new cases of HIV have dropped by 20% in Scotland following the roll-out of PrEP. While positive results in health clinics had fallen by 43%.

“We show that it is possible to achieve important reductions in HIV incidence in men who have sex with men when PrEP is implemented within routine care,” the researchers say.

“Our findings suggest that PrEP can make a wider contribution, alongside other prevention interventions, in reducing population level risk of HIV for those not on PrEP.”

Those prescribed PrEP at least once had 75% less positive results, and even those who had never taken it saw a reduction of 32%, suggesting those using PrEP benefited their sexual partners too.

Medication is administered nationwide throughout Scotland for free – and has been since 2017 – on the basis of one of these conditions: being a sexual partner of an HIV-positive person who has a detectable viral load; having a bacterial rectal STI in the past year; reporting condomless anal sex with two or more partners in the past year; or being at “equivalent high risk of HIV acquisition”, as agreed by a clinician.