Evolution of Streptococcus pneumoniae Serotypes and Antibiotic Resistance in Spain: Update (1990 to 1996)

The surveillance in Spain of Streptococcus pneumoniae isolated in hospitals from different regions of the country was initiated in our laboratory in 1979. In that year we found that 6% of the pneumococci isolated from blood, cerebrospinal fluid (CSF), or lower respiratory tract (LRT) specimens were not penicillin susceptible and that these strains were distributed only among particular serogroups or serotypes (SGTs). We thus realized that although penicillin resistance was rare in most other countries, it was clearly significant in Spain (6). Rates of penicillin resistance increased continuously in the following years, reaching values up to 44.3% among invasive strains in 1989, and both highly penicillin-resistant and multidrug-resistant strains reached high levels (15.3 and 7.9%, respectively) (11). In the present decade, resistance to penicillin has spread throughout the world and numerous countries are observing the same pattern that occurred in our country during the 1980s (1, 2, 16). The situation with antimicrobial resistance in Spain at the end of the 1980s caused concern (3, 22), and knowledge of its evolution could be of interest for those countries where increasing resistance is being observed. This survey presents an update of the previous microbiological surveillance for pneumococcal infections. Here, we have included both invasive and noninvasive pneumococci isolated from 1990 to 1996 in Spanish hospitals. For comparative purposes, some tables and figures present data obtained in the period 1979 to 1989, including analysis of not only invasive strains (6, 11) but also noninvasive strains.