Effects of Improved Partner Notification on the Transmission of HIV and N. Gonorrhoea Among Men Who Have Sex With Men: A Modelling Study

Abstract

AbstractMen who have sex with men (MSM) are disproportionally affected by HIV in the Netherlands. Partner Notification (PN) is an important element of controlling the transmission of sexually transmitted infections (STIs) and HIV. We investigated the effects of improving PN on the transmission of HIV and N. gonorrhoeae (NG) among MSM in the Netherlands.We developed an agent-based model that describes the transmission of HIV and NG among MSM. In the baseline scenario 14.3% and 29.8% of casual and steady partners of the index case get notified and tested for HIV/STI after three weeks (percentage notified and tested, PNT). We examined the following scenarios: 1) Increase PNT to 41% for both partner types; 2) Decrease the time between index and the partners tested to one week; 3) Combine scenario 1 and 2. Effects are expressed as cumulative change from the baseline simulation over 15 years.Increasing PNT could lead to a decrease in gonorrhea cases of 45% (IQR: 39.9 – 49.9%), with an increase in number of HIV/STI tests of 4.4% (IQR: 1.6 – 7.3%), but no change in HIV infections (−5.4%; IQR: -21 – 7.9%). Decreasing time between tests could lead to a change in new NG infections of -14.2% (IQR: -17.2 – -10%), no change in HIV infections (8.2%; IQR: - 1.3 – 20%) or in number of HIV/STI tests performed (−0.4%; IQR: - 1.5 – 0.6%). Scenario 3 led to a change in NG infections of -56.8% (IQR: - 63.8 – - 47.4%), no change in HIV infections (11.5%; IQR: -11.1 – 33.9%) or in number of HIV/STI tests (− 0.5%; IQR: - 4.9 – 4.3%).Increasing the percentage of sexual partners notified and tested for HIV/STI may have only a small effect on HIV, but could reduce the number of new NG infections substantially. However, it could lead to an increase in the number of HIV/STI tests performed.Key messagesWhat is already known on this topic: Notifying recent sexual partners of people diagnosed with HIV or other sexually transmitted infections (STI) can promote timely testing and early treatment, thereby reducing further transmission of STIsWhat this study adds: We quantify the effects of improving partner notification on the transmission of two STIs simultaneously.How this study might affect research, practice or policy: In our scenarios, increasing the percentage of partners who get notified and tested had a bigger impact than decreasing the time between testing the index and his partners.