When Milton Winternitz came to Yale as chair of pathology in 1917, he brought with him a commitment to the U.S. Army to study the poison gases being used in the war. During the pandemic the Army Laboratory School at Yale, which studied human pathology, autopsied flu victims in New Haven.

In the United States the Spanish influenza pandemic of 1918 struck 28 percent of the population, killing 675,000 and depressing the average life span by 10 years. In Kansas, Camp Funston, built during World War I as a training camp, also served as an emergency hospital during the epidemic.

Studies of the pathology of the 1918 influenza pandemic in New Haven yielded three publications, and illustrations of diseased tissue by Armin Hemberger. His images appeared in Experimental Treatment and Pathology of Influenza, which counted Winternitz as one of its authors.

Yale’s Army Medical Laboratory and the 1918 Influenza Pandemic

Studies undertaken during World War I led to breakthroughs in chemotherapy, providing a new understanding of the pathology of the deadly influenza virus.

By Jennifer Kaylin

The two facilities established at Yale during World War I for training lab technicians for fieldwork and for studying the effects of poison gas were in existence for only three years, but during that brief period they created a legacy of teaching and patient care that is still relevant to students at the School of Medicine and to health practitioners around the world.

“In the early 20th century, Yale wasn’t a leader. There was no full-time faculty, and the teaching was mostly rote memorization followed by an apprenticeship,” said Michael Kashgarian, M.D. ’58, HS ’63, professor of pathology and molecular, cellular and developmental biology.

That changed in 1917, when Milton C. Winternitz, M.D., became chair of Yale ’s Department of Pathology. Winternitz brought with him the conviction that the study of medicine needed to be supported by science. He also brought a commitment to the U.S. Army that he would investigate the pathology of the poison gases that were being used in the Great War.

The Army set up the Medical Division of the Chemical Warfare Service at Yale and the Army Laboratory School at Yale, both to be overseen by Winternitz. The first facility focused on experimental animal pathology. Using dogs as experimental subjects, researchers counted red and white blood cells and examined the organs after the dogs were repeatedly exposed to poison gases. They described how these chemicals kill cells, and they made the significant observation that nitrogen mustard is particularly lethal to lymphoid tissues. Researchers at the second facility concentrated on human pathology, examining in autopsy the lungs of patients who had been exposed to mustard gas. Together, the two facilities provided the ideal setting for Winternitz to introduce his new scientifically based pedagogy.

In the midst of their work on gases used in war, researchers were hit with a new challenge: the influenza pandemic. In the autumn of 1918, this acute respiratory infection made its first appearance on the New England coast.

“Terrible as has been the war, the cost of life and distress … has been infinitesimal compared to the havoc caused by the late epidemic of influenza,” reads a passage from the New Haven Health Department’s 1918 annual report. From October through December of that year, the department recorded 777 deaths from influenza and its complications.

“People were healthy in the morning and dead by nightfall,” said Martin E. Gordon, M.D. ’46, clinical professor of medicine and chair of the board of trustees of the Cushing/Whitney Medical Library Associates.

The Army Laboratory School at Yale, located in the Brady Laboratory and one of several such schools around the country, was also set up to train laboratory technicians in bacteriology and pathology before dispatching them to medical field units. After the flu outbreak, the Laboratory School assumed the task of performing autopsies of the victims. They found that the pathology produced by influenza pneumonia closely resembled that produced by the inhalation of certain types of poison gas. Illustrators made a series of watercolors and drawings of the characteristic lesions. These pictures were part of an exhibit produced by Gordon called “The Flu and You: Old and New Threats” that appeared in conjunction with a lecture last spring by Harvey Fineberg, M.D., president of the Institute of Medicine of the National Academies of Science.

The work of both the poison gas and influenza researchers is also preserved in three monographs: The Pathology of War Gas Poisoning, Lethal War Gases—Physiology and Experimental Treatment and Pathology of Influenza. By the standards of the time, Kashgarian said, the biochemical and pathological observations presented in these volumes were state of the art, but even by today’s standards, they provide a “strong basis” for additional studies. “Given the tools they had, the information they present is very complete and thorough,” said Kashgarian.

One observation stands out—the researchers noticed that lymphatic and bone marrow tissue are destroyed by mustard gas. The therapeutic potential of this observation wasn’t explored until years later, but eventually researchers found that nitrogen mustard, derived from the family of chemicals used in battle, caused tumors in mice to shrink. Human trials were equally encouraging and paved the way for treating cancer with chemicals.

Jennifer Kaylin is a contributing editor of Yale Medicine and a freelance writer in New Haven.