New obstacles in HIV prevention and care are emerging as climate change worsens extreme weather events, according to a review published recently in Current Opinions in Infectious Disease. Researchers at the University of Toronto examined 22 current research studies on HIV-related outcomes in the context of climate change and discovered important correlations between extreme weather events and HIV prevention and care. 

Researchers have linked poor HIV preventive results, including decreased HIV testing, to climate change-related calamities like droughts and flooding. Furthermore, these events contribute to increased HIV-risk behaviours, such as transactional and condomless sex, which result in an increase in new HIV infections. "Climate change impacts HIV prevention through several mechanistic pathways," explains main author Carmen Logie, a professor at the Factor-Inwentash Faculty of Social Work (FIFSW) at the University of Toronto and the United Nations University Institute for Water, Environment, and Health. "Extreme weather events inflict structural damage to health-care infrastructure while also increasing migration and displacement, both of which impede access to HIV clinics for prevention and testing. We also detect an increase in HIV-risky practices as a result of climate change-related resource shortages."

The study also found major implications for those currently living with HIV, such as decreased viral suppression, lower treatment adherence, and deteriorating physical and mental health. Extreme weather disrupts healthcare access, making it difficult for people to stick to their treatment plans. "Extreme weather events present new challenges with access to HIV care and treatment adherence," says co-author Andie MacNeil, a PhD student at FIFSW at the University of Toronto. "Multilevel strategies are needed to mitigate the effects of climate change on HIV care, such as long-lasting antiretroviral therapy, increased medication dispensing supplies, and community-based medication delivery and outreach programs." 

The researchers also found big holes in the existing research. For example, there isn't much on specific extreme weather events like hurricanes, wildfires, and extreme heat, or on places like the Middle East and North Africa where climate change is making people more vulnerable and HIV rates are rising. Another major gap is a lack of information of how extreme weather events affect marginalised populations, such as sex workers, drug users, and gender-diverse individuals, and how these effects combine with other forms of stigma. 

Despite the challenges identified in the study, the authors are optimistic that their findings will lead to significant advances in research, policy, and practice. "New HIV programs, like long-acting PrEP, mobile pharmacies and health clinics, and treatments that deal with lack of food and water, may all help to improve HIV care during extreme weather," Logie said. "More research and evaluation are needed to test HIV prevention and intervention strategies that are informed by climate change." "The integration of disaster preparedness and HIV care provides new opportunities to optimise HIV care in our changing climate."