Antibiotic susceptibilities, serotypes and auxotypes of Neisseria gonorrhoeae isolated in New Zealand.

OBJECTIVE

The aim of the study was to determine the distribution of auxotypes and serotypes and the prevalence of antibiotic resistance among New Zealand isolates of Neisseria gonorrhoeae.

MATERIALS AND METHODS

A total of 486 gonococci isolated in 1988 were auxotyped, serotyped, and tested for susceptibilities to ten antibiotics.

RESULTS

The gonococci were susceptible to all the antibiotics tested except penicillin and tetracycline. Eleven (2.2%) produced beta-lactamase, one (0.2%) showed chromosomal penicillin resistance, and 18 (3.7%) were resistant to a low-level of tetracycline. Most of the gonococci belonged to six auxotypes. The three predominant auxotypes were arginine-requiring (Arg-), non-requiring (NR), and arginine, hypoxanthine, uracil-requiring (AHU-). The majority of the isolates belonged to serogroup IB and to six serovars. The most prevalent serovars were IB-3 and IB-1. There was an association between penicillin susceptibility and auxotype or serovar among non-penicillinase producing N. gonorrhoeae (PPNG) isolates.

CONCLUSIONS

Antibiotic resistance, including penicillin resistance, remains uncommon among gonococci in New Zealand. Baselines have been established for future epidemiological studies using both auxotyping and serotyping.