However, in evaluating the patient who calls you on the telephone or presents to the office, you must efficiently and accurately be able to differentiate trivial from serious and potentially treatable infections. These questions and others should give you clues to create a differential diagnosis. Peak incidence is from early fall until spring, although colds are seen throughout the year. Headache, mild conjunctivitis, hoarseness and cough may also be seen.
High fever is uncommon in the adult.
While two to three percent of colds may be complicated by secondary bacterial infection, including sinusitis and otitis media, these are usually evidenced by additional findings in the history and physical exam and are rarely subtle. There is seasonal variation in infection rates of the different viruses, but all produce the same general syndrome. The flu syndrome is a severe illness, lasting from three days to two weeks with convalescence over one to four weeks. Complications include prolonged airway hyperreactivity, particularly in patients with asthma and chronic bronchitis. Secondary bacterial bronchitis and pneumonia are seen in up to ten percent of patients, and usually present as purulent or bloody sputum and increased fever after a few days of apparent clinical improvement.