Background We describe a sexual network consisting of two males and five females who were tested for gonorrhoea at genital and oropharyngeal sites in early 2018, with the aim of exploring whether tongue kissing transmits gonorrhoea.

Methods Participants independently provided extremely detailed interview accounts of sexual activity with one another, to permit inter-participant verification. Testing for N. gonorrhoeae was by nucleic acid amplification testing (NAAT). Whole genome sequencing (WGS) was performed on available culture-positive samples to assess genomic relatedness between samples.

Results Sexual contact included tongue kissing for all participants, and many participants participated in oro-genital and genito-genital intercourse with one another. All sexual contact occurred during a 1-week period in Victoria, Australia. Two participants had samples available for WGS and these were highly related genomically, and these participants were separated in this network by two other participants. All seven participants had gonorrhoea, six participants had oropharyngeal gonorrhoea in the absence of genital gonorrhoea, and the other participant had only vaginal gonorrhoea. No men acquired urethral gonorrhoea.

Conclusion The fact that six of seven participants had oropharyngeal gonorrhoea in the absence of urogenital gonorrhoea supports the notion that tongue kissing is a common mode of gonorrhoea transmission. No men acquired urethral gonorrhoea from oro-penile sex, suggesting that transmission from oropharynx to urethra may be less likely than by tongue kissing. Our WGS results, when viewed in conjunction with the extremely-detailed sexual behaviour data, support the notion that gonorrhoea diagnoses in this network were likely the result of within-network transmission. Our findings highlight the need for more research to define the transmission routes for gonorrhoea in heterosexuals, to inform screening policies.

Disclosure No significant relationships.