INCLIVA Healthcare Research Institute-University Clinical Hospital of Valencia, the Universitat Politècnica de València - through its VRAIN Institute, the Valencia Anti-AIDS Committee and the Centre for Epidemiological Studies on Sexually Transmitted Infections and AIDS in Catalonia (CEEISCAT) have joined forces to develop a spatial intelligence platform to support health policy decisions aimed at optimising the prevention of human immunodeficiency virus (HIV) and accelerating its early diagnosis.

The HIVision Spain project, which won an award in the Prevention category at the second edition of Visionarium Innovation by Gilead, proposes a paradigm shift in the approach to HIV, moving from a historically reactive response to a predictive, prevention-focused approach that anticipates scenarios.

"HIVision Spain is a national HIV simulator, a digital twin, designed to support health policy decisions and resource allocation to help end the HIV epidemic in Spain by closing persistent gaps in diagnosis, particularly early diagnosis, and unequal coverage of pre-exposure prophylaxis, known as PrEP, a key strategy in HIV control, especially in vulnerable populations. In terms of equity, it will focus on structurally invisibilised subpopulations and encourage co-creation with community organisations, ensuring the acceptability and cultural relevance of interventions," explains Dr Anaïs Corma, from the Cardiometabolic and Renal Risk Study Group at INCLIVA and the Infectious Diseases Unit, Internal Medicine, at the University Clinical Hospital of Valencia, and principal investigator of this project.

The model validates its predictive capacity based on historical data and is then recalibrated with current and field data in sequential phases (in Valencia and Barcelona), enabling it to predict how the epidemic will vary when different factors are modified. The platform runs "what if" scenarios that quantify the expected impact based on clinical, behavioural, and territorial data, providing actionable metrics and micro-plans ready for adoption. The goal of the 18-month project is to develop a tool that allows selecting the best intervention based on the epidemiological moment, the target population and the available resources, accelerating early diagnosis, optimising prevention and advancing equity.

Despite recent advances, the current response to HIV in Spain continues to show persistent gaps in early diagnosis and combined prevention, which sustain the incidence and perpetuate inequalities. The rate of new diagnoses has remained relatively stable since 2021, and the proportion of late diagnoses has not decreased significantly. Today, more than 50% of diagnoses are at a very advanced stage of the disease, leading to higher morbidity and mortality and associated high healthcare costs.

International recommendations emphasise the importance of expanding systematic screening in clinical services, integrating it into primary care and bringing it closer to vulnerable populations, including rapid same-day diagnosis and treatment pathways. However, structural, social and programmatic barriers (stigma, dependence on hospital services, long waiting times and a shortage of decentralised access points) persist in Spain, preventing a fully adequate response.

The innovation of HIVision Spain lies in the creation of a multiscale computer-based simulator with membranes previously applied to sexually transmitted infections by the research team.

The model will represent the population dynamics of HIV in Spain in an integrated manner, including stratification by higher-risk subpopulations and actual care pathways.

It will incorporate four interconnected layers: a geospatial layer to prioritise high-return micro-territories; a behavioural layer reflecting testing frequency, linkage and access/persistence in PrEP; a clinical layer reproducing the diagnostic and therapeutic cascade up to viral suppression; and a programmatic layer incorporating capacity constraints, waiting times and community deployments.

The aim is not to replace existing information systems, but to complement them with a predictive and operational tool that translates local evidence into implementable micro-plans. In this way, clinicians, managers and community organisations will have a tool that quantifies the expected impact of each combination of screening, rapid linkage and PrEP, under realistic implementation conditions.

The project is structured in two main phases. Phase I, already underway and independently funded, involves participatory mapping, community screening and population size estimation in Valencia. This empirical data will feed into the calibration of the simulator.

Phase II, covered by the proposal selected in the second edition of Visionarium Innovation by Gilead, corresponds to the development and implementation of the multiscale simulator. It includes an initial stage of engine optimisation and formal design of scenarios and agents, followed by national parameterisation with surveillance data. Subsequently, empirical calibration will be carried out in Valencia, external validation in Barcelona and hierarchical extension to the whole of Spain.

In addition to Anaïs Corma, María José Galindo, also from INCLIVA's Cardiometabolic and Renal Risk Study Group and the Infectious Diseases Unit, Internal Medicine, at the University Clinical Hospital of Valencia; José Canales, from the Valencia Anti-AIDS Committee; José María Sempere and Marcelino Campos, from VRAIN at the UPV; and Cinta Folch, Helena González and Georgia Escaramis, from CEEISCAT.