Viral asthma describes a respiratory condition where viral infections trigger asthma symptoms, such as wheezing and coughing. This form of asthma is particularly common in children, though it can affect adults as well. Understanding whether these episodes are temporary or indicate a long-term condition is a common concern for many.
Viral-Induced Wheeze Versus Asthma
Viral-induced wheeze occurs when a cold virus irritates their airways, causing them to swell and narrow. Children with viral-induced wheeze are typically well and symptom-free between episodes, and the wheezing usually resolves by the time they reach school age. Approximately one-third of all children experience viral-induced wheeze.
Asthma, in contrast, is a chronic inflammatory condition of the airways that can cause symptoms even when a person does not have a viral infection. While viral infections can trigger asthma attacks, individuals with asthma may also experience symptoms due to other triggers like exercise, allergens, or pollutants. Some children with viral-induced wheeze may later develop asthma, but many do not. Children are more likely to develop asthma if they have a family history of asthma, eczema, or hay fever.
How Viral Asthma Progresses Over Time
For many children, viral asthma is a temporary condition, with symptoms often disappearing by kindergarten. A small percentage may still develop chronic asthma later. Severe bronchiolitis, a viral lung infection common in young children, can be a risk factor for developing childhood asthma.
In adults, viral-induced asthma often represents an exacerbation of pre-existing asthma. However, a viral infection can also trigger adult-onset asthma in individuals who have not previously experienced symptoms, or cause a recurrence in those who had asthma as children but been symptom-free for years. Individual viral asthma attacks can vary in duration, lasting anywhere from a few days to several weeks. Symptoms may gradually increase over 7 to 10 days before becoming fully noticeable.
Identifying Symptoms and Common Triggers
The symptoms of viral asthma are similar to those caused by other asthma triggers, including wheezing, coughing, shortness of breath, and chest tightness. When associated with a viral infection, additional symptoms such as a stuffy or runny nose, fever, chills, headache, sneezing, and fatigue may also be present. Respiratory viruses are frequent triggers for asthma flare-ups in both children and adults. Rhinovirus, which causes the common cold, is a common culprit, accounting for a significant percentage of asthma exacerbations. Other viruses known to trigger viral asthma include Respiratory Syncytial Virus (RSV), influenza (flu), parainfluenza, adenoviruses, bocavirus, and human metapneumovirus.
Managing and Preventing Viral Asthma Episodes
Managing viral asthma involves both quick-relief treatments for acute attacks and long-term control medications to prevent future episodes. Quick-relief medications, such as short-acting beta-agonists (SABAs) like albuterol, are bronchodilators that relax the muscles around the airways for immediate relief.
For long-term control, inhaled corticosteroids (ICS) are frequently prescribed to reduce inflammation in the airways. Examples include fluticasone, budesonide, and mometasone. Sometimes, a combination of an inhaled corticosteroid and a long-acting beta-agonist (LABA) may be used in a single inhaler for better symptom control and to reduce exacerbations.
Preventing viral asthma episodes largely focuses on reducing exposure to respiratory infections. This includes:
Practicing frequent and thorough hand washing.
Avoiding close contact with individuals who are sick.
Regularly cleaning and disinfecting frequently touched surfaces.
Staying up-to-date on recommended vaccinations, such as the flu vaccine, can also help reduce the risk of viral infections that trigger asthma.