Characterisation of invasive pneumococcal isolates in Catalan children up to 5 years of age, 1989-2000.

Ninety-six Streptococcus pneumoniae strains isolated between January 1989 and December 2000 from usually sterile sites of children aged < 5 years of age were included in the study. Resistance to penicillin (38.6% intermediate, 10.4% high-level), cefotaxime (20.8%), tetracycline (41.7%), chloramphenicol (33.3%) and erythromycin (27.1%), as well as serogroup/type, were related to age and pathology. Strains from children aged < 2 years showed the highest penicillin resistance rate. Resistance to penicillin, tetracycline, chloramphenicol and erythromycin was the most common pattern (18.8% of strains). Most isolates (80.2%) belonged to serogroups/types included in the heptavalent conjugate vaccine.