Editorial: Community-centric strategies for HIV and STI prevention in key populations

Key populations-women, adolescents, gender-diverse people, people who inject drugs, and historically underserved racial and ethnic groups-remain disproportionately vulnerable to HIV and STIs. Barriers include limited research designed for their needs, insufficiently trained staff, and the persistence of stigma and discrimination within healthcare settings [1,2]. Although biomedical innovation has accelerated, gaps persist in translating these advances into equitable access. Community involvement is often limited or introduced too late, resulting in prevention strategies that do not reflect the lived realities of those most affected [3].This editorial summarizes the contributions of five manuscripts included in this Research Topic, each highlighting community-centred approaches that strengthen HIV and STI prevention across diverse global settings.Vietnam's national roll-out of oral PrEP across 219 clinics in 29 provinces demonstrates how community engagement strengthens implementation. Collaboration with key-population-led organizations guided differentiated service models that improved confidentiality, reduced stigma, and addressed travel barriers. Month-3 continuation rates surpassed national averages as individuals selected service models aligned with their evolving preferences.The Vietnam experience underscores the importance of flexibility and user-driven choice, enabling integration of new PrEP modalities as they emerge.The HPTN 094 study on women who use drugs-a subgroup with overlapping needs 35 related to addiction care, reproductive health, parenting responsibilities, unstable housing, and 36 significant social stigma. A mobile health unit provided integrated services, including 37 contraception, addiction treatment, HIV prevention, primary care, and peer navigation. The manuscripts collectively demonstrate that prevention succeeds when communities recognize 87 themselves in the research design, the service delivery models, the messages, and the policies 88