Climate change fuelling spread of deadly fungal infections, study warns

The climate crisis is rapidly expanding the global reach of life-threatening fungal infections, with rising temperatures enabling dangerous species to thrive in new regions, according to a new study.

Two major fungal pathogens – Aspergillus fumigatus and Aspergillus flavus – are set to spread faster across new parts of Europe and other regions as warming continues, researchers warn.

The findings raise fresh concerns about the growing health burden posed by fungal diseases, which remain understudied compared to other infectious threats.

Using climate modelling, researchers from the University of Manchester found that A fumigatus, which causes aspergillosis, a severe and often fatal lung infection, could expand its geographical range by 77 per cent by 2100 under high-emission scenarios. The shift would potentially expose an additional nine million people across Europe to the fungus.

Meanwhile, A flavus, which infects crops and produces carcinogenic aflatoxins, is projected to spread over 16 per cent more land globally. Its spread threatens both human health and food security, particularly in regions already vulnerable to climate stress.

“Changes in environmental factors, such as humidity and extreme weather events, will change habitats and drive fungal adaptation and spread,” Dr Norman van Rhijn, one of the authors of the study, said.

The findings come amid growing concern that fungal infections – long neglected by global health policy – could spark a major public health crisis in coming decades.

Unlike bacterial infections, fungi are harder to treat and resistant to many existing drugs. Despite the threat, less than 10 per cent of the world’s estimated fungal species have been described.

In 2022, the World Health Organisation listed fungal pathogens among its top priority threats for the first time. Despite this, fungal research remains underfunded. In response to the growing risks, the Wellcome Trust has announced over £50 million in funding for fungal disease research over the next year.

“We have already seen the emergence of the fungus Candida auris due to rising temperatures, but, until now, we had little information of how other fungi might respond to this change in the environment,” said Dr van Rhijn. “Fungi are relatively under researched compared to viruses and parasites, but these maps show that fungal pathogens will likely impact most areas of the world in the future. Raising awareness and developing effective interventions for fungal pathogens will be essential to mitigate the consequences of this.”

Experts warn that the spread of fungal infections may also be accelerated by extreme weather events such as storms, droughts and wildfires, all of which can disturb spores and create ideal conditions for fungal proliferation.

While the study found that warmer climates could drive fungal spread across new parts of Europe, some parts of Africa may become too hot for certain fungi to survive.

However, researchers warned that fungi’s resilience, large genomes, and rapid adaptability make them capable of evolving in response to new conditions.

Antifungal resistance is also increasing, driven in part by the widespread use of fungicides in agriculture. Many infections have high mortality rates, and existing antifungal treatments are limited due to toxicity and the biological similarity between fungi and humans.

“Fungal pathogens pose a serious threat to human health by causing infections and disrupting food systems. Climate change will make these risks worse,” Viv Goosens, research manager at Wellcome, said.

“To address these challenges, we must fill important research gaps. By using models and maps to track the spread of fungi, we can better direct resources and prepare for the future.”