A new book chronicles the science of life in the air
Carl Zimmer unspools the history of aerobiology
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In the 19th century, tuberculosis surged through Europe in a deadly epidemic. A new book recounts how aerobiology, the study of life in the air, illuminated the disease’s airborne transmission.
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Air-Borne
Carl Zimmer
Dutton, $32
On March 10, 2020, 61 choir members rehearsed in a church hall in Skagit County, Wash. As they sang, a microscopic germ wafted through the air. Before the month’s end, 58 members were infected and five fell gravely ill. Across the United States, the virus wreaked havoc. Within weeks, thousands of people died, schools and businesses shuttered and 700,000 people lost their jobs.
Many scientists determined in 2020 that the coronavirus spread through the air, but it would take public health agencies months longer to acknowledge that. The Skagit County superspreader event helped the World Health Organization and the U.S. Centers for Disease Control and Prevention to consider the airborne transmission of COVID-19. But to this day, some scientists believe the delay in calling the virus airborne was a mistake — one that stalled vital public health measures and allowed the disease to spread faster. In his new book, Air-Borne, science journalist Carl Zimmer roots the “mistake” in the past of a historically neglected field: aerobiology, or the science of airborne life.
Zimmer begins his chronicle in the 19th century with Louis Pasteur‘s summit up a towering glacier in the French Alps. As part of a grand experiment, the microbiologist tipped a glass chamber to the sky, snared life and proved that microscopic germs floated in the air. Pasteur’s discovery inspired generations of scientists to look for airborne life themselves, including pathologist Fred Meier, who stuck Petri dishes out of various aircraft and ultimately named the field.
Through the stories of Pasteur, Meier and dozens of other scientists, Zimmer seamlessly weaves together centuries of aerobiology science. He richly humanizes the characters with honesty and complexity, simultaneously highlighting the publicly revered and the unsung. His pithy, punchy and accessible language gives life to glamorous experiments, like those conducted from hot-air balloons, as well as unassuming ones run in university basements.
But aerobiology is more than science-laden joyrides through the sky. The field was mired in humankind’s darkest moments, which Zimmer brings out of the shadows and into the light. Aerobiologists were central to debates on how life-threatening diseases like the Black Death, cholera and tuberculosis spread. And while some scientists worked to fight airborne infections, others committed to creating them, Zimmer writes. During World War II, the United States was one of several countries to create biological weapons. Some U.S. researchers helped build an arsenal of deadly germs and spores to potentially use against the nation’s enemies. For years after the war, aerobiology remained shrouded in secrecy and was largely ignored by public health officials. It wasn’t until COVID-19 that this began to change.
Readers will end the book with a better understanding of just how high life can fly and how far public knowledge of aerobiology has come. It’s a reminder that the current decisions humans make regarding airborne life is informed by a deep history. Zimmer concludes his chronicle with a vision of harmonious coexistence with the life that teems in the atmosphere: “As long as there is life on Earth, it will fly, and as long as we are here, we will breathe.”
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