Table 1.

Non-exclusive list of possible criteria for evaluating net utility of screening six specific STIs in MSM PrEP cohort^a.²³

	N. gonorrhoeae	C. trachomatis	M. genitalium	T. pallidum	HIV
Are host-pathogen interactions amenable to screening?
1. Undetected infection typically associated with serious adverse clinical outcomes	+	+	−	+++	+++++
2. Long period between infection and disease onset	−	−	−	++	+++
3. Not spontaneously cleared by immune system	−	−	−	+++	+++++
4. Natural immunity from recovered infection	+++	+	+++	+	++++
High risk of inducing AMR?
1. High risk of inducing AMR in pathogen itself given standard therapy	++++	+	++++	+	−
2. High risk of inducing AMR in microbiome given standard therapy	+++	++	+++	+

Example 1. For the first criterion, there is little or no evidence that MG is associated with serious adverse clinical outcomes and MG is thus scored ‘−’, whereas there is plenty of evidence that HIV is associated with severe outcomes and HIV is thus scored ‘+++++’.

Example 2. In the case of HIV for the fourth criterion, an HIV infection is not eradicated by the immune system and thus there is no immunity. HIV thus gets a favourable score for being amenable to screening on this criterion.

^aThis scoring is not based on a systematic review but on a subjective assessment of the authors’ evaluation of the scientific literature. Each infection is rated from ‘−’ to ‘+++++’ according to the evidence base underpinning the criterion and the clinical significance.