Epidemiology and management of penicillin-resistant pneumococci

Penicillin resistance in Streptococcus pneumoniae has spread continuously during the past 15 years, and is becoming a problem throughout the world. In many countries, a cryptic phase, when there are small increases in MIC, is followed by an emergence phase, and once a threshold of prevalence of resistance is crossed (about 8%), a rapid penetration phase tends to occur, that is possibly followed by an evolutive phase (increases in the more resistant strains) and finally by a stationary phase.