This article is part of Overlooked, a series of obituaries about remarkable people whose deaths, beginning in 1851, went unreported in The Times.
Yvonne Barr was a 31-year-old research assistant seeking a new challenge when she was hired by a pathologist in London in 1963 to help find the cause of an unusual malignancy: exceptionally large facial tumors in Ugandan children.
The pathologist, Anthony Epstein, was almost certain that the tumors were caused by a virus, but he was struggling to prove his hypothesis.
Barr was by then known for her superior laboratory skills, having worked on the bacterium that causes Hansen’s disease, commonly called leprosy, as well as other projects.
While she had mastered cell culture techniques — essentially promoting the growth of cells under controlled conditions — Epstein was having trouble sustaining the growth of cells in his lab.
“This was a key to the research — propagating cells that can continue to grow and become experimental specimens,” said Gregory J. Morgan, author of “Cancer Virus Hunters: A History of Tumor Virology” (2022). “Yvonne Barr had experience producing and caring for cell cultures before coming to Epstein’s lab in 1963, and perhaps this is why he hired her.”
Together, they would go on to make one of the 20th century’s most significant scientific discoveries: the first virus linked to causing cancer in humans, which came to be known as the Epstein-Barr virus.
Epstein’s death last month was noted by news outlets around the world. But when Barr died in 2016, few newspapers reported it, most likely because soon after the virus discovery, in 1964, she pivoted to a quiet career in teaching, which she pursued for decades.
Barr had first sought research positions in Australia, where she had moved with her husband, but was unable to land one.
“Her case illustrates the pervasive sexism of mid-20th century biomedicine,” said Morgan, an associate professor of the history and philosophy of science at the Stevens Institute of Technology in Hoboken, N.J. “She found science in Australia a bit of a boys club and could not obtain a permanent position.”
Yvonne Margaret Barr was born on March 11, 1932, in Carlow, Ireland, about an hour southwest of Dublin, the oldest of four children of Robert and Gertrude Barr. Her father was a banking manager.
She graduated from Banbridge Academy, in Northern Ireland, as head prefect, a position awarded to students designated as leaders and mentors. At Trinity College, in Dublin, she shined again, earning a degree in zoology and graduating with honors in 1953.
It was through jobs as research assistants from 1955 to 1962 that she gained her laboratory skills. At the London National Institute for Medical Research, she worked on the bacterium that causes leprosy and learned the cell propagation technique known as cell culture.
A second position, as a research assistant at the University of Toronto, allowed yet another opportunity to hone lab skills in experiments involving canine distemper virus, a pathogen that can cause a serious and often fatal infection in dogs as well as in other animals.
But as Barr was mastering cell culture techniques, Epstein, who worked at Middlesex Hospital Medical School in London, was struggling with them, Morgan said.
In 1963, Epstein received a $45,000 research grant from the U.S. National Institutes of Health and hired Barr and Bert Achong, an expert in electron microscopy. Both would complete doctorates while working in Epstein’s lab.
Epstein was already collaborating with Denis Burkitt, a surgeon and Presbyterian missionary in Uganda, who was sending tissue samples to London from biopsied facial tumors afflicting Ugandan children.
The cancer was known as Burkitt lymphoma, and because the tumors occurred in certain equatorial locations, Epstein strongly suspected a viral cause. What he needed was a more effective way to grow cells that possibly harbored the virus.
With Barr’s techniques, the team was able to sustain clusters of cells. Their research was the first to use cell culture techniques to study human B cells, the ones affected in Burkitt lymphoma, Morgan said.
In July 2022, The Irish Times quoted Barr as explaining why she thought Epstein’s early efforts weren’t working. “By the time I arrived at the Middlesex, I had a lot of tissue culture experience,” she wrote in an undated recollection. “I felt Epstein was throwing out the good cells. I applied my methods and every few days gave the cells a wash and new food.”
A tumor sample from Burkitt that initially seemed doomed after fog at Heathrow Airport delayed the delivery, turned out to be the one bearing definitive evidence of a causative virus.
“One day some of them were glistening, and that was thought to be a sign of life,” Barr, speaking from Australia, told a London conference by video in 2014. “There was great excitement, and the thing was to get enough for electron microscopy.”
From that cell cluster, Achong captured a crisp image, and Epstein immediately recognized the clear signature of a herpes virus that was new to science. The culprit was found. University of Pennsylvania researchers confirmed the results.
“The virus was named after the cell culture in which it was found,” Morgan explained. “The cell cultures were labeled EB1, for Epstein Barr 1, EB2, EB3, etc.”
Epstein-Barr virus, or E.B.V., is also the cause of mononucleosis and is strongly associated with Hodgkin’s lymphoma. An estimated 90 percent of the world’s adult population carries the virus.
Barr received a doctorate in 1966, a year after her marriage to Stuart Balding, an industrial chemist. After emigrating to Australia, they had two children, Kirsten and Sean Balding. She earned a diploma in education and became a high school math and science teacher. Her work in biomedical research had ended with the discovery in Epstein’s lab.
“She thought of the discovery as a small part of her life,” Kirsten Balding said in an interview. “I think she loved being a teacher and helping kids.”
Barr died on Feb. 13, 2016, in Melbourne after developing multiple medical problems, including diabetes and congestive heart failure, her daughter said. She was 83.