What causes the dry coughing, extra mucus, and other cold symptoms you’ll suffer when you get a case of acute bronchitis??Bronchitis?is inflammation of the lining of your bronchial tubes, which are the airways that carry oxygen to and from your lungs. But it’s either a viral or bacterial infection that sets the wheels in motion that result in those symptoms.
“The majority of?acute bronchitis in kids?and adults is caused by a viral infection,” explains?Fernando Holguin, MD, professor of medicine of pulmonary sciences and critical care at the University of Colorado School of Medicine. Research suggests that majority is between 85 and 95 percent of all cases of acute bronchitis.?(1)
The illness typically improves in about 3 to 10 days and has no lasting effects, though a cough may linger for weeks after the infection has ended. But for people who have weaker immune systems, such as young children, the elderly, or those who have an illness like cancer or a health condition like as diabetes, there is a risk that acute bronchitis may develop into a more severe illness, such as pneumonia.
The rest of this article will focus on what causes acute bronchitis and how to prevent it. But it’s important to note that the other type of bronchitis,?chronic bronchitis, is a long-term, serious condition that, similar to acute bronchitis, is caused by inflamed bronchial tubes that produce a lot of mucus, making it difficult to breath.
The difference in chronic bronchitis is that the inflammation is caused by long-term exposure to industrial dust, fumes in the workplace, air pollution, secondhand smoke, other air pollutants, long-term uncontrolled asthma, or frequent childhood respiratory infections — and the inflammation is constant and does not go away.
When viruses or bacteria infect the already-inflamed bronchial tubes in people with chronic bronchitis, those individuals can experience periods when symptoms become even worse than usual. Early diagnosis and treatment, along with behavior changes (such as quitting smoking) can improve daily management of symptoms of chronic bronchitis, but the chance of the condition going away completely is low, especially for those who have severe cases.
But when it comes to acute bronchitis, if the same types of infections that cause the cold and flu — viral and bacterial ones — are to blame, why do some infections turn into acute bronchitis? Here’s what you need to know, and some tips for avoiding and warding off a case of acute bronchitis.
What Causes Acute Bronchitis
Yes, acute bronchitis is usually caused by the same viruses that cause colds and the flu. The infection typically begins in the nose, the sinuses, or the throat and spreads to the bronchial tubes, where it causes inflammation when the body tries to fight the infection, Dr. Holguin explains.
So is it possible to stop the flu or a cold from turning into bronchitis? Not necessarily,?says Carlos?Picone, MD, pulmonary section chief at Johns Hopkins–Sibley Memorial Hospital in Washington, DC.
It’s common for a cold or flu to be caused by an infection in the upper nasal respiratory epithelium, and there’s nothing you can do to prevent that infection from spreading into the lower airways (resulting in bronchitis), because those airways are so close to one another, Dr.?Picone?explains. “The two areas are very connected,” he says.
Viruses can be spread through physical contact, for instance if an infected person touches an object, like a light switch or an office coffee pot, and then an uninfected person touches that same object and then touches her eyes, mouth, or nose. They can also be spread via germ-laden droplets of moisture that spread through the air — as much as six feet away — when an infected person sneezes or coughs, according to the Centers for Disease Control and Prevention (CDC).?(2)
According to a study published in the journal Proceedings of the National Academy of Sciences, the flu virus can even be more easily spread than previously thought — just by breathing, without coughing or sneezing, especially during the first days of illness.?(3)
Exposure to irritants, like tobacco smoke, pollution, dust, and fumes, can cause or exacerbate acute bronchitis, too. And in less common cases, bacteria can lead to acute bronchitis.
Acute Bronchitis Symptoms May Be Annoying, but They’ll Help You Heal
Symptoms of acute bronchitis — coughing, a sore throat, and excess?mucus and phlegm?— may be irritating, but there’s a reason for them.?Coughing is the body’s way of clearing irritants out of your airways to prevent infection,?Holguin?explains. Though annoying, it will help stop the infection from getting worse, as well as get rid of irritants that are attacking your body in the first place. (4)
What about mucus and phlegm? When we’re healthy, mucus normally functions by trapping and preventing dust, bacteria, and other foreign invaders from entering the body. So, when we have an infection such as a cold (or a cold that causes bronchitis), the sinuses, mouth, throat, and lungs make extra mucus in an effort to expel more germs out of the body.
How to Avoid Getting Bronchitis
It’s not always possible to prevent acute bronchitis, particularly cases that can follow a viral infection like a cold, but you can take steps to minimize your risk. Here’s how:
- Wash your hands frequently and avoid touching your face to reduce your exposure to viruses and bacteria.?(5) The germs that cause colds, the flu, and other respiratory infections are highly contagious. The best way to reduce your risk of getting bronchitis is to avoid getting sick in the first place. Of course, when you are sick, take care not to spread the illness to other people. Stay at home, wash your hands frequently, and always cough or sneeze into your inner elbow.
- Avoid standing near people who are coming down with an illness or are visibly fighting cold or flu symptoms.
- Avoid cigarette smoke. Stop smoking, and be sure you are not exposed to?secondhand?smoke. (6)
- Get your annual flu shot.
- Consider wearing a mask. To protect your lungs, you may want to cover your mouth and nose when you work with paint, varnish, or other materials with strong fumes, or if you are going to be exposed to dust or in a large crowd.
- See your doctor to get the right diagnosis. There are a number of conditions that have symptoms that are similar to those of bronchitis, such as asthma and allergies. For example, “exposure to pollen can produce mucus, which can build up in lungs and be confused with acute bronchitis,” says?Holguin. “If you keep having bronchitis every change of season, you may want to see your doctor to see if you have an allergy.”
Editorial Sources and Fact-Checking
- Worrall?G. Acute Bronchitis.?Canadian Family Physician. February 2008.
- How Flu Spreads.?Centers for Disease Control and Prevention. September 20, 2022.
- Yan?J, Grantham M, Pantelic?J, et al. Infectious Virus in Exhaled Breath of Symptomatic Seasonal Influenza Cases From a College Community.?Proceedings of the National Academy of Sciences. January 18, 2018.
- Cough Culprits.?NIH News in Health. May 2017.
- Acute bronchitis: Is It contagious??Mayo Clinic. May 16, 2019.
- Bronchitis.?National Heart, Lung, and Blood Institute. March 24, 2022.