When no complications occur, symptoms normally resolve in 4 to 10 days. Diagnosis Clinical symptoms and signs are nonspecific. Bacterial infections, allergic rhinorrhea, and other disorders also cause upper respiratory tract symptoms and at onset, they may be confused with primary coryza. Differentiation depends on the season and the course of the symptoms. Fever and more severe symptoms usually differentiate infuenza.
Substantial leukocytosis indicates a disorder other than an uncomplicated common cold.
The Common Cold Immunity is virus type-specific. Effective experimental vaccines have been prepared for single types of rhino- and paramyxoviruses, but as the numerous types and strains of known viruses have precluded production of a useful vaccine, except for influenza viruses. Handwashing and perhaps use of a disinfectant may be beneficial in an infectious household, where most viral respiratory infections are spread. A warm, comfortable environment and measures to prevent direct spread of infection are recommended for all persons. Antipyretics and analgesics are commonly used.