Gender disparities and treatment cascade gaps in The Gambia’s HIV epidemic: 35-year trends, male disadvantage, and scenarios toward UNAIDS 2030 targets

Despite low human immunodeficiency virus (HIV) prevalence in The Gambia (estimated adult prevalence 1.29% in 2024), the country faces a substantial burden, with approximately 25,000 people living with HIV, over 1,100 new infections, and approximately 1,200 acquired immunodeficiency syndrome (AIDS)-related deaths annually as of 2024. Gender disparities and treatment cascade gaps threaten Joint United Nations Programme on HIV/AIDS (UNAIDS) 2030 elimination targets. We examined 35-year epidemic trajectories (1990–2024), quantified gender-specific cascade performance and retention efficiency at critical transitions, and projected future scenarios under three intervention scenarios to inform national HIV strategies. We analyzed UNAIDS 2025 HIV data/estimates for The Gambia (1990–2024) for people living with HIV (PLHIV), new HIV infections, AIDS-related deaths, and prevalence by sex. Annual percent change (APC) was calculated using log-linear regression across epidemic phases. Treatment cascade performance was assessed through cascade achievement, retention efficiency, and gaps to UNAIDS 95-95-95 targets. Future trajectories (2025–2030) were projected under status quo, optimistic (10% improvement), and pessimistic (10% deterioration) scenarios. PLHIV increased from 1,035 (95% UI: 426-1,807) in 1990 to 25,247 (19,689 − 31,811) in 2024, with phases of early expansion (+ 31% annually, 1990–1999), peak transmission (+ 6%, 2000–2009), treatment scale-up (+ 1%, 2010–2019), and decline (-1%, 2020–2024). Women comprised 61% of PLHIV by 2024, with female-to-male prevalence ratio rising from 1.06 to 1.57. The 2024 treatment cascade (64% diagnosed, 44% on ART, 35% virally suppressed) fell below UNAIDS 95-95-95 targets. Male disadvantage emerged across stages: diagnosis (53% vs. 72% women, 19pp gap), ART coverage (27% vs. 55%, 28pp gap), and viral suppression (21% vs. 44%, 23pp gap). ART initiation was the main cascade bottleneck: 51% of diagnosed men versus 76% of women-initiated treatment (p < 0.001), while suppression rates on ART were similar (78% vs. 80%, p = 0.089). Projections to 2030 showed infections decreasing 6% to 1,055 under status quo, declining 27% to 826 under optimistic scenarios (preventing 1,374 infections), or increasing 13% to 1,265 under pessimistic scenarios, highlighting intervention fragility. The Gambian HIV epidemic shows a demographic decline, driven by deaths exceeding new infections rather than treatment-mediated viral suppression with persistent gender gaps. ART initiation remains the main bottleneck, with only 51% of diagnosed individuals starting treatment, particularly men. Meeting UNAIDS 2030 targets requires male-targeted testing, same-day ART initiation, and gender-stratified monitoring. A 10% annual improvement in prevention and cascade performance is needed to prevent 1,374 infections by 2030. Not applicable.