IAS 2023: Impacts of climate change on the HIV epidemic

Ongoing climate change will threaten the global response to HIV, presenters said at the 12th International AIDS Society Conference on HIV Science, with extreme weather events and other impacts of a warming climate posing unique challenges to people with HIV and the delivery of lifesaving services. The medical community, however, is operating as if climate change is not a pressing concern, presenters said at the conference in Brisbane, Australia. In some cases, the medical community is even creating new forms of pollution, like plastic pollution from increased usage of personal protective equipment, that may affect the environment and can contribute to further climate change.

“Climate change affects the health system, which is the main vehicle for HIV care, from prevention to diagnosis to treatment,” said Renzo Guinto, MD, DrPH, of St. Luke’s Medical Center College of Medicine in the Philippines. Extreme weather events can not only disrupt health systems and inhibit HIV service delivery but can also lead to forced migration, which results in interruptions to HIV treatment adherence and subsequently, poorer health outcomes, greater risk of HIV transmission and drug resistance.

Forced migration can also result in increased risk of acquiring HIV, researchers said. In Poland, where 60% of all Ukrainian refugees currently reside, health care providers are seeing higher rates of new infections among refugees, particularly in women, said Milosz Parczewski, MD, PhD, of Pomeranian Medical University in Poland. “Migrants are more likely to experience worse HIV treatment outcomes,” Dr. Parczewski said. “Stigma and limited access to care are the primary drivers of poor outcomes among refugees,” he added.

Food insecurity resulting from prolonged droughts, floods and other extreme weather events not only contributes to poor health outcomes for people with HIV but can also lead to risky sexual behaviors, like transactional sex, that increase the risk of HIV infection, said Sindhu Ravishankar, MPhil, of the International Association of Providers of HIV Care.

In addition to extreme weather events, drought, water salinization and other immediate impacts of climate change, Dr. Guinto said, there are also more long-term, chronic impacts that would pose unique threats to people with HIV. The spread of climate-sensitive vector-borne infectious diseases like dengue, malaria, Zika and chikungunya, among others, may interact with HIV outcomes and increase risk of co-infection, he said.

There may also be a rise in invasive fungal infections among people with HIV, Nathan Ford, PhD, MPH, of the World Health Organization said. Warming temperatures are likely to result in changes in environmental niches and the distribution and virulence of fungal infections including cryptococcal meningitis and histoplasmosis — already leading causes of death among people with HIV. Currently, cryptococcal meningitis leads to 19% of AIDS-related deaths, Dr. Ford said, and while there is a treatment, it remains unaffordable in most countries with high HIV prevalence.

While the global incidence of histoplasmosis is currently unknown, Dr. Ford said, mortality rates for people with HIV range between 21% and 53%. “The burden in Latin America is equivalent to or greater than TB,” he said, which remains the leading cause of death among people with HIV.

Talaromycosis is a leading cause of HIV-associated deaths in China, Thailand and Vietnam, with the incidence increasing between 30% and 73% during rainy months in those countries.

“Persistently higher temperatures at higher latitudes expand the geographic ranges of known fungal pathogens,” Dr. Ford said. Strengthening One Health approaches and better understanding the spread of fungal infections is key, he noted, as well as strengthening surveillance of such pathogens along with treatment and care for communities with HIV.

Health care providers “need to start reimagining the health care we provide,” Dr. Guinto said, considering the changing climate. Moving forward, climate smart health care should be a priority, he added, including lowering carbon emissions from the health care sector and building resiliency into health systems.