Incidence, predisposing factors and manifestations of invasiveHaemophilus influenzae infections in adults

Abstract
A retrospective study was conducted on invasiveHaemophilus influenzae infections in adults (⩾ 16 years) for the period 1971–1983 in two regions in Sweden. The annual incidence was determined to be 1.1 per 100,000. Predisposing factors included advanced age, bronchopulmonary diseases, alcoholism, traumatic head injury, malignant diseases and pregnancy. Pleuropulmonary infections were the most common manifestations followed by epiglottitis, meningitis and septicaemia of unknown origin. A death rate of 8 % was established. Both encapsulated and non-typable strains were found to be potentially pathogenic, but the non-typable strains had a lower virulence.