Macrolide- and Telithromycin-resistant Streptococcus pyogenes, Belgium, 1999–20031

We found a 13% macrolide resistance in 3,866 Streptococcus pyogenes isolated from tonsillopharyngitis patients; 59% macrolide-resistant isolates were distributed in 5 clones, suggesting the importance of both resistance gene transfer and clonal dissemination in the spread of these organisms. We also report one of the largest collections of telithromycin-resistant isolates