Successfully addressing HIV in a population requires navigating complex landscapes affected by many variables, including social and behavioral factors that can be difficult to pin down. By using equations to simulate, analyze, and predict the dynamics of HIV infection, mathematical modeling offers a way for public health programmers to better understand the dynamics of the epidemic and respond more effectively.

To improve the availability of information on the HIV epidemics and its response in Brazil, Avenir Health—working closely with Brazil’s Ministry of Health (MOH), the US Centers for Disease Control and Prevention (CDC), and ICAP at Columbia University—developed mathematical models using the Spectrum AIDS Impact Model (AIM) at national and sub-national levels.

Created by Avenir Health and used by UNAIDS to estimate key HIV indicators, such as incidence, prevalence, and AIDS-related deaths, AIM helps countries estimate key HIV indicators for a country or region such as age and sex for people living with HIV, new infections, AIDS deaths, mother-to-child transmission, antiretroviral (ART) coverage, and more. These estimates and projections are based on country-specific demographic, service, survey, and surveillance data and global epidemic patterns.

In Brazil, the mathematical models developed through AIM were used to estimate key HIV indicators at the national level, for two states (Paraná and São Paulo), and for all 27 state capitals. These indicators included the number of people living with HIV (PLHIV), new HIV infections, AIDS-related deaths, and progress toward achieving the UNAIDS 95-95-95 targets, which provide countries with a roadmap for achieving HIV epidemic control.

To build the capacity of local public health experts to develop AIDS Impact Models and to train others in their use, ICAP supported a three-day workshop in the nation’s capital, Brasilia. The workshop, which supported the sustained application of mathematical modeling to generate robust, high-quality estimates of key HIV indicators, was attended by 20 people, including teams from ICAP and CDC Brazil offices, MoH staff, and staff from the Municipal Health Secretariats (SMS).

The workshop combined lectures, hands-on practical exercises, and interactive discussions, with the goal of strengthening technical skills, presenting modeling results, and facilitating critical interpretation and discussion of the data. Participants assessed model outputs and evaluated the usefulness of the results for HIV planning, monitoring, and decision-making.

Mathematical Modeling Workship Attendees (l-r): Roberto Paulo Braz Júnior, Ana Paula Betaressi da Silva, Erika Fazito, Ana Roberta Pati Pascom, Mariza Tancredi, Nazle Mendonça Collaço Véras, Cléa Elisa Ribeiro, John Stover, Sumire Sakabe, Ana Carolina Santelli, Rob Glaubius, Barbara Scoralick Villela, Matheus Pacheco de Andrade, Bianca Ledur Monteiro, Rui de Gouveia Soares Neto, Amanda Krummenauer, and Filipe Perine

The workshop received a positive reception from attendees.

A technical advisor from Brazil’s Ministry of Health commented, “These were three days of intense learning, and I had the opportunity to significantly deepen my understanding of how to interpret the results produced by AIM.”

Another MOH technical advisor noted that the training would “support decision-making and planning, enabling truly evidence-based management.”

“It was extremely valuable in every respect,” stated an official from the Chronic Communicable Disease Surveillance Unit of the SMS.

“Sub-national mathematical modeling can be a gamechanger for a country like Brazil that really needs to focus its HIV programming on where it can yield the greatest return on investment,” said Erika Fazito, DHSc, director for ICAP in Brazil. “When it comes to maintaining progress in this uncertain time for global health, trainings like this one can make a real difference.”

About ICAP

A major global health organization that has been improving public health in countries around the world for two decades, ICAP works to transform the health of populations through innovation, science, and global collaboration. Based at Columbia Mailman School of Public Health, ICAP has projects in more than 40 countries, working side-by-side with ministries of health and local governmental, non-governmental, academic, and community partners to confront some of the world’s greatest health challenges. Through evidence-informed programs, meaningful research, tailored technical assistance, effective training and education programs, and rigorous surveillance to measure and evaluate the impact of public health interventions, ICAP aims to realize a global vision of healthy people, empowered communities, and thriving societies. Online at icap.columbia.edu