title: Antimicrobial susceptibilities and serotypes of invasive Streptococcus pneumoniae strains in Switzerland.
abstract: In 1993 and 1994, 10 microbiological laboratories in Switzerland collected 351 strains of Streptococcus pneumoniae from invasive infections. Susceptibilities to the main representatives of the chemical classes were as follows: penicillin, 93%; chloramphenicol, 92%; erythromycin, 94%; sulfamethoxazole-trimethoprim, 86%; tetracycline, 92%; vancomycin, 100%. Forty-three strains showed resistance to one agent, and 35 strains showed resistance to two or more antimicrobial agents simultaneously; i.e., 22% of the strains were resistant to at least one antimicrobial agent. Four strains (1%) were fully resistant to penicillin, whereas 21 strains (6%) showed reduced susceptibility. Of these 25 strains not fully susceptible to penicillin, 10 were resistant to one, 3 were resistant to two, and 8 were resistant to three additional antimicrobial agents. Of the quinolones, sparfloxacin was the most active substance, with an MIC at which 90% of the strains are inhibited of 0.5 mg/liter. The most common serotypes were types 6 (13.6% of isolates), 7 (10.5%), 19 (10.5%), 14 (9.1%), and 1 (8.5%) as well as 3 and 23 (8.0% each). Reduced susceptibility to penicillin was found mainly among serotypes 6, 14, 19, and 23. The currently available 23-valent pneumococcal vaccine covers 320 (91%) of the pneumococci isolated. Regional differences within Switzerland with regard to serotypes and antimicrobial resistance were not observed.
authors.affiliation: Department of Medical Microbiology, University of Zürich, Switzerland.
authors.forename: J
authors.initials: J
authors.lastname: Wüst
authors.forename: E
authors.initials: E
authors.lastname: Huf
authors.forename: F H
authors.initials: FH
authors.lastname: Kayser
mesh_terms: D001428:Bacterial Vaccines / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D018432:Drug Resistance, Multiple; D006801:Humans; D010403:Penicillin Resistance; D011008:Pneumococcal Infections / Q000188:drug therapy / Q000382:microbiology / Q000517:prevention & control; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification* / Q000187:drug effects* / Q000302:isolation & purification; D013557:Switzerland
chemical_list: D001428:Bacterial Vaccines