Not the Last of Them

I’m seeing two conflicting yet connected visions about the future. One is when journalist David Wallace-Wells says we might be in for “golden age for medicine,” with CRISPR and mRNA revolutionizing drug development. The second is the dystopian HBO hit “The Last of Us,” in which a fungal infection has turned much of the world’s population into zombie-like creatures.

Credit: HBO

The conflict is clear but the connection not so much. Mr. Wallace-Wells never mentions fungi in his article, but if we’re going to have a golden age of medicine, or if we want to avoid a global fungal outbreak, we better be paying more attention to mycology – that is, the study of fungi.

We don’t need “The Last of Us” to be worried about fungal outbreaks.  The Wall Street Journal reports:

Severe fungal disease used to be a freak occurrence. Now it is a threat to millions of vulnerable Americans, and treatments have been losing efficacy as fungal pathogens develop resistance to standard drugs. 

“It’s going to get worse,” Dr. Tom Chiller, head of the fungal-disease branch of the Centers for Disease Control and Prevention, warns WSJ.

A new study found that a common yet extremely drug resistant type of fungus -- Aspergillus fumigatus – has been found even in a very remote, sparsely populated part of China.  Professor Jianping Xu, one of the authors, points out: “This fungus is highly ubiquitous — it’s around us all the time. We all inhale hundreds of spores of this species every day.”

We shouldn’t be surprised, because fungi tend to spread by spores  In fact, according to Merlin Sheldrake’s fascinating Entangled Life: How Fungi Make Our Worlds, Change Our Minds, and Shape Our Futures, fungi spores are the largest source of living particles in the air. They’re also in the ground, in the water, and in us. They’re everywhere.

That sounds scary, but without fungi, we not only wouldn’t be alive, we never would have evolved. Fungi allowed sea-based plants to colonize land, which led to sea creatures moving ashore, which eventually led to us, among other species. Dr. Sheldrake notes that every plant growing under natural conditions has fungi living with it. They help break down minerals in the soil for plants, among other things. 

Without them, we’re nothing.

And that part about taking over animal’s brains, as in The Last of Us, is, in fact, true. For example, they are known to invade ants’ and mice’s brains, causing them to exhibit unusual behavior that gets the animal killed but cause the fungi to spread, which is their goal. As for influencing human’s behavior, the answer seems to be somewhere between “maybe” and “probably.”  If you are a fan of hallucinogenic mushrooms, then the answer is “yes.”

In an interview with The New York Times, Dr. Sheldrake argues: “Mycelium [networks of fungal threads] is ecological connective tissue and reminds us that all life-forms, humans included, are bound up within seething networks of relationships, some visible and some less so.” We can ignore them, we can try to fight them, but failing to recognize how we fit into those networks comes at our own risk.

“Fungi aren’t being given enough thought,” Dr. Peter Pappas, an infectious-disease specialist at the University of Alabama at Birmingham, told WSJ.  Dr. Andrej Spec, an infectious-disease specialist at Washington University, agreed, adding: “In medicine, fungi are an afterthought. We need a paradigm shift.”

Indeed. As WSJ went on to say:

Many medical schools aren’t adequately training aspiring doctors to identify and treat fungal disease, infectious-disease experts said. Some schools dedicate a couple of hours to the topic, those experts said. “Most fungal diseases are taught in medical school as being rare or unusual or some even regional, but we see these on a daily basis,” said Dr. George R. Thompson, an infectious-disease specialist at the UC Davis Medical Center in Sacramento. 

I’m glad that we’re at least realizing the issues that fungi can cause for our health, but I fear we’ll go down the same road we’ve gone down with bacteria.  We discovered they could harm us, then found we could kill them, developing an array of antibacterials that could wipe them out at scale, then proceeded to blithely overuse them.  To late, we eventually realized that, duh, bacteria become resistant to them over time, and, even worse, we need some bacteria.

We’re starting – barely – to recognize the importance that our microbiome plays in our health, but we haven’t significantly changed our medical education or our practice of medicine to recognize that role.  We’re even further behind when it comes to the mycobiome.  If we’re barely teaching how to identify and treat fungal diseases in medical school, imagine how much further behind we are in how to use our fungal companions to bolster our health.

Credit: Anders Nilson/The New Yorker

Immunologist Barney Graham, a central figure in the development of mRNA vaccines, told Mr. Wallace-Wells: “It’s stunning. You cannot imagine what you’re going to see over the next 30 years. The pace of advancement is in an exponential phase right now.”  But, I would argue, if all we do is to build a new array of vaccines and weapons against various microbes, I don’t expect a golden age for our health.

Mr. Sheldrake and others are looking at using, not killing, fungi. They can be used, for example, to create antivirals, to break down pollutants, to create food, to build materials (mycofabrication), and even, as Mr. Sheldrake describes in a new paper, to help us combat climate change through carbon sequestration.  They are not our enemy.  They were here before us, and they’ll be here long after us.

As Dr. Pappas said, we need a paradigm shift.

It’s amazing that we’ve cracked our genetic code, and even more than we’re now able to edit it.  It’s astonishing how we can use imaging to watch our bodies – and even our brains – function in real time, and can use those results to identify problems. It’s exciting that we can use DNA fragments to detect cancers and other illnesses at early stages.  But we’re still stymied as to what a “healthy” microbiome is and how that matters to us, much less how our mycobiome interacts with it, and with “us.”

The fact of the matter is that our concept of “us” is an illusion. We are a network, of our own DNA, cells and processes, and of all the other organisms that coexist with us.  Our health is a network effect; we’re only healthy when that network is in balance.

We’re not getting to a golden age of medicine and biomedical innovation without fungi.