Concurrent respiratory syncytial virus and influenza A infections in the institutionalized elderly and chronically ill.

During a community outbreak of respiratory syncytial virus and influenza A/Texas/77 infections, we investigated 71 cases of upper respiratory illness at a chronic disease hospital using a surveillance system plus viral and serologic studies. Of the 32 patients with an etiologic diagnosis, seven had respiratory syncytial virus, 24 had influenza, and one had dual infections with respiratory syncytial virus and influenza. No definite etiologic diagnosis was made in the remaining 39 patients. A comparison of the clinical features of patients infected with respiratory syncytial virus and influenza revealed no significant differences in the frequency of respiratory or constitutional signs and symptoms except for rhinorrhea, which was commoner in the respiratory syncytial virus group (P less than 0.05). Pneumonia developed in one patient with respiratory syncytial virus and in five patients with influenza. Our findings suggest that respiratory syncytial virus may be an important respiratory pathogen for the elderly and chronically ill, causing illness similar to influenza.