[Clinical and epidemiological characteristics of respiratory virus infections among adults hospitalized during 2004 influenza season].

BACKGROUND During yearly influenza (FLU) season, FLU viruses are well represented among hospitalized patients as in the community. Also, other respiratory viruses could be represented among adult in-patients. AIM to describe the presence and clinical- epidemiological characteristics of non-FLU respiratory virus infections (respiratory syncytial-RSV, parainfluenza and adenovirus-ADV) among hospitalized adults during FLU season and to compare with FLU-A (IA) or -B (IB) cases. PATIENTS AND METHODS Adult patients hospitalized at Hospital Clínico Universidad Católica between May to July 2004 with a respiratory virus infections confirmed by rapid antigen test or direct immunofluorescence of IA, IB (Flu group) or RSV, parainfluenza (1-2-3) and ADV (non-Flu group) were included. RESULTS 86 cases were identified: 73.5% FLU (48.2% IA, 25.3% IB) and 26.5% non-FLU (15.7% parainfluenza-2; 8.4% RSV; 1.2% parainfluenza-3; 1.2% ADV). No differences were observed in general characteristics and evolution of patients. In FLU-group were more frequently observed myalgia, cough, hospitalization due to febrile syndrome, higher values of C-reactive protein and band leukocytes count (p < 0.05). CONCLUSIONS During 2004 FLU season a 26.5 % of respiratory viral infection were due to non-FLU viruses among adult hospitalized in our centre. The difficulty to difference FLU vs. non-FLU infections, suggest that it is necessary to include other respiratory virus in the viral etiological diagnosis, even in FLU season.