Abstract
In 1982 an increase of penicillinase producing strains of Neisseria gonorrhoeae (PPNG), carrying the 4.5 megadalton Asian type plasmid and the 24 megadalton transfer plasmid (Asia+), was observed in Amsterdam. The main auxotypes were proline requiring (Pro-) and proline and hypoxanthine requiring (Pro-Hyx-). Using two monoclonal antibody systems, it was shown that the serovars of strains with these auxotypes isolated in 1981 were different from those isolated in 1982, which indicated the start and end of microepidemics. Different serovars were also observed in Pro- and non-requiring (NR) Asia- PPNG strains isolated in 1981-2 and 1985 respectively. Only one serovar (Aedih/Arst) was common in strains isolated in 1981-2 as well as in 1985.