Covid-19—a rehearsal to build a greener and healthier society

Environmental crisis and health in covid-19 context

Although human health improved substantially between 1950 and 2010, this gain was accompanied by global environmental degradation from climate change, loss of biodiversity, and reactive nitrogen and phosphorus being dumped on land and introduced into oceans and waterways. All of these threaten human health and the ecosystem services on which we depend.5 By tackling climate change, reducing the degradation of our natural environments, and building climate resilient health systems, we reduce the risk of emerging zoonotic diseases, one of many health threats. However, only half of the countries surveyed by the World Health Organization have national climate and health plans.6 The Carbon Disclosure Project reported that two thirds of cities surveyed are concerned that climate change will overwhelm their public health infrastructure.7

Climate change affects everybody, but some population groups are more vulnerable than others (box 1). The effect of climate change intersect with other societal changes—for example, population ageing and urbanisation. Vulnerabilities will vary in different places.

The velocity and extent of climate change challenges the global health gains made over recent decades.89 People who are vulnerable may be susceptible to relatively small changes in climatic conditions and their consequences.10 Two examples of health risks needing higher priority in climate change adaptation and mitigation that may be particularly relevant in the covid-19 context are heat related mortality and respiratory diseases associated with air pollution.

Many different population groups are at risk of exposure to increases in temperatures, more frequent heat waves, and air pollution (box 2). Small children may be particularly vulnerable to the effects of climate change as their bodies respond differently to harmful exposures, they lack control over the environment, and they depend on care and protection from adults. Children’s behaviour may also expose them to risks.10 However, older adults have been exposed to air pollution from childhood and throughout their life, driven by fossil fuels and made worse by rising temperatures. Being exposed in childhood is a particular risk as the lungs are developing. It may lead to reduced lung function, and over time increase the risk of heart attacks and stroke.10

In the context of covid-19, health challenges of already existing environmental and climatic change means a converging risk for older people, increasing the risk of morbidity and mortality due to cardiovascular and respiratory disease. The increased susceptibility may be explained by a lower reserve capacity physiologically, an immune system with a slower response, and a slower metabolism. Increased vulnerability may be related to poorer physical health, immobility, being in hospitals and nursing homes, and some commonly used medications.10

Potential underestimation of health risks related to heat means many more people are likely to be affected.10 The Lancet Countdown report on climate change and health reported that heatwave exposure among older people was at a record high in 2019.7 With prevailing policies, the world is projected to be up to 4°C warmer than in pre-industrial times by the end of the century,14 increasing the risks to health in such a way that they are difficult to predict.

Environmental degradation also has a more direct connection to covid-19. Most recent emerging infectious diseases—and all those responsible for recent pandemics, including HIV/AIDS, SARS, and Ebola—have jumped from wildlife to humans, and the evidence suggests that covid-19 has done the same.15 The conversion of natural habitats to human influenced ecosystems is recognised to increase the risk of new zoonotic disease in humans.16 More generally, ongoing human damage to the natural environment creates a global commons challenge: the total damage is no individual’s problem but each individual contributes. There seems to be an appalling lack of understanding of the systemic risks being created in the longer term.

Climate and other environmental changes are consequences of past development pathways. Five years ago, when publishing the planetary boundary framework,17 Steffen and colleagues set out a safe operating space for humanity, stressing the need for a new model for continued development of human societies that maintains a resilient and sustainable earth system. If such a model is accompanied by changes in ecosystems and socioeconomic pathways, it may allow us to identify interactions that could substantially alter the burden of climate sensitive health outcomes, burdens for which health systems will have to be prepared.

The development choices made today will affect how the future looks.1819 Covid-19 is an opportunity to reflect on pathways for moving forward to be better prepared for the next pandemic and build the resilience needed to be able to make a real difference for current and future generations. In healthcare, there is a willingness and readiness to take large and rapid steps to cure acute illness. But there is less willingness for the slower work of preventing illness, even when it is supported by robust evidence and the human and economic benefits would be much greater over both the short and long term. This is illustrated by the slow progress in efforts to control the epidemic of tobacco related disease (box 3).

There is an obvious parallel here between the determination to prevent, handle, and treat covid-19 in the short term and the lack of commitment to decrease environmental and climate degradation and change, which is introducing more severe, major risks in the medium to long term.

Natural experiment

The covid-19 pandemic can be viewed as a natural experiment, showing that social change is possible with rapid cohesive international action, priority setting, and mobilisation of financial resources. Government lockdown policies to prevent the spread of covid-19 reduced travel, industrial production, and energy generation, which in turn decreased the greenhouse gas emissions that drive climate change and the presence of air pollutants. In April 2020, daily global CO₂ emissions were 17% below the mean level in 2019, although levels rose again once restrictions were released.22 A recent estimate from the Global Carbon project suggested a 7% fall in global CO₂ emission from fossil fuel and industry for 2020.23 Despite this, Earth overshoot day—the date when nature’s budget for the year is exhausted by humanity—was reported on 22 August 2020.24

After the global financial crisis in 2008-09, CO₂ emissions rapidly rebounded, mainly from large emission growth in emerging economies, a rapid return to earlier levels of emission growth in developed economies, and an increase in fossil fuel carbon intensity.25 The global community should learn from this and design covid-19 recovery plans that protect vulnerable groups, mitigate climate change, focus on meeting temperature targets set in the Paris agreement, reduce air pollution, increase the resilience of health systems, and strengthen opportunities for green development.26

With regard to climate change, solid evidence is available to guide a planned social change with “green” innovations and use of green technology as part of economic recovery. An immediate increase in transport and travel can be expected after the pandemic, but this needs to be based on energy sources that do not contribute to accelerated climate change. This will not happen without better public policy. Global subsidies for fossil fuel consumption increased in 2016-18 by 50%,27 wasting taxpayers’ money and driving up air pollution and carbon emissions. A substantial change can be achieved by governments switching subsidies to support the consumption and development of green energy and technology.

During the covid-19 pandemic researchers from many disciplines quickly joined forces to build knowledge and find solutions. Scientific journals from a wide range of disciplines have given high priority to publishing articles related to covid-19. A similar combination of forces will be important to deal with future global challenges.

Critical global health leadership and action at all levels

Global health challenges require global leadership in which nations exchange information and strengthen cooperation. The covid-19 pandemic has once again shown the importance and need for global governance in meeting health challenges.

WHO has had a vital role in the covid-19 pandemic. The organisation also had an important role in the eradication of wild polio from the African continent in 2020, which is one of the largest public health successes since the eradication of smallpox. WHO now needs the support of member states to strengthen its ability to deal with future pandemics and health crises, giving it a broader mandate in collaboration with other UN environmental and development agencies. WHO’s leadership in counteracting the environmental and climate crises is essential because, like covid-19, it requires short and long term policies, monitoring systems, and coordinated responses from national governments, the business sector, and the society at large.

The International Monetary Fund (IMF) has also had a key role during the pandemic, supporting financial order in member countries. Raising funds has not been the problem. Governments around the world in a few months deployed around $10tn to respond to the pandemic.28 They now have to invest continued funding wisely, putting green solutions at the forefront. The World Bank will also be important in supporting post-pandemic economic development and social progress in low and middle income countries. International solidarity, global collaboration, and global governance through our UN, development, non-governmental, and other organisations will be essential. Weak international partnerships reduce confidence and trust, resulting in fewer solutions and making it unlikely that the sustainable development goals will be achieved.

Climate change will affect the ability of health systems to function effectively, particularly when climate extremes are combined with existing and emerging health challenges, including outbreaks of infectious disease. Covid-19 has highlighted weaknesses in health systems and put a spotlight on inequities that have long persisted but received insufficient attention. Without prompt and effective climate change action, taking vulnerabilities and inequities into consideration, the problems are projected to worsen considerably.810

Throughout the pandemic, national decision makers have proved willing to make decisions with far reaching consequences. We now have to make use of this crisis and implement actions to protect people and the planet. The commitments for sustainable development are a responsibility for decision makers at all levels. Action now will improve the health of current and future generations.