BACKGROUND: A disco matanga, or "disco funeral," is a celebration of a decedent's life that is culturally important in parts Africa, often involving overnight travel and alcohol consumption. These are known risk factors for HIV, which is prevalent in many areas where disco matanga is practiced. However, the contribution of disco matanga to HIV transmission is not well-understood. We used agent-based network modeling to estimate how disco matanga impacted HIV transmission, and to explore the impact of relevant biomedical, biobehavioral, and structural interventions to reduce HIV risk. METHODS: We adapted EMOD-HIV, a previously validated network-based model of HIV in the Nyanza region of Kenya, to incorporate disco matanga assumptions informed by literature review. Occurrence of disco matanga was modeled to occur following any death in the population. We compared past HIV incidence (1980-2024) with and without incorporating disco matanga, and future HIV incidence (2025-2050) with different interventions for disco matanga attendees: (1) biomedical (HIV prophylaxis), (2) biobehavioral (reduction in condomless sex partners), (3) structural (female empowerment to avoid unwanted sex). We estimated HIV infections and deaths averted in the overall population, with sensitivity analysis around intervention uptake. RESULTS: Over 1980-2024, disco matanga contributed 7.8% (95% CI: 5.5-9.3%) of all HIV infections, an effect that peaked at 9.9% (95% CI: 6.4-12.0%) in the year 2004, coinciding with a peak in all-cause mortality due to HIV/AIDS. Biomedical prevention at disco matanga could avert up to 9.7% (95% CI: 8.9-10.5%) of adult HIV infections and 2.3% (95% CI: 1.9-2.6%) of deaths
biobehavioral 2.9% (95% CI: 2.1-3.6%) of infections and 0.9% (95% CI: 0.6-1.2%) of deaths
and structural 1.2% (95% CI: 0.5-1.8%) of infections and 0.5% (95% CI: 0.2-0.7%) of deaths. Results were highly sensitive to intervention uptake. CONCLUSIONS: We conducted the first modeling study, to our knowledge, simulating the interactions between disco matanga, HIV/AIDS, and intervention options. We found that biomedical, biobehavioral, or structural interventions implemented during disco matanga could substantially reduce HIV transmission and mortality in the Nyanza region. Research is needed to understand the feasibility and acceptability of HIV interventions tailored to local cultural practices.