Penicillinase producing Neisseria gonorrhoeae in Zurich, Switzerland.

Of 1031 consecutive isolates of Neisseria gonorrhoeae examined before 31 July 1982, 30 strains showed beta-lactamase activity. All the penicillinase producing N gonorrhoeae (PPNG) strains were imported, 23 of them from South East Asia. One PPNG strain was identified as coming from Antigua and one from Chile, the first PPNG strains to be reported from these two countries. In 28 strains, the minimum inhibitory concentration (MIC) of penicillin was greater than or equal to 4.0 mg/l, and 15 strains were insensitive to tetracycline (MIC greater than or equal to 2.0 mg/l). Four strains were less sensitive to spectinomycin (MIC = 30 mg/l), while the remaining 26 were highly sensitive to this antibiotic. The African plasmid was found in only one strain (that originating from Antigua), and all other PPNG strains contained the Asian plasmid. Twenty PPNG strains contained the resistance plasmid together with the transfer plasmid. Auxotype determination showed that 18 PPNG strains were prototrophic whereas 11 were proline requiring.