by Arturo Casadevall is a professor of molecular microbiology and immunology at the Johns Hopkins Bloomberg School of Public Health. He has spent four decades investigating how fungi can improve and destroy life as we know it. His new book, What If Fungi Win?it registers how we might overcome the rising threat.
What first got you interested in fungi?
When I was training as someone with an infectious disease [in the 1980s], AIDS was our biggest problem. Patients were not dying from HIV infections [which attack the immune system, leaving it vulnerable to other diseases], they were dying of opportunistic infections – and these were often fungal. This was the first large-scale human fungal crisis in history. When I started working on the medicinal side of fungi, I discovered the wonders of this kingdom.
The award-winning series The Last of Us it charts a world where a fungus triggers the apocalypse. Could that happen?
Improbable, but not impossible. Currently, we do not know of any fungus that can turn a person into a zombie. But there is no question in my mind that we will likely see new and dangerous fungal pathogens emerge in time. In fact, we are already seeing it. So who knows?
Fungi make powerful toxins, so they were considered agents for biological warfare
In your book, you describe the climate crisis as a major risk for fungus that develops over which we have no control. Why is that?
Everything in our environment is affected as temperatures rise; there is no reason to believe that fungi will be an exception. As modern medicine paradoxically creates more people at risk of new fungal infections, evidence is mounting that certain fungi have the ability to unleash new diseases that will harm many others in unseen ways never before.
What if fungi could adapt to higher temperatures? They would jump over our defenses. Will we see a lot more fungal diseases then? That is the fear.
Has this already happened?
Candida auris it was not known to medicine until 2007 when it was found in the ear of an individual in Japan. And then a few years later, in 2010, 2011, 2012, it emerges independently on three continents [South America, Africa and the Indian subcontinent].
So we have a medical mystery. We have an organism for which there was no known cure. One of the things we have suggested is that this may have been the first fungus to overcome our thermal barriers [most fungi cannot survive at 37C degrees, the body’s internal temperature] after adapting to higher temperatures. This is probably the first example of a new fungal disease arising from climate change.
Can fungi be used for good?
Fungi are vital elements to life on earth. They benefit us in foodstuffs – you can’t have wine without fungi, you can’t have fermentation without fungi. They are the source of brand new medicines, such as penicillin and statins. Innovators are using fungi to make vegan leather car seats and building materials. Others are using it to degrade the plastics that fill our landfills. From now on, they may be new sources of content, things that could improve our daily lives.
Could they be used for more sinister ends?
You always worry about engineering organisms for evil. I don’t know that anyone is doing it. But sure [for] a kingdom so large and diverse with so many powerful species that must be on the radar – that it could somehow be used by bad actors. They make powerful toxins, so they were considered agents for biological warfare. Fungi have terrible uses but, in general, the good and potential benefits far outweigh the negatives.
How can they be used for biological warfare?
Many fungi make spores, and the spores are designed to be carried by the wind. Generally when people do biological warfare, they have to change the organism so that it can be spread by air. Well, the fungi come ready to spread in the air.
Could they cause a pandemic?
Humanity has not experienced a fungal pandemic, but other species have. The amphibians are being destroyed by a fungus that has spread to all the continents. So if a fungus can do that to amphibians that have been around for millions of years and have good immune systems like we do, I think it’s rubbish to think that something can’t happen to us. We have a huge blind spot when it comes to the diseases and toxins that fungi can inflict.
What are the biggest challenges in fighting back against fungus?
Because fungi are our closest relatives, it is difficult to find drugs that kill them and do not harm us. Then there is the economic explanation. Many fungal diseases are less common [as others]and if you’re a pharmaceutical company and you’re wondering where to put your money, you often do [make the decision] based on market size. Progress is being made, but we have a long way to go.
Related: ‘The situation has become dire’: bogus scientific papers send research credibility to crisis point
In terms of your own research, what are you most excited about?
It turns out that fungi, most of them, make melanin, the same melanin we have in our skin. This melanin has many properties that can be taken advantage of. For example, melanin is a natural shield against radiation. [It] almost like science fiction, but we are working with NASA collaborators on the idea that melanin from fungi can be used for coating spacecraft.
I’m also excited about some of the progress we’re making in understanding how fungal diseases are caused. If you understand the mechanisms, you may be able to interfere with them – and if you can interfere with them, you can help people.
You spoke out about the rise of falsified research driven by “fraudulent data and bogus science“. How widespread is the problem?
I have been very concerned for a long time that science is not working as well as it should. We’ve done studies that show there was an epidemic of withdrawals. Why is that? Well, we found that there was a significant amount of misconduct involved. That is completely unacceptable.
I look at this almost like an existential problem. If science doesn’t work, it won’t give humanity the tools it needs. And if people lose trust in us [scientists], they are going to cut the funding, and then it will all fall apart. Less funding, less science, less solutions.
The name of the book is What if Fungi Win?. What if they do victory?
I think they won already. And I think if they win, we win.
