Diagnosis The distinction between different viral upper respiratory tract infections is loosely based on the location of symptoms with the common cold affecting primarily the nose, pharyngitis the throat, and bronchitis the lungs. However,there can be significant overlap and multiple areas can be affected. The common cold is frequently defined as nasal inflammation with varying amount of throat inflammation. Self-diagnosis is freqoent. Isolation if the actual viral agent involved is rarely performed, and it is generally not possible to identify the virus type through symptoms.