away to return to work, school, or other activities.
Table of contents
The start of cold weather brings changing leaves, crisp air, and respiratory tract infections like the common cold, pneumonia, and bronchitis.
If you’re at home sick with bronchitis, you may wonder how likely it is you could make other people sick. Spoiler alert: Bronchitis is contagious, but just how likely you are to transmit it depends on the cause. Let’s take a look at how long you’re contagious with bronchitis and when it’s safe for you to get back to your regular routine.
What is bronchitis?
Bronchitis is a lower respiratory tract infection. It leads to inflammation of the large airways of the lungs — the bronchi.
This inflammation makes it more difficult to move air in and out of the lungs, and it causes symptoms like difficulty breathing, wheezing, and coughing.
Bronchitis can be chronic or acute:
Chronic bronchitis is a long-term condition caused by cigarette smoking or exposure to air pollution. This type of bronchitis is not contagious.
Acute bronchitis is a short-term condition, sometimes called a “chest cold.” This can last up to 3 weeks, and is often contagious — especially for the first few days.
Acute bronchitis can be caused by viruses, bacteria, or other causes. Of these, viruses are the most common cause. Viruses that cause bronchitis include:
Can the flu turn into bronchitis? Yes, the flu can go on to affect your lower respiratory tract and lead to bronchitis. Here’s what to watch for.
Self-care for bronchitis: There’s no cure for viral bronchitis, but these remedies can help you manage your symptoms.
COVID-19 vs. bronchitis: COVID and bronchitis share some symptoms. The best way to tell the difference is to get a COVID test.
Viral infections can trigger inflammation in the lungs, and inflammation causes a cough. Sometimes the inflammation and cough continue even after the viral infection is gone.
Quiz: Do I have bronchitis?
How long is acute bronchitis contagious?
How long bronchitis is contagious depends on what’s causing it. Let’s look at the most common causes of acute bronchitis.
Viral bronchitis
Acute bronchitis is most often caused by a virus. In general, people with this type of bronchitis are contagious for a few days to a week, although their symptoms might continue for longer. Exactly how long a person is contagious depends on which virus is causing the bronchitis and whether the person has any underlying health conditions.
“The exact time you’re contagious depends on the specific virus and the period of time you’re sick from the virus,” said Dr. Shiv Sudhakar, an infectious disease expert and GoodRx contributor. “In most cases, you’re usually contagious for a couple days to generally a week since this is usually the time it takes to recover from a viral illness.”
But Sudhakar cautions that people with weakened immune systems or underlying medical conditions may stay contagious for longer.
People with acute viral bronchitis are most contagious during the first several days of infection, when they feel their worst. But they can also be contagious for a few days before symptoms start. This means they can transmit the virus to others before they even realize they’re sick. Often, their cough will continue for a week or so even after the viral infection itself has faded.
Bacterial bronchitis
Bacteria can also cause acute bronchitis. In these cases, bronchitis stays contagious until it’s treated or the symptoms go away.
Sudhakar said that mycoplasma and pertussis (whooping cough) are two bacteria that cause bronchitis. “People with bacterial infections are considered infectious until they get appropriate treatment with antibiotics and their symptoms resolve. In some cases of pertussis, people can be infectious for as long as 3 weeks,” he said. Fortunately, these types of infections aren’t as common as viral bronchitis.
Irritant bronchitis
Sometimes acute bronchitis isn’t caused by an infection at all. Acute bronchitis can be triggered by breathing in smoke, dust, or fumes. In these cases, bronchitis isn’t contagious.
How is bronchitis spread?
The viruses that cause acute bronchitis spread through respiratory droplets. So you pick up these viruses the same way you pick up a common cold, the flu, or COVID.
A person who is sick with one of these viruses creates respiratory droplets that can spread the virus when they cough, sneeze, talk, or yell. If you come in contact with these droplets, you can get the virus and catch bronchitis, too. This can happen when you:
Touch surfaces contaminated with the virus
Spend time near a person with the infection
How can you prevent spreading bronchitis?
If you have acute bronchitis, there are several things you can do to prevent transmitting the infection to other people. Here’s how to minimize the spread:
Stay home while you’re feeling sick.
Cover your mouth when you cough or sneeze. Your hands touch a lot of surfaces, so covering your mouth with your elbow will make you less likely to spread germs.
Wash your hands frequently to avoid passing illness to other members of your household.
Most people start to feel better within a few days to a week. If you don’t have a fever and are feeling better, you can return to work, school, and other activities — even if you still have a lingering cough.
How long does bronchitis typically last?
Acute bronchitis lasts less than 3 weeks. This is different from chronic bronchitis, which is a type of chronic obstructive respiratory disease (COPD). Chronic bronchitis lasts for much longer. In fact, you can’t be diagnosed with chronic bronchitis until you’ve had a mucus-producing cough for at least 3 months.
Can bronchitis go away on its own?
Most of the time, acute bronchitis will go away on its own. This is most likely when the cause is a common cold virus. But bronchitis from the flu may benefit from antiviral medication, such as Tamiflu (oseltamivir). And bronchitis caused by SARS-CoV-2 may benefit from COVID treatment. Acute bronchitis caused by a bacterial infection also requires treatment with antibiotics.
Some people have a higher risk of having more severe illness from respiratory infections, including older adults and people with weakened immune systems. So it’s a good idea to see a healthcare professional if you suspect the flu, COVID, or bronchitis. Flu and COVID medications can shorten how long your symptoms last, but you’ll need to take them right away after your symptoms start.
How can you reduce the risk of catching bronchitis?
To reduce your chances of catching bronchitis, you can:
Stop smoking, or don’t start. And try to avoid secondhand smoke.
Get your yearly flu shot.
Consider getting the pneumonia vaccine if you’re eligible.
Try to avoid people who are sick, or you can wear a mask.
Frequently asked questions
Viral bronchitis is much more common than bacterial bronchitis. Bacteria cause fewer than 1 in 10 cases of acute bronchitis. A bacterial infection may be more likely if your symptoms are still getting worse after 7 to 10 days of illness, or they started to get better and then got worse again. A healthcare professional will take into account all of your symptoms to make a decision on how to best treat bronchitis.
Yes, bronchitis and pneumonia can cause serious illness and leave you feeling very sick. Some people will have only mild symptoms, but these can be life-threatening infections for others. People at increased risk include older adults, children, and those with other health conditions, such as heart or lung disease.
People with acute bronchitis often have a cough that lasts for weeks — even after the original infection is gone. You don’t need to wait until the cough disappears completely to return to your normal activities.
The bottom line
Bronchitis is a lower respiratory tract infection that causes airway inflammation. Viruses, bacteria, and smoke can all trigger acute bronchitis. Viral infections are the most common cause of acute bronchitis.
People with acute bronchitis from a virus are contagious for a few days up to a week. You’re most contagious in the first couple of days of illness, so it’s important to stay home when you first become sick. Bacterial bronchitis, and some types of viral bronchitis, can benefit from medical treatment. You can return to your normal activities once you no longer have a fever and your other symptoms are getting better.
Why trust our experts?
References
Agency for Healthcare Research and Quality. (n.d.). Acute bronchitis. U.S. Department of Health and Human Services.
American Lung Association. (n.d.). Chronic bronchitis.
Centers for Disease Control and Prevention. (2023). About Mycoplasma pneumoniae infection.
Centers for Disease Control and Prevention. (2023). Risk factors for pneumonia.
Centers for Disease Control and Prevention. (2024). Chest cold (acute bronchitis).
Centers for Disease Control and Prevention. (2024). Risk factors for severe illness from respiratory viruses.
Centers for Disease Control and Prevention. (2024). Types of COVID-19 treatment.
Clark, T. W., et al. (2014). Adults hospitalised with acute respiratory illness rarely have detectable bacteria in the absence of COPD or pneumonia; viral infection predominates in a large prospective UK sample. The Journal of Infection.
HealthDirect. (2022). Bronchitis.
National Heart, Lung, and Blood Institute. (2022). Bronchitis.
New South Wales Health. (2023). Respiratory viruses.
Singh, A., et al. (2024). Acute bronchitis. StatPearls.
