Sustaining two decades of PEPFAR's response to global HIV/AIDS: mitigating the impact of climate threats

Introduction

Climate shocks like storms, floods, droughts, and heat waves are having profound, disruptive impacts on health systems worldwide. In high HIV-burden countries, especially in sub-Saharan Africa and Southeast Asia, climate change is a threat multiplier, with the potential to undermine and even reverse hard-won progress in the fight against HIV. The upcoming United Nations Climate Change Conference (more commonly known as COP29) in Baku, Azerbaijan, is an important venue to highlight how the President's Emergency Plan for AIDS Relief (PEPFAR) is prioritizing both adaptive and mitigating strategies that can ensure HIV programs advance toward the UNAIDS goal of ending HIV as a public health threat [1], while also pursuing health equity and environmental sustainability, which are essential to ensuring health system resilience in the face of climate-related shocks.

Assessing the impact

Across the globe, climate-related disasters, tropical storms, and hurricanes have increased fivefold in the last 50 years, resulting in substantial loss of life and massive economic losses [2]. Moreover, the health impacts of climate change are likely to increase substantially in the coming two decades [3]. Not only will climate change increase the burden of most human infectious diseases, including spillover of zoonotic viruses from animal reservoirs like bats [4], and the risk of future pandemics like COVID-19, rising temperatures also threaten to fuel an increase in heat-related deaths [5]. For example, heat-related cardiovascular deaths are also expected to increase considerably; a study in Germany estimated that deaths from myocardial infarcts would increase by 18% and 63% per decade with a warming of 2°C and 3°C, respectively [6], while analysis in the United States has projected a doubling of cardiovascular deaths by the midcentury if temperature rises continue unabated [7]. The secondary effects of climate hazards through other social and economic impacts will be even broader and less predictable.

High HIV prevalence countries in sub-Saharan Africa and Southeast Asia are among the countries that have experienced the most significant increase in the frequency of climate-related shocks in recent years. The impact of Cyclone Idai in Mozambique, Malawi, and Zimbabwe in April 2019 offers a sobering case study of how climate-related disasters can profoundly impact health systems’ capacity to deliver routine services and respond to emergent humanitarian priorities. The Cyclone killed >1000 people, injured more than 2400 others, and precipitated US$ 2 billion in recovery costs [8]. It also disrupted HIV programming across Northern Mozambique [9]: Sofala province, for example, experienced a 25% decrease in drug pickups by clients and a 60% decrease in 3-month drug distribution in the month following the disaster (Fig. 1 ). PEPFAR and the Government of Mozambique's capacity to quickly adapt and respond to Cyclone Idai, prevented even worse outcomes; roofs were repaired on 37 healthcare facilities, and other clinics transitioned temporarily to tents to ensure essential HIV programs were maintained. By the end of May 2019, antiretroviral pickups in Mozambique had increased to 85% of precyclone levels, and three-month drug distribution approached precyclone levels. While offering a positive example of HIV-related health system resilience in the face of climate-related disasters, this case study also provides a stark warning of what is likely to become commonplace without aggressive, coordinated global action to mitigate climate change.

Fig. 1.

Assessing the impact of Cyclone Idai on HIV programs in Mozambique.

Source: Prepared using PEPFAR Panorama data. Notes: Immediately following the cyclone, PEPFAR/Mozambique utilized a UN-generated list of affected districts as well as a summary of HIV treatment data to determine the number of people with HIV affected, at both district and site levels. The team triangulated this information with aerial photographs of the flooding, maps and information gathered from HIV providers on the ground, to determine how to respond rapidly.

Fig. 1(Continued).

Assessing the impact of Cyclone Idai on HIV programs in Mozambique.

Source: Prepared using PEPFAR Panorama data. Notes: Immediately following the cyclone, PEPFAR/Mozambique utilized a UN-generated list of affected districts as well as a summary of HIV treatment data to determine the number of people with HIV affected, at both district and site levels. The team triangulated this information with aerial photographs of the flooding, maps and information gathered from HIV providers on the ground, to determine how to respond rapidly.

Despite the ominous warnings, significant evidence gaps remain an impediment in determining how health systems plan for future climate shocks in the near term [10]. There is also considerable uncertainty around how climate policy strategies will lead to differential impacts on HIV programming across diverse global regions and for different communities. Nonetheless, there is incontrovertible evidence that every aspect of HIV programming will be impacted by climate change in the long term. Storm surges and rising sea levels will affect healthcare facilities in coastal cities and Island nations. Rising temperatures, along with droughts and food insecurity, will drive increased migration, which may increase HIV transmission rates, especially in Eastern and Central Africa. A recent modeling study demonstrated that, if left unchecked, the escalating temperatures in sub-Saharan Africa could result in an 11% rise in HIV transmission in areas most severely affected by drought and food insecurity [11]. Faced with these future threats, not to mention the near prospect of more health system shocks like Cyclone Idai, PEPFAR is committed to addressing climate threats as part of sound and evidence-based operational planning, as outlined below.

PEPFAR's response to climate-induced health challenges

A central function of the new Bureau for Global Health Security and Diplomacy (GHSD), where PEPFAR now resides within the US Department of State, is marshaling global collective action to ensure that health systems are optimally responsive to climate hazards. While PEPFAR's mission remains clear – ending HIV as a public health threat – it will become increasingly important to support partner countries to adopt strategies that both adapt to climate-related threats while concurrently mitigating the impact of climate change. Building on lessons learned from the COVID-19 pandemic, PEPFAR's efforts to enhance health outcomes for communities impacted by HIV will increasingly require that partner countries strengthen the climate resilience and sustainability of their health systems. This comprehensive approach will be crucial for addressing the effects of climate change and preparing health systems to withstand and adapt to climate-related hazards.

Strategies that sustain the HIV response and mitigate climate change

The single most crucial HIV-specific intervention that can mitigate climate change is an intensification of efforts to prevent more infections and ensure that people with HIV live long, healthy lives. Given substantial healthcare-related greenhouse gas emissions [12], reducing HIV morbidity and mortality will contribute to substantial reductions in the carbon footprint of healthcare systems. As such, one of PEPFAR's most significant contributions to addressing climate change is finishing the fight to end the HIV epidemic, which is the main priority of its five-year strategic plan. However, another vital component of that strategic plan is a commitment to new models for delivering equitable access to life-saving health products [13]. The transition from efavirenz to dolutegravir (DTG), for example, is estimated to reduce total carbon emissions by 26 million tons of CO₂ equivalent by 2027, thanks to the shift to a treatment formulation that requires less active ingredients [14]. According to a recent UNITAID report, the adoption of DTG reduced the health sector's overall carbon footprint in low- and middle-income countries by approximately 0.3–0.4%, a magnitude of reduction – from one single drug – that surpasses many other climate mitigation achievements in the health sector [15]. While DTG's carbon footprint is significantly lower than its predecessor, it remains very high, equivalent to the annual emissions of the city of Geneva, Switzerland [14]. However, up to 40% of these emissions could be abated through cost-saving measures such as process optimization to improve energy and efficiency, and another 50% could be reduced by adopting green energy and materials. Consequently, PEPFAR aims to shift at least two million clients onto African-made first-line ARV treatments by 2030, and procure 15 million HIV tests produced by African manufacturers by 2025 [13]. A strong regional manufacturing capability in Africa could have tremendous health, national security, and climate benefits. While these efforts were instituted for various reasons, including programmatic efficiency and sustainability, the climate co-benefits are clear: they will further shrink PEPFAR's carbon footprint and improve the climate resilience of its US$ 750 million investment in commodities.

Strategies that build climate resilience and optimize client-centered programs for people with HIV

PEPFAR's support to countries also includes strategic investments that build health system resilience to withstand climate-induced disruptions, including working closely with National Public Health Institutions to establish that capacity. Recognizing the compounded risk of co-morbidities due to climate change, PEPFAR is focused on advancing person-centered health approaches that will concomitantly mitigate climate change [13]. Across multiple countries, PEPFAR is now supporting multimonth dispensing of HIV drugs, given compelling evidence that this improves clinical outcomes [16] and reduces both client and healthcare costs [17]. These strategies are also likely to substantially reduce healthcare-related carbon emissions. Additionally, PEPFAR is working with partner governments to adapt HIV programs to multifaceted health impacts from heat, vector, water, and food-borne diseases, along with health challenges exacerbated by climate change. In Haiti, for example, planned adaptations include developing tools that triangulate clinical and programmatic data to identify communities at risk for food insecurity and targeting resources accordingly.

Strategies that address the needs of health facilities and workers associated with PEPFAR

Over the last twenty years, PEPFAR programs have demonstrated the power of people-centered healthcare service delivery with solid partner government leadership and community engagement to deliver immediate impact, confront inequities, ensure contingency planning, and withstand moments of adversity. Nonetheless, PEPFAR was launched before the future effects of climate change were widely appreciated. Moving forward, sustaining the gains in the HIV response will require that PEPEFAR works with partner governments to address the needs of health facilities and workers to adapt and respond to new climate hazards. This includes supporting the 170 000 community health workers working in PEPFAR programs, many of whom are contending with the climate crisis as they work to deliver lifesaving HIV/AIDS care in rural communities across sub-Saharan Africa. It will also involve investing in cold-chain capacity to secure heat-intolerant commodities and increasing clean-energy-based electrification infrastructure for priority facilities, including through initiatives like Power Africa [18]. As such, PEPFAR and collaborators, including Africa's network of National Public Health Institutes, can extend its legacy of innovation and research to help countries identify optimal strategies to build resilience in the face of new and emerging climate-related health threats. Creating an evidence base for how to deliver high-quality HIV programs in settings that are vulnerable to seasonable flooding and/or heatwaves can also ensure that PEPFAR and its partner governments are not only able to respond to the immediate challenges posed by a changing climate but also promulgate strategic, forward-looking efforts to protect and advance global health achievements in an increasingly uncertain future.

Conclusion

Since its inception in 2003 PEPFAR has demonstrated the power of global collective action, underpinned by rigorous science and data-driven strategies, to confront and significantly mitigate public health crises. Saving over 25 million lives and providing >20.5 million people with life-saving HIV treatments [19], PEPFAR stands as a testament to what can be achieved in response to a common threat. PEPFAR offers a model for the world on how to navigate and counteract the multifaceted health threats amplified by climate change, ensuring the sustainability of health gains for generations to come.

Acknowledgements

Funding: M.J.A.R., M.D., R.B., M.B. H.C., J.K. are all employed by the US government. T.M. is not employed by the US government.

Author contributions: M.J.A.R. drafted the original paper; M.D. developed visualizations; M.J.A.R., R.B., M.B., H.C., T.M. and J.K. reviewed and revised subsequent drafts. All authors reviewed final draft.

Author roles: M.J.A.R. serves as Chief Science Officer at PEPFAR; R.B. serves as Principal Deputy Assistant Secretary at PEPFAR; M.D. is a program manager at PEPFAR; H.C. serves as Senior Advisor for Global Health Security in the Bureau of Global Health Security and Diplomacy; M.B. is PEPFAR's lead for Public Health Systems at PEPFAR; T.M. leads climate change and health at INS in Mozambique; J.N. is Ambassador at Large and serves as PEPFAR's Global AIDS Coordinator.

Conflicts of interest

There are no conflicts of interest.