In 1930 Eddy joined the
United States Public Health Service. In 1935 Eddy transferred to the
National Institutes of Health in
Bethesda, Maryland, where she joined the Biologics Control Division, the department responsible for checking the quality of
vaccines distributed by the
Federal government of the United States.
Flu vaccine testing During
World War II, Eddy was made responsible for checking the quality of
influenza vaccines used by the
United States Army. As part of the Biologics Control Division, Eddy and her team created the first reliable potency test for flu vaccines so that the quality and effectiveness would be consistent throughout manufacturing. Eddy tested Army flu vaccines for 16 years until she was promoted to chief of flu virus vaccine testing in 1944. In 1953, she was awarded the NIH Superior Accomplishment Award for the research on polio vaccines. After testing the vaccines on 18 monkeys, she and her team discovered that Cutter Laboratories' vaccine contained residual live
poliovirus, resulting in the monkeys showing polio-like symptoms and paralysis. Eddy found that three of the six batches paralyzed monkeys and therefore contained live polio virus. These findings pointed to a flawed vaccine manufacturing process at Cutter Laboratories. Eddy reported her findings regarding the flawed vaccines to the head of the Laboratory of Biologics Control, William Workman, who did not heed Eddy's warnings; the identified problems with the vaccine was not passed down to the licensing advisory committee. The exposures led to an
epidemic of polio in the families and communities of the affected children, resulting in the death of 5 children and 113 others paralyzed with the nastier paralytic poliomyelitis. On April 29, 1955
William Sebrell, the director of the National Institutes of Health, chaired a meeting to examine Cutter's manufacturing protocols. The meeting was also attended by Eddy and produced no conclusion on what Cutter should do differently in its manufacturing process.
Polyomavirus research After the
Cutter incident in 1954, Eddy had been sidelined for whistleblowing about the presence of live virus in Jonas Salk's inactivated polio vaccine. She was later on approached by
Sarah Elizabeth Stewart, her colleague at the National Institutes of Health, in 1956 while both were working on testing common cold vaccines. They did so by injecting the mice with ground organs of other mice that were known to contain leukemia, and observing cancerous tumor growth that was unrelated to leukemia. They satisfied
Koch's postulates to demonstrate that polyomavirus can cause
cancer to be transmitted from animal to animal. Stewart and Eddy continued to test the theory that viral components are able to induce tumors. They tested tumor extracts from both monkey and mouse embryos, and found that the mouse embryos contained a higher quantity of cancer causing viral agents, thus leading them to reason that viruses can be causative agents of cancer. They also concluded that the polyomavirus was able to cause 20 different types of mouse tumors. Eddy and Stewart demonstrated that the virus causes cell necrosis and proliferation in cell culture, that it is highly antigenic, and that it leads to formation of specific antibodies in infected animals whether or not tumors develop. At Eddy's suggestion, the virus was dubbed polyoma, which means many tumors. The virus was named the Stewart-Eddy or SE polyoma virus, after their respective surnames.
SV40 virus research In 1959, Eddy began to conduct safety studies on polio vaccines, which used viruses grown in monkey kidney cells. The extracts of these neoplasms were transplanted into a new group of mice where similar tumor growth was observed. Tumor extract transplants occurred for 5 generations of mice, where the last group all showed tumor growth. Eddy suggested that this contamination could be avoided in the future by screening cultures of
C. aethiops kidney cells for the characteristic cytopathic (cellular) changes that SV40 causes. Theoretically speaking, it added to a growing body of evidence that the monkey, like the mouse, could harbor oncogenic (cancer-causing) viruses that could affect other animal species. The question of whether SV40 causes cancer in humans remains controversial, however, and the development of improved assays for detection of SV40 in human tissues will be needed to resolve the controversy. == Other notable research ==