Bronchiolitis is a common illness of the respiratory tract caused by an infection that affects the tiny airways, called the bronchioles, that lead to the lungs. As these airways become inflamed, they swell and fill with mucus, which can make breathing difficult.
Childcare attendance and exposure to cigarette smoke also can increase the likelihood that an infant will develop bronchiolitis.
Although it's often a mild illness, some infants are at risk for a more severe disease that requires hospitalization. Conditions that increase the risk of severe bronchiolitis include prematurity, prior chronic heart or lung disease, and a weakened immune system due to illness or medications.
Kids who have had bronchiolitis may be more likely to develop asthma later in life, but it's unclear whether the illness causes or triggers asthma, or whether children who eventually develop asthma were simply more prone to developing bronchiolitis as infants. Studies are being done to clarify the relationship between bronchiolitis and the later development of asthma.
Bronchiolitis is usually caused by a viral infection, most commonly respiratory syncytial virus (RSV). RSV infections are responsible for more than half of all cases of bronchiolitis and are most widespread in the winter and early spring. Other viruses associated with bronchiolitis include rhinovirus, influenza (flu), and human metapneumovirus.
The first symptoms of bronchiolitis are usually the same as those of a common cold:
These symptoms last a day or two and are followed by worsening of the cough and wheezing (high-pitched whistling noises when exhaling).
Sometimes more severe respiratory difficulties gradually develop; signs include:
Sometimes these symptoms can lead to dehydration. Less commonly, babies (especially those born prematurely) may have episodes where they briefly stop breathing (called apnea) before developing other symptoms.
In severe cases, symptoms may worsen quickly. A child with severe bronchiolitis may get fatigued from the work of breathing and have poor air movement in and out of the lungs due to the clogging of the small airways. The skin can turn blue (called cyanosis), which is especially noticeable in the lips and fingernails.
The infections that cause bronchiolitis are contagious. The germs can spread in tiny drops of fluid from an infected person's nose and mouth, which may become airborne via sneezes, coughs, or laughs, and also can end up on things the person has touched, such as used tissues or toys.
Infants in childcare centers have a higher risk of contracting an infection that may lead to bronchiolitis because they're in close contact with lots of other young children.
The best way to prevent the spread of viruses that can cause bronchiolitis is frequent hand washing. It may help to keep infants away from others who have colds or coughs. Babies who are exposed to cigarette smoke are more likely to develop severe bronchiolitis compared with those from smoke-free homes. So it's important to protect children from secondhand smoke.
There's no bronchiolitis vaccine available yet, but a medication can be given to lessen the severity of the disease. It's recommended only for infants at high risk of severe disease, such as those born very prematurely or those with chronic lung or heart disease. The medication, which contains antibodies to RSV, is given as an injection monthly during peak RSV season.
The incubation period (the time between infection and the onset of symptoms) ranges from several days to a week, depending on the infection causing the bronchiolitis.
Cases of bronchiolitis usually last about 12 days, but kids with severe cases can cough for weeks. The illness generally reaches its peak on the second or third day after coughing begins, causing breathing difficulty before gradually resolving.
Fortunately, most cases of bronchiolitis are mild and require no specific professional treatment. Antibiotics aren't useful because bronchiolitis is caused by a viral infection, and antibiotics are only effective against bacterial infections. Medication may sometimes be given to help open a child's airways.
Infants who have trouble breathing, are dehydrated, or appear fatigued should be evaluated by a doctor. Those who are moderately or severely ill may need to be hospitalized, watched closely, and given fluids and humidified oxygen. Rarely, in very severe cases, some babies are placed on respirators to help them breathe until they start to get better.
The best treatment for most kids is time to recover and plenty of fluids. Making sure a child drinks enough fluids can be tricky, though, because infants with bronchiolitis may not feel like drinking. They should be offered fluids in small amounts at more frequent intervals than usual.
Indoor air, especially during winter, can dry out airways and make the mucus stickier. Some parents use a cool-mist vaporizer or humidifier in the child's room to help loosen mucus in the airway and relieve cough and congestion. If you use one, clean it daily with household bleach to prevent mold build-up. Avoid hot-water and steam humidifiers, which can be hazardous and can cause scalding.
To clear nasal congestion, try a bulb syringe and saline (saltwater) nose drops. This can be especially helpful just before feeding and sleeping. Sometimes, keeping a child in a slightly upright position may help ease labored breathing.
Acetaminophen can be given to reduce fever and make your child more comfortable. Be sure to follow the appropriate dosage information based on your child's weight.
Call your doctor if your child:
Seek immediate help if you feel your child is having difficulty breathing and the cough, retractions, or wheezing are getting worse, or if his or her lips or fingernails appear blue.
Reviewed by: Mary L. Gavin, MD
Date reviewed: January 2014
|Centers for Disease Control and Prevention (CDC) The mission of the CDC is to promote health and quality of life by preventing and controlling disease, injury, and disability. Call: (800) CDC-INFO|
|Lungs and Respiratory System By the time we're 70 years old, we will have taken at least 600 million breaths. All of this breathing couldn't happen without the respiratory system.|
|Pneumonia Pneumonia is a common infection of the lungs that can usually be treated without a hospital stay.|
|Lungs and Respiratory System Each day you breathe about 20,000 times. Find out more about the lungs and breathing process.|
|Respiratory Syncytial Virus Respiratory syncytial virus (RSV) is a major cause of respiratory illness in young children. Learn how to recognize the signs and symptoms of this contagious infection.|
|Common Cold With kids getting up to eight colds a year, this contagious viral infection is the most common infectious disease in the United States and the top reason kids visit the doctor and miss school.|
|Flu Facts Every year from October to May, millions of people across the United States come down with the flu. Get the facts on the flu - including how to avoid it.|
|Adenovirus Adenoviruses account for about 10% of acute respiratory infections in kids and are a frequent cause of diarrhea.|
|Coping With Colds Most teens get between two and four colds each year. Read this article for the facts on chicken soup, cold medicines, and other ways to feel better.|
|Movie: Lungs & Respiratory System Watch this movie about the respiratory system, the system that enables you to breathe.|
|Chilling Out With Colds Cough, sneeze, snort. Those are the sounds of a cold. Find out more about colds in this article for kids.|
|Influenza (Flu) Flu symptoms tend to develop quickly and are usually more severe than the typical sneezing and stuffiness of a cold. Yearly vaccination is the best protection against the flu.|
|Flu The flu is a virus that can make you sick for a week or longer. Find out more in this article for kids.|
|Coughing Coughs are a frequent symptom of childhood illness, but don't usually signify a serious condition. Learn about different coughs and how to help.|
What to expect when coming to Akron Children's
For healthcare providers and nurses
Residency & Fellowships, Medical Students, Nursing and Allied Health
For prospective employees and career-seekers
Our online community that provides inspirational stories and helpful information.