Polio

[Winter 2009]

Remembering the late HSPH Nobel Laureate, Thomas Weller

As the polio virus swept across the United States in 1948, 32-year-old Thomas Weller was logging long hours in a Harvard Medical School laboratory, working to develop a new way to culture viruses in test tubes so that scientists could then test drugs against the pathogens. Having already succeeded in growing the mumps virus, Weller now turned to his pet project: the chicken pox virus, varicella.

One day in March 1948, after adding varicella to several test tubes filled with human embryonic tissue and a special nutrient broth, Weller saw that four unused test tubes remained. It struck Weller and his collaborators, Drs. John Enders and Frederick Robbins, that the time was right for a new experiment.

From the freezer, Weller retrieved a sample of mouse brain infected with poliovirus and added it to the remaining test tubes, on the off chance that the virus might grow in the special broth. The varicella cultures never took, but, remarkably, the polio cultures did-an essential step in scientists’ quest to prevent the disease.

Until that point, researchers had only been able to grow poliovirus in its customary target, nervous tissue-with the result that experimental vaccines, made with weakened viruses, caused the immune systems of test animals to attack neurons in the brain, igniting dangerous levels of inflammation. By finding a way to grow the virus in non-nervous tissue, Weller helped make it possible for Albert Sabin and Jonas Salk to create safe polio vaccines.

SCIENCE FOR THE POOR
Weller later recalled no “eureka” moment. Persistence and serendipity had prevailed, and the breakthrough led to a Nobel Prize in physiology or medicine for Weller and his two colleagues in 1954. Their virus-culturing technique was soon widely adopted, making it possible to produce the vaccine on an industrial scale and immunize millions of people.

The Nobel came just months after Weller had joined the Harvard School of Public Health as the Richard Pearson Strong Professor of Public Health and head of the Department of Tropical Health (now Immunology and Infectious Diseases), a position from which he retired in 1981. He died on Aug. 23, 2008 at age 93.

In 1957, Weller isolated and cultured varicella as well as cytomegalovirus, a form of the herpes virus that can cause birth defects. In 1960, he accomplished the same feat for rubella, the cause of German measles, using virus obtained from his 10-year-old son, Robert. Later, focusing on parasitic diseases, Weller was involved in efforts to eradicate schistosomiasis in developing countries through the World Health Organization and other nongovernmental agencies.

Weller’s pioneering science ultimately helped save hundreds of millions of lives. Observes outgoing HSPH Dean Barry R. Bloom, an immunologist and vaccine expert: “Professor Weller became a champion for public health and the effort to focus the best of science on the diseases and problems of the poorest people on the globe.”

FROM BIRDS TO HUMANS
Weller initially appeared headed in a very different direction. He studied medical zoology and parasitology at the University of Michigan, where he published his first paper on tracking blue jays and did a master’s thesis on a fish parasite he had discovered. But at Harvard Medical School, Weller became interested in human parasitic and infectious diseases.

Weller’s clinical training in pediatrics got under way at Children’s Hospital in Boston but was interrupted by World War II. Enlisting in the Army Medical Corps, he was stationed in Puerto Rico, where he helped develop a malaria reporting system that led to reductions in the high infection rate at Fort Buchanan. By 1947, he was back at Children’s, where, with his former professor, John Enders, he co-founded the research division of infectious diseases.
In his autobiography, published in 2004, Growing Pathogens in Tissue Cultures: Fifty Years in Academic Tropical Medicine, Pediatrics, and Virology, Weller modestly chronicled his “life in science.”

“My primary goal was to pursue what I found interesting and medically important,” he wrote. “I was curious and tenacious, and I had my share of luck.”

MENTOR TO GREAT MINDS
Calling Weller “one of the greatest scientists of the 20th century,” Dyann Wirth, chair of the HSPH Department of Immunology and Infectious Diseases and the incumbent Richard Pearson Strong Professor of Infectious Diseases, told the Boston Globe that Weller had “a dedication to training the next generation, and a real vision of how to solve some of the biggest public health problems.”

Weller took great pride in mentoring young scientists. Among his many outstanding students at HSPH was William Foege. In the 1970s, this epidemiologist played a leading role in the successful campaign to eradicate smallpox worldwide.

A 2006 talk reprinted in Harvard Medical School’s alumni magazine captured Weller’s confidence in fresh, hungry talent. “I’d rather be recognized as an effective teacher than a Nobel laureate,” he said.

Amy Roeder is the Development Communications Coordinator in the Office for Resource Development at HSPH.
Photograph, Harvard Medical Library in the Francis A. Countway Library of Medicine