Antimicrobial resistance in Neisseria gonorrhoeae

Sexually transmitted infections (STIs) are common, particularly in high-risk groups such as men who have sex with men (MSM) who are taking HIV pre-exposure prophylaxis (PrEP). Globally, bacterial STIs with antibiotic resistance, such as gonorrhoea, are increasingly common. Neisseria gonorrhoeae, the bacterium that causes gonorrhoea, is able to develop antibiotic resistance by taking up genetic material from other bacteria. This process presumably takes place during an infection in the throat. Part 1 of this thesis shows that MSM who use PrEP have more resistant throat bacteria than the general population, even if they have not used antibiotics recently. This is possibly a consequence of frequent antibiotic use in the MSM population as a whole. It is also possible that transmission of (resistant) throat bacteria between individuals plays a role – intimate partners appear to have a similar throat microbiome. Part 2 of this thesis examined whether a mouthwash can be used as a non-antibiotic alternative for prevention of STIs or for treatment of gonorrhoea in the throat. This proved to be ineffective in both cases. Therefore, we currently have no other option than to treat gonorrhoea with antibiotics. Our findings in PrEP users show that antibiotics should be used sparingly and in a targeted fashion, especially in MSM who use PrEP.