Recently, the first Neisseria gonorrhoeae strain (H041) that is highly resistant to the extended-spectrum cephalosporin (ESC) ceftriaxone, the last remaining option for empirical first-line treatment, was isolated. We performed a detailed characterization of H041, phenotypically and genetically, to confirm the finding, examine its antimicrobial resistance (AMR), and elucidate the resistance mechanisms. H041 was examined using seven species-confirmatory tests, antibiograms (30 antimicrobials), porB sequencing, N. gonorrhoeae multiantigen sequence typing (NG-MAST), multilocus sequence typing (MLST), and sequencing of ESC resistance determinants (penA, mtrR, penB, ponA, and pilQ). Transformation, using appropriate recipient strains, was performed to confirm the ESC resistance determinants. H041 was assigned to serovar Bpyust, MLST sequence type (ST) ST7363, and the new NG-MAST ST4220. H041 proved highly resistant to ceftriaxone (2 to 4 g/ml, which is 4-to 8-fold higher than any previously described isolate) and all other cephalosporins, as well as most other antimicrobials tested. A new penA mosaic allele caused the ceftriaxone resistance. In conclusion, N. gonorrhoeae has now shown its ability to also develop ceftriaxone resistance. Although the biological fitness of ceftriaxone resistance in N. gonorrhoeae remains unknown, N. gonorrhoeae may soon become a true superbug, causing untreatable gonorrhea. A reduction in the global gonorrhea burden by enhanced disease control activities, combined with wider strategies for general AMR control and enhanced understanding of the mechanisms of emergence and spread of AMR, which need to be monitored globally, and public health response plans for global (and national) perspectives are important. Ultimately, the development of new drugs for efficacious gonorrhea treatment is necessary.

Neisseria gonorrhoeae is a major public health problem globally, especially because the bacterium has developed resistance to most antimicrobials introduced for first-line treatment of gonorrhea. In the present study, 96 N. gonorrhoeae isolates with highlevel resistance to penicillin from 121 clinical isolates in Thailand were examined to investigate changes related to their plasmidmediated penicillin resistance and their molecular epidemiological relationships. A ␤-lactamase (TEM) gene variant, bla , that may be a precursor in the transitional stage of a traditional bla TEM-1 gene into an extended-spectrum ␤-lactamase (ESBL), possibly causing high resistance to all extended-spectrum cephalosporins in N. gonorrhoeae, was identified. Clonal analysis using multilocus sequence typing (MLST) and N. gonorrhoeae multiantigen sequence typing (NG-MAST) revealed the existence of a sexual network among patients from Japan and Thailand. Molecular analysis of the bla TEM-135 gene showed that the emergence of this allele might not be a rare genetic event and that the allele has evolved in different plasmid backgrounds, which results possibly indicate that it is selected due to antimicrobial pressure. The presence of the bla TEM-135 allele in the penicillinaseproducing N. gonorrhoeae population may call for monitoring for the possible emergence of ESBL-producing N. gonorrhoeae in the future. This study identified a bla TEM variant (bla TEM-135 ) that is a possible intermediate precursor for an ESBL, which warrants international awareness. N eisseria gonorrhoeae is the causative agent of gonorrhea, which is the second most prevalent bacterial sexually transmitted infection globally. During recent decades, N. gonorrhoeae has rapidly developed resistance to most classes of antimicrobials used for treatment of gonorrhea (4,6,17,18,20). Penicillinase-producing N. gonorrhoeae (PPNG), with plasmid-mediated high-level resistance to penicillin, was first reported in 1976 (1, 14) and has since been disseminated worldwide (2). The first gonococcal strain with high-level clinical resistance to ceftriaxone, which is the last remaining option for first-line gonorrhea treatment, was recently found in Japan and completely characterized (9, 11). However, the resistance to ceftriaxone was chromosomally mediated, and no extended-spectrum ␤-lactamase (ESBL) has yet been identified in N. gonorrhoeae. If an ESBL did emerge in N. gonorrhoeae and spread internationally, gonorrhea would become an extremely serious public health problem. PPNG strains are rare in Japan, but these strains have remained highly prevalent in several other countries in Asia (19) and worldwide (20). Penicillin is still also used as the first-line drug in, e.g., some Pacific island countries and the northern part of Australia, because of maintained efficacy in the settings and its low cost.Although the ␤-lactamase (TEM) gene of authentic PPNG is the bla TEM-1 allele, a recently isolated PPNG in Thailand possessed the bla TEM-135 allele, which differs from the bla TEM-1 allel...

tested positive for chlamydia compared to 8 in the Clinic Group, and the rate of reinfection was 12.9% in the Home Group and 14.6% in the Clinic Group (p¼0.8).Conclusions Use of home-based, self-obtained vaginal swabs resulted in a significant increase in rescreening rates compared to rescreening in the clinic. Our findings indicate a role for home-based specimen collection as an alternative to clinic-based rescreening for chlamydia in women.Clinical sciences oral session 4: Treatment: Chlamydia, Gonorrhoea and related syndromes O3-S4