Systemic infections due to type b Haemophilus influenzae. A retrospective study of 114 cases

: The choice of treatment, the importance of chemoprophylaxis in household contacts and the potential impact of immunization with vaccines against Haemophilus influenzae type b (Hib) currently under investigation are discussed on the basis of the patients hospitalized for invasive Hib infections at the University Children's Hospital Geneva from 1976 to 1985. Among 122 culture-proven infections due to Hib, there were 41% of cases of meningitis, 37.7% of epiglottitis, 9.8% of pneumonia, 5.7% of septicemia, 3.3% of cellulitis and 2.4% of septic arthritis. From 1981 to 1983, one strain of Hib produced beta-lactamase, but between 1984 and 1985, 5 strains (19.2%) produced beta-lactamase. Only one case of possible horizontal transmission of the infection was found in this 10-year period. We conclude that 1. the appearance of beta-lactamase producing strains of Hib requires that treatment be initiated with an antimicrobial agent resistant to beta-lactamase when a Hib infection is suspected; 2. in our region, only one case of an invasive Hib infection could theoretically have been prevented by chemoprophylaxis; and 3. the calculated theoretical impact of vaccination with the new types of vaccines against Hib could have prevented 106 of 122 cases of invasive Hib infections.