Clonal spread of group A streptococcus with the new type of erythromycin resistance. Finnish Study Group for Antimicrobial Resistance.
In 1990, a new type of erythromycin resistance phenotype, designated NR, was found in group A streptococcus (GAS) in Finland. In the present study, the distribution of GAS isolates with this and other erythromycin-resistance phenotypes was surveyed in Finland, and the clonality of the isolates was explored. Of 4179 GAS isolates collected from all over Finland, 695 (17%) were resistant to erythromycin, and 82% of these had the NR phenotype. Of a group of 96 isolates with the NR phenotype from different areas, 91% was T4 serotype, opacity factor-positive. The majority of these isolates were studied further: All were M4 serotype and 88% were of one clonal origin in genetic analyses. Thus, one single clone predominates among erythromycin-resistant GAS in Finland. This clone is of T4M4 serotype and mediates the new type of erythromycin resistance, characterized by the NR phenotype.
Kataja
J
J
Antimicrobial Research Laboratory, National Public Health Institute, Turku, Finland. jankat@utu.fi
Huovinen
P
P
Muotiala
A
A
Vuopio-Varkila
J
J
Efstratiou
A
A
Hallas
G
G
Seppälä
H
H
D015373:Bacterial Typing Techniques; D004352:Drug Resistance, Microbial; D004917:Erythromycin / Q000494:pharmacology*; D005387:Finland / Q000453:epidemiology; D005838:Genotype; D005843:Geography; D006801:Humans; D010641:Phenotype; D019105:Random Amplified Polymorphic DNA Technique; D012703:Serotyping; D013290:Streptococcal Infections / Q000453:epidemiology*; D013297:Streptococcus pyogenes / Q000145:classification / Q000187:drug effects*
D004917:Erythromycin