Abstract / Summary
Abstract Background New HIV diagnoses among men who have sex with men (MSM) in the Netherlands have declined considerably, but the recent plateau suggests ongoing transmission. In 2024, 29% of new diagnoses among MSM were late stage, showing that the time between infection and diagnosis can still be reduced. In low-incidence settings, infections introduced through immigration are increasingly important in sustaining transmission. Methods We used an agent-based model of HIV transmission among MSM in the Netherlands, incorporating infections acquired domestically and abroad. For 2026 – 2040, we simulated testing interventions focused on immigrants at entry, resident MSM subgroups, and combinations of these. Results Entry testing of immigrating MSM averts up to 94 (95-th % quantile interval, 95% QI -128 – 328) infections over 15 years if at least 50% take the test. Testing every 7 months in the general MSM population achieves the largest reduction, up to 508 (95% QI 292 – 900) infections averted. The same rate in MSM with more than 5 recent partners results in 340 (95% QI 132–592) infections averted. Combining entry testing with 7-monthly testing in the general resident MSM population results in 534 infections averted (95% QI 308–884). Considering both impact and additional tests per infection averted, combination strategies generally offer the most favourable trade-offs. Conclusions Increased testing in resident MSM, particularly when combined with entry testing of immigrating MSM, can substantially reduce HIV infections while offering an attractive testing effort. The higher impact of targeting the general MSM population compared with targeting those with high recent partner numbers suggests that the criteria used to identify individuals with undiagnosed HIV need to expand.