Both the common cold and influenza are classified as upper respiratory infections, but they are caused by different viruses and affect the body in distinct ways. The flu, which is most often caused by influenza A and B viruses, tends to result in more severe symptoms that appear suddenly. The virus spreads through droplets from coughing or sneezing and can penetrate deeply into airway tissues, sometimes evading early detection by the immune system. This can lead to a strong inflammatory response once the infection is recognized.
In contrast, the common cold is usually triggered by rhinoviruses. Cold symptoms typically begin gradually and remain milder than those of the flu. Rhinoviruses generally stay in the upper airways and prompt a less intense immune response because the body recognizes them sooner. There are multiple types of rhinovirus, making it possible for someone to experience more than one cold in succession.
Treatment approaches differ for each illness. For colds, care focuses on symptom relief with over-the-counter medications, rest, and hydration. Mild cases of flu can be managed similarly, but severe symptoms may require antiviral medications prescribed by a doctor. These medications are most effective when started within two days of infection onset.
“If someone with the flu has worsening symptoms, including chest pain or high fever, they should seek immediate medical care.”
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