Planetary Health: A Global Health Emergency Under International Law?

[Alexandra L Phelan is a global health lawyer, Senior Scholar at Johns Hopkins Center for Health Security, and an Associate Professor (PAR) in the Department of Environmental Health and Engineering at Johns Hopkins Bloomberg School of Public Health.]

In October 2023, editors from over 200 medical journals published a call for the World Health Organization (WHO) to declare the environmental crisis of climate change and biodiversity loss a global health emergency.

Climate change is the greatest threat to human global health. It impacts health through multiple pathways, directly – such as through extreme weather events like storms, heat waves, and wildfires, and air pollution – as well as indirectly – through human and natural systems that increase the risk of inter alia food and waterborne diseases, famine, and infectious diseases, including pandemics. Biodiversity is critical for functioning of ecosystems fundamental to human health, including clean air and fresh water, as well as limiting the risk of disease and stabilization of the Earth’s climate. Both climate change and biodiversity loss disproportionately impact already vulnerable populations and historically marginalized groups. As the editorial notes, the science-policy platforms for both climate change (the Intergovernmental Panel on Climate Change – IPCC) and biodiversity (the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services – IPBES) have stated that these issues must be treated as “parts of the same complex problem” to “avoid maladaptation and maximize the beneficial outcomes”. Ensuring planetary health by mitigating climate change and preventing biodiversity loss, while adapting to the damage already experienced, is an urgent global crisis requiring immediate action. It is indeed a global health emergency.

The editorial proposes that the WHO “should declare the indivisible climate and nature crisis as a global health emergency”. The editors appear to be referring to the power under the International Health Regulations (2005) (IHR) – a legally binding treaty with 196 States Parties – to determine a Public Health Emergency of International Concern (PHEIC). However, there is legal nuance to this call, as well as an inherent challenge to the use of this power for planetary health issues. 

Firstly, the editorial identifies WHO as responsible for declaring a PHEIC, when the regulations are clear to specify the Director-General, acting on the advice of an Emergency Committee. There are political realities in this difference, as well as procedural, requiring first the convening of an Emergency Committee of experts to assess and advise the Director-General whether the criteria have been met. This is not a fatal issue to the call for a global health emergency declaration but clarifies that the call should be for the Director-General to convene and Emergency Committee on this issue.

More saliently, the editorial broadens and blurs the criteria for a PHEIC, which are essential for assessing whether climate change and biodiversity loss could be determined a global health emergency. Under Article 1 of the IHR, a PHEIC is defined as (1) “an extraordinary event” which (2) “constitute[s] a public health risk to other States through the international spread of disease” and (3) “potentially require[s] a coordinated international response”. The criteria used in the editorial refer to “three preconditions” to an event being declared a PHEIC, namely that the event “is serious, sudden, unusual, or unexpected; carries implications for public health beyond the affected state’s national border; and may require immediate international action”. These requirements are a blurring of the defined criteria under Article 1 with States Parties’ obligations to notify a “potential” PHEIC, under Article 6 and Annex 2 of the regulations which ask States Parties to assess inter alia whether an event poses a serious public health risk and is unusual or unexpected. “Extraordinary” is not defined by the IHR, and it is feasible that a good faith, ordinary meaning interpretation (per Article 31(1) of the Vienna Convention on the Law of Treaties), could include “unusual or unexpected” (for example, the Oxford English Dictionary defines extraordinary as “of a kind not usually met with; exceptional; unusual; singular”). 

The remaining criteria are also broadened to public health implications beyond the narrow tailoring of Article 1 to the “international spread of disease”. This is particularly relevant as it is derived from the WHO constitutional head of power under which the IHR were adopted. Article 21 of the WHO Constitution empowers the adoption of regulations concerning “(a) sanitary and quarantine requirements and other procedures designed to prevent the international spread of disease”. What is important is that climate change and biodiversity loss absolutely pose a public health risk through the international spread of disease, from increased or changing geographic spread of cholera, dengue, malaria, influenza, and novel emerging infectious diseases. The fact that climate change and biodiversity loss are of such a scale that they do even more than this criterion does not leave said criterion unfulfilled. Rather it is a bucket that is well and truly overflowing. And here lies the rub. The IHR do define “event”. An event is “a manifestation of disease or an occurrence that creates a potential for disease”. In a broad reading, climate change and biodiversity loss are both occurrences that create potential for disease. A narrow approach would look to each outbreak, caused or exacerbated by climate change, as the relevant occurrence for a PHEIC declaration. The challenge here is the dearth of climate-health attribution science, which is not produced in a sufficiently timely manner for public health response. There is no comparative precedent for determining climate change and biodiversity loss a PHEIC. However, PHEICs that have required broad interpretations of the criteria – such as the ongoing polio PHEIC – have been controversial. 

The largest question that looms is – so what? What would happen if a PHEIC determination were made? There is no release of funds, no sudden shift in the global governance architecture or new legally binding obligations on states parties. The main power would be the ability of the Director-General to issue temporary recommendations to States Parties, which are non-binding. However, the Director-General also has a power to make standing recommendations where deemed “necessary and appropriate for a specific public health risk”. But the “so what” question looms for any and all PHEICs, and the normative importance of an emergency declaration cannot be understated. When I wrote my doctoral dissertation on this very subject, I argued that “Failure to treat climate change as any less than a public health emergency of international concern is an intergenerational failure to protect the health of the world and its most vulnerable populations.“ 

So what should happen?

The Director-General should consider convening an Emergency Committee, comprised of climate change and health experts, as well as with relevant international law expertise. Under the IHR, the Director-General can receive reports of events from non-state actors, such as a call to action from 200 medical journal editors, as well as the vast array of IPCC and IPBES reports. 

It is vital that global health scholars engage global health lawyers, expert in the IHR, when using it, lest their critical arguments get caught up by devolution into legal technicalities. There is a real risk that any Emergency Committee convened could descend into similar if appropriate legal expertise is not also included in the room.

Secondly, separate to this specific call, the WHO should mainstream consideration of the role of climate change in health emergencies by tracking potential climate and biodiversity loss-attributable factors in health emergencies. 

Thirdly, the IHR are also currently undergoing a significant review process. This is a critical opportunity to assess whether the IHR are fit for purpose given systems level challenges like climate change and biodiversity loss, such as definitional changes or amendments to Annex 2.

Finally, while separate to the PHEIC determination process, the ongoing negotiations for the pandemic treaty must more boldly consider obligations relating to climate change and biodiversity loss as upstream drivers of pandemics. Member States must lead the charge in moving climate change beyond preambular language and commit to obligations that strengthen cohesion between international environmental law and global health law. Under the Bureau’s draft released in June, a proposed Article 5 required countries to commit to “strengthening synergies with other existing relevant instruments that address the drivers of pandemics, such as climate change, biodiversity loss”. However, in the latest negotiating text released on 16 October 2023, climate change has been relegated to a subset of One Health and biodiversity loss is completely missing. This is a major regression that should worry all who work in planetary health. 

There is a real risk that in focusing on whether planetary health threats can or should be declared PHEICs, we miss the forest for the trees. Climate change and biodiversity loss are global health emergencies. We must use all the tools we have available, while crafting more, for urgent action.