Characterisation of macrolide-non-susceptible Streptococcus pneumoniae colonising children attending day-care centres in Athens, Greece during 2000 and 2003.
Nasopharyngeal Streptococcus pneumoniae isolates colonising young children are representative of isolates causing clinical disease. This study determined the frequency of macrolide-non-susceptible pneumococci, as well as their phenotypic and genotypic characteristics, among pneumococci collected during two cross-sectional surveillance studies of the nasopharynx of 2847 children attending day-care centres in the Athens metropolitan area during 2000 and 2003. In total, 227 macrolide-non-susceptible pneumococcal isolates were studied. Increases in macrolide non-susceptibility, from 23% to 30.3% (p <0.05), and in macrolide and penicillin co-resistance, from 3.4% to 48.6% (p <0.001), were identified during the study period. The M resistance phenotype, associated with the presence of the mef(A)/(E) gene, predominated in both surveys, and isolates carrying both mef(A)/(E) and erm(AM) were identified, for the first time in Greece, among the isolates from the 2003 survey. Pulsed-field gel electrophoresis analysis of the isolates from the 2000 survey indicated the spread of a macrolide- and penicillin-resistant clone among day-care centres. The serogroups identified most commonly in the study were 19F, 6A, 6B, 14 and 23F, suggesting that the theoretical protection of the seven-valent conjugate vaccine against macrolide-non-susceptible isolates was c. 85% during both study periods.
Souli
M
M
Fourth Department of Internal Medicine, Athens University School of Medicine, University General Hospital Attikon, Chaidari, Greece.
Volonakis
K
K
Kapaskelis
A
A
Galani
I
I
Grammelis
V
V
Vorou
R
R
Tsivra
M
M
Chryssouli
Z
Z
Katsala
D
D
Giamarellou
H
H
D001426:Bacterial Proteins / Q000235:genetics; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D002656:Child Day Care Centers; D002675:Child, Preschool; D024881:Drug Resistance, Bacterial / Q000235:genetics; D006115:Greece / Q000453:epidemiology; D006801:Humans; D007223:Infant; D018942:Macrolides / Q000494:pharmacology*; D008565:Membrane Proteins / Q000235:genetics; D008780:Methyltransferases / Q000235:genetics; D008826:Microbial Sensitivity Tests; D009305:Nasopharynx / Q000382:microbiology; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D018571:Sentinel Surveillance; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification; D014505:Urban Population
D001426:Bacterial Proteins; D018942:Macrolides; C117866:MefA protein, Streptococcus; D008565:Membrane Proteins; D008780:Methyltransferases; C035181:rRNA (adenosine-O-2'-)methyltransferase