A Century of Microbe Hunters
The endurance of a medical adventure book reveals changing anxieties about public health, from quackery to COVID
ReadAdventurous stories of medical discoveries!
Paul de Kruif’s Microbe Hunters (1926) profiles 13 microbiologists who studied the causes of infectious disease from the 17th century to the early 20th century. De Kruif imagines scientists as heroes of old, who battle with germs “more terrible than fire-spitting dragons.”
Frontispiece: Portrait of Antoni van Leeuwenhoek (1695) by Verkolje, Jan, 1650- and Leeuwenhoek, Antoni van, 1632-1723Science History Institute
Sensational language, invented inner lives
De Kruif made scientific discovery vivid and exciting, sometimes making up emotional reactions or dialogue that never happened. Listen to this passage from Microbe Hunters about Antoni van Leeuwenhoek, the first person to identify bacteria using a microscope in the 1670s.
Microbe Hunters has been republished dozens of times, translated into 18 languages, and adapted for film and stage. Today, copies of the book can be found in cities around the world. It has inspired generations of young readers to become microbe hunters themselves.
Editions of "Microbe Hunters”Science History Institute
Changing editions reveal evolving concerns about public health and connections between medical science and society. Look at the covers of these reprints of Microbe Hunters. What do the cover illustrations suggest about disease and medicine at the time?
The Truth About Syphilis (1922) by Paul H. de KruifScience History Institute
The origins of “Microbe Hunters”
The history of medicine can be seen as a series of struggles over authority: whose ideas about health and the causes of illness should be taken seriously?
Creating “Microbe Hunters”
In the 1920s, Paul de Kruif was frustrated with U.S. medicine. A trained microbiologist, de Kruif accepted the germ theory of disease, which posited that microbes—bacteria, parasites, and viruses—cause illness. Treatments needed to target these infectious agents.
Vaccines for Broken Legs (1922) by Paul H. de KruifScience History Institute
De Kruif spent much of his early career attacking quacks and profiteers peddling alternative treatments, from electronic therapy to cure-all vitamins, drugs, and salves. Journalist Norman Hapgood once praised de Kruif’s writing as “destructively critical rather than constructive.”
Albert Abrams, The Wonder of the West (1923) by Paul H. de KruifScience History Institute
De Kruif’s crusade culminated in a series of magazine articles like those seen here, which attacked practitioners of different stripes for being dishonest or underqualified. As a result of this work, the Rockefeller Institute fired de Kruif, leading him to devote more time to writing.
Paul de Kruif Smoking a Pipe (1944)Science History Institute
When de Kruif began writing Microbe Hunters, he took a new approach. “I have started a new book, this time constructive!” he told his friend H.L. Mencken in 1923. Microbe Hunters would celebrate researchers who valued scientific objectivity above all else.
Clippings of “Microbe Hunters” ReviewsScience History Institute
Initial reactions to “Microbe Hunters”
Many reviewers in 1926 thought the sensational writing style made medical science engaging. But some medical professionals found the collection unscientific. The British edition even excluded a chapter after microbe hunter Ronald Ross threatened a libel suit.
Adaptations
Microbe Hunters’ success inspired adaptions for stage and screen. Yellow Jack was a 1934 Broadway play based on Walter Reed’s work on yellow fever. The 1940 film Dr. Ehrlich’s Magic Bullet dramatized Paul Ehrlich’s discovery of a compound effective against syphilis.
Dinner Party Scene, "Dr. Ehrlich’s Magic Bullets" (1940) by Warner BrothersScience History Institute
The movie’s direct reference to “syphilis” sparked controversy: Americans did not talk about sexually transmitted diseases in polite conversation. Nevertheless, in the 1930s, public health officials expected one in ten people to contract syphilis at some point in their lifetime.
De Kruif’s publishers capitalized on the film’s success. This 1940 Pocket Book edition even changed the title, “to turn the spotlight on Dr. Paul Ehrlich, who is now being immortalized in the magnificent, heart-warming Warner Brothers motion picture.”
Destroyers Syphilis Poster World War II (1940s)Science History Institute
War, syphilis, and magic bullets
Venereal disease (VD) became a more prominent subject of public discussion in the 1940s, as millions of young men were mobilized to fight World War II. Military posters created to fight “VD” villainized prostitutes and warned soldiers that casual sex would harm the war effort.
In 1943, the U.S. Public Health Service released a 30-minute cut of the film called Magic Bullets, preserving the arc of Ehrlich’s syphilis research and the original’s anti-German sentiment. The U.S. War Department showed it to soldiers, hoping to reduce the spread of syphilis.
Cover of 1954 Edition of "Microbe Hunters" (1954) by Paul H. de KruifScience History Institute
Inspiring a new generation
Millions of copies of Microbe Hunters appeared in schools and libraries around the world. It encouraged some young readers to pursue careers in biomedical research, like Carl Djerassi, a creator of the birth control pill, and Nobel Laureate and bacteriologist Joshua Lederberg.
Cover of 1965 Edition of "Microbe Hunters" (1965) by Paul H. de KruifScience History Institute
A love of Microbe Hunters played a crucial role in Roger Karess’s admission to graduate school at Rockefeller University in 1976. Karess went on to research retroviruses, a subject of intense global interest after the outbreak of HIV/AIDS in the 1980s.
AIDS Awareness Brochures and Posters (1987) by Public Health ServiceScience History Institute
“Microbe Hunters” in the age of HIV/AIDS
The successes of vaccination and antibiotics in the decades after World War II made microbe hunting seem less urgent. But the AIDS epidemic in the 1980s brought renewed attention to infectious disease.
ACT UP/PWAC: AIDS Advocacy Groups (1993) by AIDS Coalition to Unleash Power and People With AIDSScience History Institute
As with syphilis in the 1940s, government responses to the AIDS crisis in the early 1980s stigmatized impacted populations (especially gay men), which eroded trust in health authorities. Groups like ACT UP protested government inaction.
Meeting of the AIDS Executive Committee (1987)Science History Institute
During the 1980s, AIDS researchers such as Dr. Anthony Fauci struggled to treat a virus that took years to cause symptoms and did not respond to existing drugs. They eventually learned to work with impacted communities to understand how to prevent infection instead.
Microbe Hunters continued to inspire physicians like Francisco Gonzalez-Crussi, who wrote in 1996 that “a new generation of microbe hunters will thwart the invaders once more.” By the mid-1990s, a cocktail of anti-viral medicines enabled people with AIDS to live for decades.
Microbe hunting in the age of COVID
The COVID-19 pandemic renewed readers’ interest in infectious disease. Between 2020 and 2023, at least 18 different publishers worldwide released new editions of Microbe Hunters. New covers echoed common media depictions of the coronavirus.
COVID Prevention and Treatment Supplies (2021/2025)Science History Institute
Modern-day microbe hunters swing into action
When the new disease emerged in December 2019, biomedical researchers identified the virus that causes COVID, developed detection methods, and within a year produced a vaccine that dramatically lowered death rates—though it could not prevent infection.
As director of the National Institutes for Allergy and Infectious Disease, Anthony Fauci became a key figure explaining the disease and public health responses to the American public. A 2021 public television documentary called Fauci “The Virus Hunter.”
COVID-19 Sign (2021/2023)Science History Institute
Some actions intended to protect public health became particularly controversial, including travel restrictions, school and business closures, vaccine mandates, and mask and social distancing recommendations.
Books on Anthony Fauci (2020/2024)Science History Institute
Public health becomes partisan
During the 2020s, American political parties divided over disease prevention. The stories circulating about public health officials, and Anthony Fauci in particular, became increasingly polarized. Cultivating opposition to biomedical science could be a winning political tactic.
Editions of "Microbe Hunters”Science History Institute
Conclusion
Despite early-20th century hopes that infectious diseases could be conquered, debates about how to best stop disease continue today. Stories about today’s microbe hunters circulate through books, TV, and social media. What kinds of stories do you think we should tell about them?
Written and curated by Alex Shehigian
Edited by Roger Turner, Judy Kaplan, and Jesse Smith
Digital design by Clare Hirai
Object photography by Jahna Auerbach
Image collage and map making by Alex Shehigian
