[Haemophilus influenzae infections in children less than 5 years of age in the community of Murcia during the 1992-1999 period].

BACKGROUND

Invasive disease due to Haemophilus influenzae has changed substantially since the introduction of the conjugated vaccine. This report studies the incidence and the clinical-epidemiological characteristics of invasive H. influenzae disease in children under five years of age during 1992-94 (before vaccination), 1995-97 (voluntary vaccination) and 1998-99 (obligatory vaccination).

PATIENTS AND METHODS

The study was performed by reviewing the clinical histories of 39 patients with H. influenzae isolates from sterile samples, according to microbiology data. The reference population's subgroup of the study, 40,322 children under 5, comprises 60% of the total in our community.

RESULTS

The overall incidence of invasive H. influenzae disease was 12.1/100,000 children under 5 and 15.7, 12.4 and 6.2 for the following periods respectively: before vaccination, during voluntary vaccination, and obligatory vaccination. All cases except one of them, were produced by H. influenzae type b and they were seen in children under 3. Meningitis accounted for more than half of the cases (51.3%). Fever was the most frequent sign (38 of 39 cases). Epiglottitis was the cause of the highest average hospital stay (20.8 days). All the patients were treated with cefotaxime, but half were also administered other antibiotics. Sequelae were seen in 7 cases, with no deaths.

CONCLUSIONS

The incidence of invasive H. influenzae disease was drastically reduced and no cases were seen in the last year. However, one vaccinated patient suffered a bacteremic etmoiditis. This case and the possibility of infection due to non-b serotypes requires ongoing surveillance for these infections.