Climate crisis could cause 'catastrophic harm' to human health, 200-plus medical journals warn

More than 200 medical journals are calling on the World Health Organization to deem two overlapping environmental crises — climate change and biodiversity loss — as a global health emergency, while warning of the potential for "catastrophic harm" to human health.

In the co-ordinated editorial published on Wednesday, a team of authors outlined the dire impacts linked to rising temperatures, extreme weather events and the loss of wildlife. 

The world's health-related environmental challenges are now severe, the group wrote, from the spread of infectious diseases, to the rise of waterborne infections, to the health impacts of air pollution. Changes in land use, for instance, have forced "tens of thousands of species into closer contact," increasing the exchange of pathogens and fuelling the emergence of new diseases.

"The climate crisis and loss of biodiversity both damage human health, and they are interlinked," said lead author Kamran Abbasi, editor in chief of the British Medical Journal, in a statement.

"That's why we must consider them together and declare a global health emergency. It makes no sense for climate and nature scientists and politicians to consider the health and nature crises in separate silos."

The authors are now calling on the WHO to declare both issues a global health emergency at or before the next World Health Assembly in May 2024, calling it a "dangerous mistake" to treat them as separate crises.

The editorial dropped as world governments are preparing for major climate talks, with the next United Nations Conference of the Parties (COP) on climate change happening later this year, and a COP on biodiversity scheduled for 2024.

Richard Smith, chair of the U.K. Health Alliance on Climate Change, which co-ordinated the editorial, told CBC News the global situation is getting more and more desperate.

Record-breaking heat waves, along with extreme fires and storms, are just a few of the climate challenges currently unfolding in places like Canada and the U.K., he said. 

"But these are still comparatively mild with what's going to be happening in just a few years' time if we don't drastically change things," Smith added.

"Many people have argued that we need to think about this in the way we prepare for a war: suddenly everything has got to give way in order to tackle such a serious problem."

The WHO has clear stipulations, however, for what constitutes a public health emergency of international concern (PHEIC).

The organization's international health regulations describe it as "an extraordinary event which is determined to constitute a public health risk to other States through the international spread of disease and to potentially require a co-ordinated international response."

Typically, that also refers to events which are "serious, sudden, unusual or unexpected."