HIV drug resistance is caused by changes in the genetic structure of HIV that affect the ability of medicines to block the replication of the virus. When this occurs, people can lose the benefits of treatment unless health systems are able to detect resistance early and switch patients to alternative therapies. Monitoring these changes—known as HIV drug-resistance surveillance—is essential to keeping treatment working, protecting public health investments, and preventing the spread of harder-to-treat HIV.
In this Q&A, we speak with Dr. Juliana da Silva (2024 North America Cohort B), a physician, epidemiologist, and public health expert who has spent years working at the intersection of science, policy, and country-led health systems, about why sustaining drug-resistance surveillance is so critical, the challenges of doing this work in real-world settings, and what gives her hope for the future of HIV care.
What are the most urgent challenges that the global health community faces in addressing HIV drug resistance right now?
One of the most urgent challenges is sustaining HIV drug-resistance surveillance. The global health community is still learning how to build surveillance platforms that are sustainable, country-owned, and integrated into routine care.
For example, 97% of people living with HIV in Sub-Saharan Africa use the same drug regimen, called dolutegravir, but many countries don’t yet have systems that can detect when resistance emerges and put forth strategies to mitigate it and ensure timely switches to alternative regimens. This creates blind spots where resistance can develop silently.
Another challenge is bringing to market technologies that make drug-resistance testing simpler and more affordable. HIV resistance testing relies on the same sequencing platforms used to detect emerging pathogens. That’s a strength—because building HIV sequencing capacity also strengthens broader genomic surveillance—but it also requires specialized labs and a workforce that is hard to scale and sustain. We really need technologies that simplify testing in the same way that we simplified HIV diagnostics and treatment monitoring.
Finally, translating science into policy remains a major hurdle. We have strong evidence, but ensuring that ministries, donors, and implementers can act on that evidence requires coordination and political will. Drug resistance sits at the intersection of clinical care, laboratory systems, procurement, and policy; aligning these pieces is an ongoing challenge.
Can you share a moment from your work where you encountered a significant barrier and describe how you overcame that barrier?
An example comes to mind is a project I worked on with my team on the implementation of a surveillance network. In international collaborations, there are often unspoken tensions around data sharing, ownership, and the perceived burden on already stretched teams. It is important to navigate these tactfully and to build trust early.
What helped us move forward was walking into the discussion acutely aware of these tensions and ready to mitigate them. We were upfront about country ownership, built a shared understanding for data sharing, and were flexible in adapting the protocol to country realities while still keeping certain standards that would allow comparability.
Once countries saw that the platform was designed to strengthen their own capacity—not extract data—the momentum shifted. Today, those same countries are leading the next round of surveillance, we have collectively built the largest database on HIV drug resistance globally, and this project is informing global guidance.
That experience reinforced for me that progress in global health depends as much on relationships and respect as it does on science. It also underscores the importance of designing programs that truly strengthen the capacity of organizations and countries where the work is located.
As treatments advance and technology evolve, what are the biggest opportunities and challenges for managing HIV drug resistance in the next 5–10 years?
We are entering a period with extraordinary scientific opportunity. Long-acting regimens could fundamentally reshape how we approach HIV treatment and have a real impact on drug resistance. Partial adherence is still the main driver of resistance, and making treatment easier—by reducing dosing frequency, daily burden, and stigma—has the potential to be transformative. The possibility of regimens that maintain suppression despite intermittent adherence is especially important in the settings where I work.
But to realize their full impact, these innovations need to be studied and implemented in a way that reflects how care is actually delivered. For example, when clinical trials for long-acting agents require extensive testing or very frequent monitoring, it can slow our ability to generate evidence that shows these regimens are feasible and effective in programs where resources for treatment monitoring are limited.
Another hurdle is ensuring timely access for low- and middle-income countries once these products come to market. The opportunity is enormous, but only if these regimens are designed from the outset to be scalable and implementable in the health systems that will ultimately determine their real-world impact.
What gives you the most hope when you think about the future of HIV care, the role of leadership, and the effort to end drug-resistant HIV?
We are in a moment in global health where, despite many challenges, we are effectively shifting decision-making and ownership to countries. What gives me hope is knowing there are leaders, many of them women, who are ready to take this up. I’ve worked alongside many of them, and their expertise, drive, and commitment make me believe that the HIV response will continue, not because funding is guaranteed, but because their willpower and determination will not let it fade.