Introduction and clonal spread of penicillin- and trimethoprim/sulfamethoxazole-resistant Streptococcus pneumoniae, serotype 9V, in southern Sweden.
As part of an intervention project, all patients in Malmöhus county with a culture positive for penicillin-resistant pneumococci, MIC > or =0.5 mg/L (PRP), have been registered since January 1995. Nasopharyngeal specimens were obtained from family members and close contacts of identified carriers. Children were denied attendance at regular day-care until PRP-negative. In 1995 and 1996, PRP were isolated from 882 individuals, 364 of whom had clinical infection and the remaining of whom were asymptomatic carriers. In 49%, the PRP were of serogroup 9, with MIC of penicillin 0.5-2.0 mg/L and resistance to trimethoprim/sulfamethoxazole. Further analyses with serotyping and genetic fingerprinting suggested strongly that most of the isolates belonged to a single serotype 9V clone. Month by month, an apparently continuous spread appeared from one municipality to a neighboring one. In most communities, the serotype 9V PRP appeared and disappeared within a few months. The active procedures of the intervention project may have limited the spread of the clone in the county.
Melander
E
E
Department of Community Medicine, Lund University, Malmö, Sweden.
Ekdahl
K
K
Hansson
H B
HB
Kamme
C
C
Laurell
M
M
Nilsson
P
P
Persson
K
K
Söderström
M
M
Mölstad
S
S
D002648:Child; D002656:Child Day Care Centers; D002675:Child, Preschool; D016358:Contact Tracing; D016172:DNA Fingerprinting; D018432:Drug Resistance, Multiple; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control / Q000635:transmission*; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D013548:Sweden / Q000453:epidemiology; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000494:pharmacology*
D010406:Penicillins; D015662:Trimethoprim, Sulfamethoxazole Drug Combination