Sinusitis is inflammation of the paranasal sinuses, which may be due to infection, allergy, or autoimmune issues. Most cases are due to a viral infection and resolve over the course of 10 days. It is a common condition; for example, in the United States more than 24 million cases occur annually.
Read more about Sinusitis: Signs and Symptoms, Causes, Pathophysiology, Treatment, Epidemiology