PT - JOURNAL ARTICLE AU - Xianglong Xu AU - Eric P F Chow AU - Jason J Ong AU - Christian J P A Hoebe AU - Deborah Williamson AU - Mingwang Shen AU - Fabian Yuh Shiong Kong AU - Jane S Hocking AU - Christopher K Fairley AU - Lei Zhang TI - Modelling the contribution that different sexual practices involving the oropharynx and saliva have on <em>Neisseria gonorrhoeae</em> infections at multiple anatomical sites in men who have sex with men AID - 10.1136/sextrans-2020-054565 DP - 2021 May 01 TA - Sexually Transmitted Infections PG - 183--189 VI - 97 IP - 3 4099 - http://sti.bmj.com/content/97/3/183.short 4100 - http://sti.bmj.com/content/97/3/183.full SO - Sex Transm Infect2021 May 01; 97 AB - Background The spectrum of sexual practices that transmit Neisseria gonorrhoeae in men who have sex with men (MSM) is controversial. No studies have modelled potential Neisseria gonorrhoeae transmission when one sexual practice follows another in the same sexual encounter (‘sequential sexual practices’). Our aim was to test what sequential practices were necessary to replicate the high proportion of MSM who have more than one anatomical site infected with gonorrhoea (‘multisite infection’).Methods To test our aim, we developed eight compartmental models. We first used a baseline model (model 1) that included no sequential sexual practices. We then added three possible sequential transmission routes to model 1: (1) oral sex followed by anal sex (or vice versa) (model 2); (2) using saliva as a lubricant for penile–anal sex (model 3) and (3) oral sex followed by oral–anal sex (rimming) or vice versa (model 4). The next four models (models 5–8) used combinations of the three transmission routes.Results The baseline model could only replicate infection at the single anatomical site and underestimated multisite infection. When we added the three transmission routes to the baseline model, oral sex, followed by anal sex or vice versa, could replicate the prevalence of multisite infection. The other two transmission routes alone or together could not replicate multisite infection without the inclusion of oral sex followed by anal sex or vice versa.Conclusions Our gonorrhoea model suggests sexual practices that involve oral followed by anal sex (or vice versa) may be important for explaining the high proportion of multisite infection.All data relevant to the study are included in the article or uploaded as supplementary information. The data were all collected from published articles and reports. Data are available in the supplementary materials.