When Fungi Heat Up: How Climate Change Fuels New Fungal Threats
For most of human history, we’ve been protected from fungal disease by one simple fact: our body temperature is too hot for most fungi to survive. But as the planet warms, scientists warn that this natural thermal shield is weakening — and fungi are adapting in surprising ways.
At a recent Duke University symposium, microbiologist Arturo Casadevall (Johns Hopkins) put it simply:
“The thermal barrier is narrowing. Whenever the Earth does poorly, fungi do well.”
So what’s happening inside fungi that lets them survive — and even thrive — in heat? Three new pieces of research provide some answers.
1. Jumping Genes That Create Drug Resistance
A 2020 study by Asiya Gusa and colleagues (Duke University) revealed that in the human pathogen Cryptococcus, heat stress acts like a genetic shock. At body temperature (37°C), transposable elements — also known as “jumping genes” — start moving around the fungal genome.
This jumping creates mutations that:
Break important genes
Alter stress responses
And sometimes make the fungus resistant to antifungal drugs like 5-fluorocytosine or rapamycin
In other words, when fungi get hot, their DNA goes into hyperdrive — rapidly evolving in ways that help them survive inside us.
2. The Enzyme That Helps Fungi Beat the Heat
In 2024, Duke scientist Erica J. Washington and colleagues solved the 3D structure of trehalose-6-phosphate synthase (Tps1), an enzyme fungi rely on during heat stress.
Trehalose is a special sugar that acts like a molecular shield:
Protecting proteins from unfolding in heat
Helping cells manage stress
Supporting energy metabolism
By mapping Tps1 at the molecular level, researchers now see how fungi “gear up” biochemically to handle higher temperatures. Even more importantly, Tps1 may represent a new target for antifungal drugs, since humans don’t use this same pathway.
3. Climate Change: Giving Fungi More Chances to Adapt
The symposium also highlighted the real-world stakes. With more frequent extreme heat days, fungi are getting repeated opportunities to evolve thermotolerance. This could explain the sudden rise of Candida auris, a once-rare fungus now spreading in hospitals worldwide.
Duke’s mycology team also pointed to another concern: post-disaster fungal growth. After Hurricane Helene, researchers sampling flooded buildings in North Carolina found dangerous molds flourishing in drywall and wood — some with relatives known to cause infections in people.
With 3.8 million fungal deaths globally each year (nearly double a decade ago), this isn’t a future problem — it’s already here.
The Big Picture
Put together, these findings show that:
Fungi can rewire their DNA under heat stress (Gusa et al., 2020).
They rely on special enzymes like Tps1 to survive scorching conditions (Washington et al., 2024).
And climate change is giving them more opportunities to practice and adapt (Kirkendoll, 2025).
The same biology that makes fungi resilient in the environment also makes them harder to fight as pathogens. Without vaccines and with only a handful of antifungal drugs, scientists are racing to understand these mechanisms before new fungal diseases emerge.
Conclusion
The message is clear: warming temperatures are reshaping the fungal kingdom, with consequences for human health, agriculture, and ecosystems. By learning how fungi adapt — from jumping genes to protective sugars — researchers hope to develop better treatments and stay one step ahead.
As Casadevall warned, the “fungal apocalypse” imagined in TV shows may be far-fetched. But the rise of heat-tolerant, drug-resistant fungi is not science fiction. It’s science fact — and it’s unfolding now.
