At the time of writing, many people around the world are feeling the pain, disruption, and devastating health consequences driven by climate change. The world has been shocked by the widespread flooding in Europe and the consecutive catastrophic hurricanes in North America. Yet far less attention is given to the impacts of climate change in places where Médecins Sans Frontières (MSF) works, such as Central African Republic, Chad, Côte d’Ivoire, Democratic Republic of Congo, Myanmar, Niger, Nigeria, and South Sudan. In 2024, these populations have likewise been affected by devastating floods, many of them not for the first time.

Although immediate impacts like injury, displacement, and limited access to healthcare may be similar worldwide, the compounding crises that follow and the capacity to recover from these vary significantly. Individuals in low-resource and humanitarian settings face significant health threats while contributing the least to global emissions. These regions are often vulnerable to climate hazards and possess low adaptive capacity, increasing people’s susceptibility to the negative impacts of climate change.

In this brief, drawing on evidence from indicators in the 2024 report of the Lancet Countdown on Health and Climate Change, MSF teams present examples of how climate change and environmental degradation are making provision of assistance more difficult by amplifying health and humanitarian needs and by further complicating interventions. It also highlights activities that respond to the climate crisis using a three-pillar approach: mitigating MSF’s environmental footprint, adapting healthcare delivery and emergency response to the current and future realities of climate change, and advocating for those impacted.

The complexity of climate change and environmental degradation, coupled with highly politicised and siloed global response efforts often make it insufficiently clear to health and humanitarian implementing partners that every issue is part of a continuous process, where each component informs the others. In this brief, MSF staff outline six focus areas where teams are engaged in developing environmentally-informed health and humanitarian interventions, emphasising their interdependence, and how failure to act on one issue not only impedes progress on that specific component but also affects the entire sequence of subsequent actions.

There is a need for access to clean potable water worldwide. However, almost every source of surface water in Guatemala is contaminated. This study assesses the potential exposure to water contaminants in proximity to Medecins Sans Frontieres's (MSF) chronic kidney disease clinic population in La Gomera, Guatemala during wet and dry seasons. Five municipal wells and four artisanal wells (servicing approximately 18.9% of La Gomera) were selected for their proximity to MSF La Gomera clinic to determine the presence of coliforms, physicochemical parameters, heavy metals, and pesticide residues. Water samples were collected over 3 consecutive days during La Gomera's wet season and again during the dry season. Wet season 2022: Total coliforms and Escherichia coli exceeded the acceptable limits for several artisanal wells but were not detected in municipal wells. Mercury and arsenic were detected in all wells during at least one sampling period. Dry season 2023: Total coliforms exceeded the acceptable limits for all wells and E. coli was detected in all four artisanal wells. Lead and arsenic were detected in all wells. Our results suggest that water from artisanal wells does not meet COGUANOR or WHO microbiological criteria for human consumption.

Cigarette butts (CBs) have serious harmful effects on the environment and living organisms despite their small size. This research aims to investigate the abundance, densities and pollution status of CBs in Cox's Bazar Sea beach. The survey was conducted between 11 a.m. and 5 p.m. in February 2023, during the peak season of the year. A total of 13,988 CBs were collected, and the mean density was 0.388 m^-2 and ranges from 0.195 m^-2 - to 0.689 m^-2. The mean CBPI value was 7.78, which showed the "high pollution" status. According to CBPI analysis, 25 %, 41.67 %, 16.67 %, and 16.67 % were "severe pollution", "considerable pollution", "high pollution", and "pollution" status, respectively. From HII values, 91.67 % beach fell within the "Class III" category, indicating abundant toxic CBs in the study area. A total of 13 brands were identified, of which Derby (19.31 %), B&H (18.54 %), and Star (11.26 %) were more abundant brands. These findings from this study aim to increase awareness of the harmful effects of cigarette butts discarded intentionally or unintentionally by smokers.