Evolution of Streptococcus pneumoniae serotypes and antibiotic resistance in Belgium - update (1994-98)

Objective to from deep sites. To follow the evolution of capsular types and resistant of Streptococcus pneumoniae, isolated Methods More than 100 Belgian laboratories permanently collect S. pneumonia e strains isolated from puncture specimens (blood, cerebrospinal fluid, mid dle ear fluid, etc.) and forward them to the reference center in Leuven, in order to determine the capsular serogroups and types (SGTs) and their resi stance. Results From 1994 to 1998, the 5486 S. pneumoniae strains examined belonged to 39 of the 46 currently identified SGTs. The 10 most frequent SGTs accou nted for 78.9% of the isolates, and 97% of all isolates belonged to SGTs in cluded in the 23-valent vaccine. Overall mortality of patients with pneumoc occal bacteremia or meningitis was 9.7%, and 23.8% in patients over 80 year s. From 1994 to 1998, resistance to penicillin (P) increased from 7.6% to 1 4.2%, to tetracycline (T) from 14.9% to 28.0%, and to erythromycin (E) from 22.9% to 31%. Triple resistance (PTE) increased from 0.9% in 1994 to 6.6% in 1998. Five SGTs (6, 9, 14, 19 and 23) accounted for 50% of the isolates, but for > 90% of the penicillin-resistant or erythromycin-resistant isolat es. Conclusions Resistance of S. pneumoniae to penicillin, erythromycin and tet racycline is steadily increasing and is concentrated in five serotypes incl uded in the 23-valent pneumococcal vaccine. Increasing resistance and high mortality of invasive infections are an incentive to vaccinate vulnerable g roups.