SYMPTOM EXPRESSION IN NATURAL AND EXPERIMENTAL RHINOVIRUS COLDS

For the past 3 decades, rhinovirus grown in cell culture and used to i nduce experimental infections has been assumed to produce illness comp arable to natural rhinovirus illness. However, no studies have been co nducted to compare the characteristics of these two illnesses. We have used two data bases, one from natural colds of proven rhinovirus etio logy and one for experimental rhinovirus colds, to compare symptom occ urrence. The natural cold data set contained prospectively collected d ata for the frequency of occurrence of symptoms for 139 insurance empl oyees with natural rhinovirus colds. The experimental colds data base was obtained from 10 separate volunteer studies involving a total of 1 25 subjects who had a rhinovirus inoculation into the nose. Daily symp tom frequency for the natural and experimental illnesses found that th e symptoms of nasal obstruction and malaise occurred significantly mor e often on illness days 1-5 during experimental colds. Also, significa nt differences were found for days 1-4 for feverishness/fever days 1-3 for nasal discharge, days 1-2 for sneezing, days 3-5 for sore throat, and day 1 for cough. Some of the latter symptoms occurred more freque ntly with experimental and some with natural infection. In general, th e illnesses associated with the two types of infection were more simil ar than they were different.