Influenza, hay fever and sinusitis: Know the differences

Influenza, hay fever and sinusitis are all very different upper respiratory tract syndromes that share very similar symptoms. “Flu” is caused by the influenza virus and usually presents with headaches, myalgia, fever and body aches. Hay fever is an allergic response of the body to a trigger, more often treated by removal of the trigger. There is no place for antibiotic usage in flu or hay fever; there is no clinical evidence to suggest that using antibiotics alters the course of the disease or prevents secondary infection. Treatment is mainly symptomatic and includes many over-the-counter medicines, antivirals and herbal treatments. On the other hand, sinusitis is a common inflammatory condition defined by persistent symptomatic inflammation of the sinonasal cavities lasting from less than four weeks to longer than three months. Either a virus or bacteria may cause sinusitis. Appropriate use of medical therapies, including antibiotics for sinusitis is necessary to optimise patient quality of life and daily functioning and minimise the risk of acute inflammatory exacerbations. Patients often present at the pharmacy with complaints of “flu”. However, in many instances, symptoms may be confused with those of an allergy or sinusitis. It is important to know and understand the difference between influenza and allergies such as hay fever and sinusitis, in order to ensure correct diagnosis and offer appropriate therapeutic approaches. This article will review the clinical manifestations of influenza, allergic rhinitis (hay fever) and sinusitis, and highlight the differences between these three illnesses.