Cough Reflex Test (CRT) Practice

A persistent cough accompanied by clear sputum is commonly associated with a viral infection. In many cases, such infections lead to an upper respiratory tract response, which can manifest as a cough that persists as the body attempts to clear mucus and irritants from the airways. The presence of clear sputum typically suggests that there is no significant bacterial infection, which would more likely produce yellow or green colored sputum due to the presence of inflammatory cells.

While other conditions may involve coughing, they often present with different characteristics of sputum or other clinical signs. For instance, chronic obstructive pulmonary disease (COPD) exacerbations usually involve more productive coughs with colored sputum and may have other symptoms such as wheezing and shortness of breath. Chronic fungal infections tend to present with more complex symptoms and can cause different types of sputum based on the type of fungus. An error in blood circulation does not typically lead to cough or sputum production as primary symptoms.

Thus, a viral infection is the most fitting explanation for the symptoms described, as it aligns closely with the typical clinical presentation of cough and clear sputum.