Dr. Julius S. Youngner, the last surviving member of the team that developed the Salk polio vaccine in the 1950s, died in his home on April 27 at the age of 96.
Dr. Youngner, like many scientists, pursued a passion to help people via his love of the scientific method. His own experiences as a child recovering from numerous infectious diseases, including severe pneumonia that almost killed him at age 7, inspired him to pursue a career in science — specifically, virology.
His interest in infectious disease led him to join Dr. Jonas Salk’s vaccine team at the University of Pittsburgh in the quest to fight polio. Polio crippled an average of 1,000 children every day in more than 125 countries during its peak. The polio vaccine ended this serious illness that plagued the United States from the late 1800s to the mid-20th century.
Dr. Youngner made three critical advances in the polio vaccine research, much of which relied on research with animals. He first devised a way to break down monkey cells so the team could grow large quantities of poliovirus in the lab. He then developed a way to inactivate the virus so it could be safely injected as a vaccine, and finally, he developed tests to determine the vaccine’s effectiveness in the first human patients. The number of polio cases went from an average of 35,000 a year before the vaccine to fewer than 2,500 two years later. Today, polio is virtually eradicated in the United States and much of the world.
Since his polio work, Dr. Youngner made other major advances in virology and immunology, continuing to rely on animal models. Youngner was the first to demonstrate that non-viral agents could trigger interferon infection in animals, and his research team devised a novel approach to antiviral therapy. By demonstrating that the live, attenuated virus vaccine for influenza A interacts with wild-type influenza to confer protection, rather than inducing a protective immune response, Youngner and his team demonstrated that this type of vaccine, tested in animal models, has the potential for significantly reducing morbidity and mortality associated with influenza.
A comprehensive obituary of Dr. Youngner, including his work on the Manhattan Project and his feud with Dr. Jonas Salk, was published on April 28 by the Pittsburgh Post-Gazette.