DIAGNOSIS OF INFLUENZA

Abstract

During the period from January, 1969, to December, 1972, 333 patients were admitted to Fairfield Hospital, in whom the presence of influenza infection was confirmed by isolation of the virus. The major clinical features observed In these patients are summarized in illustrative groups, to show the changing clinical spectrum of influenza in different age groups. The results of this study suggest the following conclusions: 1. The diagnosis of influenza on clinical grounds alone may be very difficult, particularly in the very young and the aged. 2. In children, influenza frequently presents as a severe, febrile, non-specific respiratory illness, or as croup. Children may also present with fever, convulsions, vomiting, Irritability and photophobia, the clinical picture suggesting a diagnosis of meningitis. Subclinical infection also appears to occur in the very young. 3. The characteristic clinical features of influenza are most commonly seen in adolescents and in young adults. 4. A clinical diagnosis of influenza may be overlooked in elderly patients, because the symptomatology is frequently overshadowed by lung complications. 5. The clinical spectrum of influenza in all age groups is wide, and in a small proportion the disease may present predominantly with fever alone or with fever and headache.