Influenza, commonly known as the flu, is a respiratory infection caused by influenza viruses that primarily affect the nose, throat, and sometimes the lungs. It is a contagious illness that can range from mild to severe, and in some instances, can lead to serious complications. Asthma is a chronic respiratory condition characterized by inflammation and narrowing of the airways, which can lead to symptoms such as wheezing, shortness of breath, chest tightness, and coughing. This condition can affect individuals of all ages and often begins during childhood.
Understanding the Relationship Between Flu and Asthma
The flu does not cause new-onset asthma in most adults. The flu is a viral infection that can worsen existing asthma symptoms. For individuals who already have asthma, the flu is a significant trigger for exacerbations, often leading to more severe symptoms compared to the general population. People with asthma are at a higher risk for developing complications from the flu, such as pneumonia, which can be serious.
While the flu generally does not cause adult-onset asthma, severe respiratory infections, including those caused by influenza viruses, in early childhood can increase the risk of developing asthma later in life. This connection suggests that early life viral infections can contribute to airway susceptibility, especially if there is a genetic predisposition. However, this is distinct from the flu directly causing asthma as an immediate consequence in adults.
Biological Mechanisms of Flu-Induced Asthma Exacerbations
When the influenza virus infects the respiratory system, it causes irritation and inflammation in the lungs. This viral infection can lead to increased mucus production and further narrowing of the airways in individuals with asthma. These changes can significantly worsen asthma symptoms like wheezing, chest tightness, and shortness of breath. The inflammation can also increase airway hyperresponsiveness, making asthmatic airways more sensitive to other triggers.
The immune system’s response to the flu virus can also intensify underlying asthmatic inflammation. In asthmatic individuals, this response can contribute to airway swelling and constriction. This heightened inflammatory state makes it harder for individuals with asthma to breathe effectively during a flu infection. The combined effects of viral irritation and exacerbated immune responses contribute to the increased severity of flu in asthmatics.
Protecting Against Flu’s Impact on Asthma
An annual flu vaccine is a primary protective measure for individuals with asthma. The flu vaccine helps the body develop antibodies to fight off the infection and can reduce the risk of severe illness and complications, including asthma attacks. Most people with asthma, including children over 6 months of age, should receive the injectable flu vaccine rather than the nasal spray, which is generally not recommended for asthmatics.
Good hygiene practices are also important for preventing flu transmission. Regularly washing hands with soap and water, avoiding touching the face, and staying away from sick individuals can help reduce exposure to the virus. Adhering to prescribed asthma medications, such as controller inhalers, is important even when feeling well, as this helps maintain controlled asthma and reduces the risk of severe flare-ups if the flu is contracted. If an asthmatic person contracts the flu, monitoring symptoms, using rescue inhalers as needed, and seeking medical attention for worsening symptoms, such as severe breathing trouble or persistent cough, are important steps.