In October 2023 over 200 health journals published an editorial directed to leaders and health professionals, demanding recognition that “climate change and biodiversity loss” are “one indivisible crisis”. The authors use their platform to highlight the importance of responding to this “global health emergency” in a coherent way to protect health and avert “catastrophe”.  

Nature in crisis  

The authors reflect that our current approach is to respond as if the climate crisis and nature crisis “were separate challenges”.  

“This is a dangerous mistake.” 

They refer to the UN Conference of the Parties (COP) on climate change and the COP on biodiversity, which will be held in different locations in different years, suggesting that the “research communities that provide the evidence” are “unfortunately largely separate”. However, when united in a workshop in 2020 they concluded that “climate and biodiversity” are “parts of the same complex problem”.  

Thanks to the development of the concept of “planetary health”, health experts now understand that the natural world is “one overall interdependent system”. Within this, damage to a “subsystem” can trigger “feedback” to damage another. An example of this feedback is the link between droughts, wildfires, or floods, which destroy plant life and lead to soil erosion, thus inhibiting carbon storage and encouraging “global warming”. 

“Climate change is set to overtake deforestation and other land use change as the primary driver of nature loss.”  

Despite this, “nature has a remarkable power to restore”. Thanks to natural regeneration, deforested land can “revert to forest”. Marine phytoplankton can “turn over one billion tonnes” of photosynthesising biomass in just over a week. Importantly, the authors recognise that “indigenous peoples’ approaches” to land and sea management play a “particularly important role in regeneration and continuing care”. Although attention to one subsystem can improve another, actions must be sensitive to the delicate dependence of subsystems: planting forests with a specific tree can extract carbon dioxide from the air but damage biodiversity.  

A human problem 

The consequences of the climate crisis and the nature crisis are human, the authors claim. 

“This indivisible planetary crisis will have major effects on health as a result of the disruption of social and economic systems – shortages of land, shelter, food, and water, exacerbating poverty, which in turn lead to mass migration and conflict. Rising temperatures, extreme weather events, air pollution, and the spread of infectious diseases are some of the major health threats exacerbated by climate change.” 

Even if global warming can be limited to 1.5°C above pre-industrial levels, the authors predict “catastrophic harm to health” in the destruction of nature.  

Work to be done 

The authors recall the 2022 biodiversity COP agreement that 30% of the world’s land, coastal areas, and oceans should be effectively conserved and managed by 2030.  

“Many commitments made at COPs have not been met.” 

Consequently, ecosystems have been “pushed further to the brink”. This “brink” is dangerously close to “tipping points – abrupt breakdowns in the functioning of nature”. So, what do they suggest? The editorial demands a WHO declaration of a global health emergency. It highlights that the three preconditions for a public health emergency of international concern have been met; climate change is “serious, sudden, unusual, or unexpected”, with “implications for public health beyond the affected state’s national border” and a need for “immediate international action”.  

“We call for WHO to make this declaration before or at the 77th World Health Assembly in May 2024.”  

However, declarations must be followed by actions, and the authors state that the COP processes should be “harmonised”. For a start, “respective conventions must push for better integration of natural climate plans with biodiversity equivalents”.  

“Health professionals must be powerful advocates for both restoring biodiversity and tackling climate change for the good of health. Political leaders must recognise both the severe threats to health from the planetary crisis and the benefits that can flow to health from tackling the crisis.” 


“But, first, we must recognise this crisis for what it is: a global health emergency.”  

What do you think about the commentary in these journals, and what action should be taken from a global health perspective? In particular, how can vaccines factor into crisis management? If this is an area of interest for you, why not check out our interview with Dr Alex Dehgan for further insight? For more, remember to subscribe to our weekly newsletters.