Hay fever, or allergic rhinitis, is a common condition with symptoms similar to those of a cold. There may be sneezing, congestion, runny nose, and sinus pressure.
It is caused by an allergic response to airborne substances, such as pollen. The time of year it happens depends on what substance, or allergen, the person reacts to.
Despite its name, hay fever does not mean that the person is allergic to hay and has a fever. Hay is hardly ever an allergen, and fever is not a symptom.