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Our study showed high macrolide resistance in Streptococcus pyogenes (S. pyogenes) in Chinese children with pharyngitis. The ermB gene code is the main resistance mechanism that leads to high level of resistance against macrolides in S. pyogenes. The ermB also is mainly responsible for Streptococcus pneumoniae (S. pneumoniae) in China. A total of 185 strains of S. pneumoniae were collected from the nasopharyngeal secretions of 0to 5-year-old children suffering from acute upper respiratory infections. Those strains with relatively high resistance to erythromycin (78.9%) and ermB and mefA were detected in all erythromycin-resistant strains, with ermB (þ) 79.5%, ermBþmefA (þ) 17.8%, and mefA (þ) 2.7%. Our other study showed that macrolides resistance in S. pneumoniae was very high from 87% to 94% from 2000 to 2005 (MIC> 256mg/ml). We had nine high-level resistant isolates that were negative for ermA, ermB, and mefA genes, which suggested that some other resistance mechanism exists, and some may be new, thus far unknown mechanism. Our further work will detect whole gene sequences of those nine isolates to find mutation mapping and sequencing that allowed the identification of the 23S rRNA alteration responsible for erythromycin resistance and others, from which we might find a new mechanism. Dr. Korppi mentioned that one study in Slovenia showed a strong correlation between the use of intermediate-acting macrolides and macrolide resistance of S. pyogenes and S. pneumoniae in children. However, the decline in total macrolide use was not paralleled by reduced macrolide resistance rates of S. pyogenes and S. pneumoniae during the 6-year period. Moreover, other study in Slovenia and Bergman’s study showed that total macrolide use and azithromycin use were associated with increased macrolide resistance. In the 1990s, the resistance rate of S. pyogenes to erythromycin was 43.3% in China. Second-generation macrolides (azithromycin and clarithromycin) were introduced into clinic use in 1995. Since then, second-generation macrolide use for initial therapy has increased greatly. Studies of multiple centers in Mainland China showed that the consumption of macrolides was more than half of the total DDD volume and the consumption of macrolides was always ranked the first (15.76–23.63 DDDs/100 patient-days) from 2000 to 2005. S. pneumoniae resistance increased from 87% to 94%. Our study showed that macrolide resistance of S. pyogenes was over 95% in 2008. China is now reducing the consumption of macrolides through government policy. Following those practices and noting the promising results of Finland, South Korea, Slovenia, and Japan, we will see the change in macrolide resistance rates of S. pyogenes, and S. pneumoniae in the next few years. As Dr. Korppi mentioned, during the period of decreased consumption of macrolides, pneumococcal penicillin resistance was only 3.6% in Finland. There was a study which showed that the total use of beta-lactam and the total use of cephalosporins were significantly connected to low-level penicillin resistance in S. pneumoniae. There was no statistically significant correlation between penicillin-nonsusceptible S. pneumoniae (PNSP) isolates and penicillin or total macrolide consumption. Samore et al. indicated that the use of different antimicrobials enhanced penicillin nonsusceptibility in S. pneumoniae through different mechanisms. Although both penicillin and cephalosporins of effects contribute to the dissemination of resistant S. pneumoniae strains, the latter effect is more powerful. One of our investigations showed similar results. Second-generation macrolides were commonly used for initial therapy not only for Chinese children with pharyngitis, but also for common colds and bronchitis mostly without etiologic examination. In fact, we have already observed antibiotic abuse in China as early as the 1990s. In pediatric outpatient departments, more than 98% of the patients who were diagnosed with common colds were given antibiotics by physicians. We agree that theoretically, there is no need to treat pharyngitis by macrolides. Because nearly all streptococcal strains are sensitive to penicillin and cephalosporins, the overuse of macrolides in the population may cause the development of macrolide resistance not only in S. pyogenes, but also in Mycoplasma pneumoniae. Macrolides cannot be used as the only drug in the treatment of community-acquired pneumonia (CAP) in children with atypical bacterial CAP cases mixed infections with pneumococcus or macrolide-