The Last of Us ‘minus the zombie part’: How fungi could become supercharged by climate change

The Last of Us ‘minus the zombie part’: How fungi could become supercharged by climate change

Rising temperatures may cause fungi to be more dangerous to our health, a new study reveals.

While bacteria and viruses are well known drivers of infection and disease, pathogenic fungi have so far only caused minor problems for healthy people.

This is usually because the human body temperature is typically too hot for infectious fungi to survive.

But that might be about to change, researchers at Duke University in North Carolina warn.

This may ring alarm bells for fans of the hit dystopian HBO series, ‘The Last of Us’, in which a heat-adapted fungus takes over humans.

“That’s exactly the sort of thing I’m talking about - minus the zombie part!” says study co-author Asiya Gusa.

What are pathogenic fungi?

Pathogenic fungi are fungi that cause disease in humans and other organisms.

Among the approximately 300 fungi known to be pathogenic to humans, Candida, Aspergillus and Cryptococcus are some of the most well known.

They are currently most dangerous to immunocompromised people who lack the defences to prevent their spread.

How could rising temperatures make fungi more dangerous?

Rising global temperatures are predicted to increase fungal diseases in humans, but they could also make those diseases more serious.

Studying the impact of heat stress on fungi, researchers found that higher temperatures led to rapid genetic changes in the human fungal pathogen Cryptococcus.

Higher temperatures were found to stimulate the fungus’s transposable ‘jumping genes’, accelerating the number of mutations and leading to adaptations in the way the genes are used and regulated.

“These mobile elements are likely to contribute to adaptation in the environment and during an infection,” says Gusa. “This could happen even faster because heat stress speeds up the number of mutations occurring.”

This could lead to higher heat resistance, drug resistance and disease-causing potential, according to the research published in the science journal PNAS.

“This is a fascinating study, which shows how increasing global temperature may affect the fungal evolution in unpredictable directions… One more thing to worry about with global warming,” says Dr Arturo Casadevall, chair of molecular microbiology and immunology at Johns Hopkins University.