By Dr. Karin Hatzold, Director of Global HIV, TB and Viral Hepatitis Programs
The consequences of climate change all have direct effects on human health. As the climate crisis accelerates, the future of global health will be shaped not only by rising temperatures and extreme weather events but by how we protect the most vulnerable groups, particularly those already navigating fragile health systems, chronic conditions, and intersecting inequities.
Climate change is ushering in an era of new and intensified disease outbreaks and pandemics. While global attention on climate and health often focuses on heat-related illnesses or mosquito-borne diseases, the less visible but equally urgent impacts are unfolding in communities affected by HIV, tuberculosis, and viral hepatitis. These diseases thrive in the same conditions that climate change exacerbates — displacement, food insecurity, overcrowded housing, and overwhelmed health services. Around 3.6 billion people live in regions highly susceptible to climate change, and many of those populations are disproportionately affected by HIV, TB and viral hepatitis. The latter is particularly true for marginalized groups who are least equipped to cope with the effects and often bear the brunt of these impacts. And yet, they are too often sidelined in climate resilience and pandemic preparedness discussions.
At PSI, we believe the path to climate-resilient health systems must be rooted in the lived experiences of people and communities on the front lines. It starts with strengthening how we prevent, diagnose, and manage HIV, TB, and hepatitis in the face of a changing climate.
One of the most effective approaches we have deployed in recent years is self-care, particularly through HIV and hepatitis C self-testing. In settings where climate shocks such as floods, droughts, or cyclones interrupt access to clinics or supply chains, the ability for individuals to test themselves safely and privately can mean the difference between knowing their status and falling through the cracks.
Self-testing empowers individuals, reduces dependency on overburdened health facilities, and sustains access during emergencies or movement restrictions. These lessons were reinforced during the COVID-19 pandemic and climate-related disasters alike. We are now building on this by piloting integrated self-care models, bundling HIV and hepatitis testing with access to information on sexual and reproductive health, mental health, and linkage to treatment.
Our HIV, TB, and hepatitis prevention and care interventions and programs are grounded in differentiated, client-centered service delivery that adapts to the realities people face. This means bringing care closer to home through community-led testing, peer navigation, mobile outreach, and community pharmacies — especially for those most likely to be left behind: key populations, migrants, adolescents, and people who use drugs.
By shifting care out of static clinics and into the hands of trained community providers and networks, we are not only reducing stigma and improving outcomes, but building locally owned, climate-resilient service delivery systems. These approaches also enable rapid re-deployment during public health emergencies.
Our work across all three disease areas is deeply interconnected with other health needs, particularly sexual and reproductive health, family planning, and noncommunicable diseases. At the primary healthcare level, we are investing in service integration that recognizes people do not experience their health needs in silos.
For example, a woman engaging with a community health worker for contraception should also be able to access HIV prevention, hepatitis B vaccination, or TB screening. This kind of integrated, person-centered care not only improves health outcomes, it also strengthens the entire system’s ability to absorb and adapt to future shocks, be they climate-induced or pandemic-related.
PSI’s investments in HIV, TB, and viral hepatitis are platforms for building the health systems of the future. Through these initiatives, we have pioneered innovations like community-led service delivery models, rapid diagnostics, differentiated care, and rights-based advocacy, that are essential to tackling new and emerging threats.
What the climate crisis demands is exactly what these programs are developing: equitable, decentralized, people-powered health systems that can flex, adapt, and continue delivering under stress. However, the work is far from over and advancing these efforts requires comprehensive and ambitious approaches to ensure sustainable disease response in the context of shifting pandemic, intensifying climate emergency, and increasingly complex global landscape. We must act now, and we must commit greater attention, investment and action to the multidimensional intersections of climate change, infectious diseases, and health. Only with stronger cross-sector collaboration — equally focusing on the environmental, health, and social components — can we create systems that leave no one behind.
