Clonal relationships among penicillin-susceptible, multiresistant serotype6B Streptococcus pneumoniae isolates recovered in Greece and France

In January 1996 the emergence of penicillin-susceptible, multiresistant ser otype 6B Streptococcus pneumoniae isolates resistant to chloramphenicol, te tracycline, erythromycin, clindamycin and trimethoprim-sulfamethoxazole was observed in young carriers in the city of Patras, located in the southwest ern region of Greece. Later, a significant spread of pneumococci with this unusual phenotype was noted in carriers living in various other areas of th e country. Using restriction fragment length polymorphism of the ribosomal RNA genes, clonal relationships were found between these Greek strains and sere type 6B penicillin-susceptible, multiresistant pneumococci isolated in France between January 1992 and September 1996. The French and Greek isola tes appear to have a common ancestry.