On TV, Killer Fungi are a horror storyline. In this book they are real.

BLIGHT: Fungi and the Coming Pandemicby Emily Monosson

There is a scene in Don DeLillo’s novel “White Noise” where the main character reminisces with an ex-wife who was “ultra-sensitive to many things,” as she puts it. “Sunlight, air, food, water, sex,” he says. She doesn’t disagree: “Carcinogenic, y’all.”

Life can be deadly – I found myself slipping into this kind of environmental paranoia while reading Emily Monosson’s disturbing new book, “Blight: Fungi and the Coming Pandemic.” Fungi are everywhere, and they’re having a moment, with documentaries like Louie Schwartzberg’s “Fantastic Fungi” (2019) and books like Merlin Sheldrake’s “Entangled Life” (2020) telling us about all the beneficial things fungi can do – expand our consciousness, clean up oil spills, help trees share nutrients under the forest floor.

Monosson’s book takes the other direction. Like “The Last of Us,” the video game and HBO series that posit a fungal pandemic that turns humans into zombies, “Blight” highlights the decidedly unhealthy things fungi can do: “Collectively, contagious fungi and mold-like pathogens are the most devastating pathogens known on the planet.”

She opens her book with Candida auris, a fungus that has flourished in recent years, making its way through hospitals and infecting patients whose immune systems have already been compromised by other conditions. Fungal infections of the skin are usually not life-threatening; it is when they enter the blood that they can be deadly. Being warm-blooded has afforded humans and other mammals a degree of protection: Most fungi prefer cooler temperatures; we run too hot.

But global warming and medical advances are changing that, says Monosson. Some fungi can evolve to tolerate higher temperatures; she explains how valley fever, caused by fungal spores in the soil of the Southwest, is spreading faster as the climate changes. While organ transplants and cancer treatments are saving lives, they are also creating a growing population of immunocompromised people. “We are living longer and better, but becoming increasingly susceptible to invasive fungi,” Monosson writes. And because fungal cells share some structural similarities to our own, it’s hard to develop drugs that target them without harming us. Amphotericin, an antifungal drug introduced in 1959, has side effects so horrible and potentially deadly that doctors call it “amphoterrible.”

A fungal epidemic among humans is not the main concern of this book, even though it is undoubtedly the one that will catch the readers’ attention. Amphibians, whose body temperature depends on their external environment, are vulnerable to fungal infections; Monosson tells of a collapse in frog populations that began to attract attention in the late 1980s, with a researcher recalling how she would grab a frog and let it die in her hand. (The researcher, writing with a group of other scientists, would later characterize this mass die-off as “the greatest documented loss of biodiversity attributable to a single pathogen.”) The wildlife trade is a particular source of danger, Because unlike livestock, which is tested by governments fearful of infecting the food supply, most exotic pets are not subject to rigorous screening or monitoring, creating what Monosson calls a “fungal pathogen free for all.”

Mold spores are so small and ubiquitous that Monosson, who trained as a toxicologist, envisions how a bat whose wing brushes the floor of a cave can pick up the spore that eventually kills it. Some bat populations in North America have dropped by as much as 90 percent because of white nose syndrome, caused by a fungus that feeds on the keratin in a bat’s skin. Bats tend to get hot just like us, except in winter when food is scarce, and they conserve energy by entering a state of torpor that suppresses their immune system and their body temperature. This provides an opportunity for Pseudogymnoascus destructans, the fungus known as Pd, to get to work.

What ensues in a bat’s hibernaculum or winter quarters is a horror show of sorts, with bat wings covered in so many lesions that they resemble a “moth-eaten sweater” and other fungi feeding on “the dead or dying”. Like any plausible apocalyptic scenario, Monosson suspects this probably started innocently enough – perhaps with a spore of Pd traveling across the Atlantic from Europe in a bit of mud or on someone’s clothes.

But as the title ‘Blight’ suggests, the main victims in this book are plants and trees. The American chestnut, once dominant in North America, was decimated by blight in the early 1900s. Three to four billion chestnuts died within a few decades—no doubt a “frightening” experience, says Monosson, and he recounts a time before Congress passed the Plant Quarantine Act of 1912, when “novelty was more important than the diseases a new plant would And since we humans are notorious for worrying about what might pose a threat to us, Monosson carefully explains how fungal diseases can affect food supplies. caused by a mold but by a water mold.)

Still, we shouldn’t despair, Monosson writes: Half of her book is devoted to what she calls “solution.” Fungi evolve, but so do plants and animals. A recent ‘fat bat’ study found that bats that gain a few extra grams before winter are better able to survive a fungal infection. Monosson describes how some trees have evolved genes that allow them to respond to a fungal spore with “protective cell death,” essentially starving the spore of living material on the side of the tree where it lands so the fungus can’t get very far. But trees also take decades to mature and reproduce in order to pass on those protective genes, meaning a “fast-moving deadly fungus” can surpass “tree time.”

This is where people come in. Some of our interventions were unintentionally harmful; the fungal threat has been aided by agricultural fungicides, which have spurred fungi — including those that can infect immunocompromised humans — to develop resistance. But human ingenuity can also be useful. Monosson, whose previous books include “Unnatural Selection: How We Are Changing Life, Gene by Gene,” says intentionally breeding plants and trees for blight resistance is an old method that can continue to help us. Advances in bioengineering, she adds, have opened up even more possibilities.

But tree time is still tree time. I was touched when I read about Charles Burnham, a retired geneticist who developed a 30-year plan to breed chestnuts for resistance to fire blight. Just over a decade before he died in 1995, at age 91, he helped found the American Chestnut Foundation to further his plan. This was pragmatism in the service of hope: “Burnham knew he was not going to make it.”