The Lancet Countdown to 2025 warns that human-induced climate change is leading to poor health and unnecessary deaths of millions of people annually, mainly due to fossil fuel dependence and rising greenhouse gas emissions[1][2]. Average annual temperatures in 2024 will exceed 1.5°C above pre-industrial levels, increasing the frequency of heat waves, extreme weather events and the spread of infectious diseases[1]. Climate change also negatively affects the availability of food and water, worsens socio-economic conditions and increases the vulnerability of populations[1][5]. However, despite the growing challenges, some countries and companies are reducing their climate commitments, while local and community initiatives are gaining momentum[1][2]. Healthcare systems are increasingly preparing for climate risks; 58% of countries have completed vulnerability assessments and 60% have national health climate change adaptation plans[4]. Positive changes also include a 16% reduction in greenhouse gas emissions from the healthcare sector between 2021 and 2022[4]. The report highlights that action against climate change presents a significant opportunity to improve public health, for example through cleaner air, healthier diets and more resilient health systems, which can save millions of lives[4]. In total, the report tracks 57 indicators that comprehensively assess the link between health and climate change, and calls for rapid and coordinated action at the global level[1][2].