As we exit a summer of heatwaves, changes to our climate feel very immediate. Many of us will have felt the impact of the high temperatures on our health, from difficulties sleeping to lethargy and headaches. But the intersection between climate change and health goes far deeper.

Climate change is already affecting health worldwide: it both amplifies existing health problems and creates new ones. The effects are direct (eg, heatwaves, flooding) and also indirect (eg, disruption of medical supply chains, increased risk of viral contamination of blood donations, food and water insecurity). Notably, climate-induced changes are not felt equally, with the greatest impact often falling on vulnerable populations such as those with pre-existing chronic health conditions, the young and elderly, pregnant women and low-income communities. The impact also varies based on factors such as geography and occupation.

Clearly, climate change is no longer simply an environmental challenge, but rather a growing clinical and public-health challenge. A challenge that is already evident in clinics today. While tackling the health threat posed by increasing environmental pressures clearly requires broad-based action, what role does the pharmaceutical sector have to play?

Heat is one of the greatest climate-related threats to health, with data from the World Health Organization showing that temperature-related mortality has increased significantly over the past decades, and the prediction is for this to worsen in the future. Rising temperatures affect health in other ways too, from increasing the risk of preterm births, exacerbating cardiovascular and kidney disease, to potential worsening of the severity of allergies due to longer pollen seasons and changes in pollen production.

Rising temperatures, together with other climate-related changes, are also influencing the spread of infectious diseases. Warming trends are linked to an increased risk of tick-borne conditions such as Lyme disease as well as leading to changes in the distribution of such diseases, with more cases being reported at higher altitudes and latitudes. Similar changes are also predicted for other infectious diseases such as dengue.

Changes in temperature can heighten the risk of food-borne diseases too, by creating more favourable conditions for bacterial growth.

Air pollution provides perhaps the clearest illustration of the relationship between environmental and human health. Fossil-fuel combustion is a major driver of both climate change and air pollution, while a changing climate can itself worsen some forms of pollution, including through heat-related increases in ground-level ozone and wildfire smoke. The health consequences are substantial: air pollution is associated with premature mortality and adversely impacts respiratory and cardiovascular disease, cancer, diabetes and neonatal outcomes.

Earlier I described an intersection between climate change and health, but perhaps a more accurate description would be a vicious circle. By way of a simple, everyday example, heatwaves and air pollution tend to lead people to reduce their physical activity, which in turn is not good news for staying healthy and nor is it good for the climate as it means we are more likely to jump in the car versus cycle to work. To take a bigger picture example, climate change increases the burden of disease and puts additional pressure on health systems; healthcare then has its own environmental footprint.

A key action all individuals and organisations can take to improve the future of global health is to reduce our environmental footprint. But for those of us within the pharmaceutical sector, this is not simply a question of environmental responsibility. Climate change has the potential to change the disease landscape, influence patient needs and place new pressures on healthcare systems.

The pharmaceutical sector has an opportunity to anticipate changing health needs brought about by increasing environmental pressures and shape pipelines and scale production accordingly, consider how medicines can help patients manage climate-sensitive conditions, support vulnerable patient populations and help tackle health inequalities.

Surprisingly, despite the profound implications of climate change for human health, engagement across stakeholders appears to be declining. The pharmaceutical sector is ideally positioned to add its voice to those of others in raising awareness of climate change as a health emergency and communicating the health benefits of climate action. Indeed, would making climate change a health story help drive greater action?

Emma Kenny is CEO of the Healthcare Communications Association and a communications consultant