PReventing the Emergence of untreatable STIs via radical Prevention

Resistance to common sexually transmitted infections (STIs) like gonorrhoea is increasing so fast that
experts are worried that they may no longer be treatable with any antibiotics in the not too distant
future. In this proposal, we want to take the first steps towards addressing the root cause of this
problem. This is the excessive use of antibiotics, particularly in groups that have high rates of STIs, such
as men who have sex with men (MSM) taking PrEP (a pill to prevent HIV). The link between antibiotic
consumption and antibiotic resistance is frequently missed as the pathway is often not direct but goes
via other commensal or ‘good’ bacteria that all of us have in our microbiomes. Antibiotics first select
for resistance in the commensal bacteria, and they then pass the resistance genes on to gonorrhoea.
We plan to make use of this fact to set up a system to monitor the increase in resistance in these
‘good’ bacteria that are associated with antibiotic use in populations. We will do this in our local PrEP
cohort and collaborators from other centers around the world will do a similar thing. We will then use
this information to show the patients themselves as well as the doctors who care for these patients
how consuming excess antibiotics leads to resistance in the ‘good’ bacteria. We expect this process
will help reduce the amount of antibiotics used in these key populations and thereby address the root
cause of resistance. We will also be investigating if we can find STI treatments that are less likely to
produce antibiotic resistance. One treatment we will try to develop is a bacteriophage against
gonorrhoea. This is a virus that is deadly to gonorrhoea but harmless to humans and other bacteria
and would enable us to treat gonorrhoea without selecting for antibiotic resistance.